🚀 Feature: Add and apply more stricter golangci-lint linting rules (#2286)

* golangci-lint: add and apply more stricter linting rules

* github: drop security workflow now that we use gosec linter inside golangci-lint

* github: use official golangci-lint CI linter

* Add editorconfig and gitattributes file

.editorconfig

@@ -0,0 +1,8 @@
+; This file is for unifying the coding style for different editors and IDEs.
+; More information at http://editorconfig.org
+; This style originates from https://github.com/fewagency/best-practices
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf

.gitattributes

@@ -0,0 +1,12 @@
+# Handle line endings automatically for files detected as text
+# and leave all files detected as binary untouched.
+* text=auto eol=lf
+
+# Force batch scripts to always use CRLF line endings so that if a repo is accessed
+# in Windows via a file share from Linux, the scripts will work.
+*.{cmd,[cC][mM][dD]} text eol=crlf
+*.{bat,[bB][aA][tT]} text eol=crlf
+
+# Force bash scripts to always use LF line endings so that if a repo is accessed
+# in Unix via a file share from Windows, the scripts will work.
+*.sh text eol=lf

.github/workflows/linter.yml

@@ -1,17 +1,28 @@
+# Adapted from https://github.com/golangci/golangci-lint-action/blob/b56f6f529003f1c81d4d759be6bd5f10bf9a0fa0/README.md#how-to-use
+
+name: golangci-lint
 on:
-    push:
-        branches:
-            - master
-            - main
-    pull_request:
-name: Linter
+  push:
+    tags:
+      - v*
+    branches:
+      - master
+      - main
+  pull_request:
+permissions:
+  contents: read
 jobs:
-  Golint:
+  golangci:
+    name: lint
     runs-on: ubuntu-latest
     steps:
-      - name: Fetch Repository
-        uses: actions/checkout@v3
-      - name: Run Golint
-        uses: reviewdog/action-golangci-lint@v2
+      - uses: actions/setup-go@v3
         with:
-          golangci_lint_flags: "--tests=false"
+          # NOTE: Keep this in sync with the version from go.mod
+          go-version: 1.19
+      - uses: actions/checkout@v3
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3
+        with:
+          # NOTE: Keep this in sync with the version from .golangci.yml
+          version: v1.50.1

.github/workflows/security.yml

@@ -1,17 +0,0 @@
-on:
-    push:
-        branches:
-            - master
-            - main
-    pull_request:
-name: Security
-jobs:
-  Gosec:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Fetch Repository
-        uses: actions/checkout@v3
-      - name: Run Gosec
-        uses: securego/gosec@master
-        with:
-          args: -exclude-dir=internal/*/ ./...

.golangci.yml

@@ -0,0 +1,258 @@
+# Created based on v1.50.1
+# NOTE: Keep this in sync with the version in .github/workflows/linter.yml
+
+run:
+  modules-download-mode: readonly
+  skip-dirs-use-default: false
+  skip-dirs:
+    - internal # TODO: Also apply proper linting for internal dir
+
+output:
+  sort-results: true
+
+linters-settings:
+  # TODO: Eventually enable these checks
+  # depguard:
+  #   include-go-root: true
+  #   packages:
+  #     - flag
+  #     - io/ioutil
+  #     - reflect
+  #     - unsafe
+  #   packages-with-error-message:
+  #     - flag: '`flag` package is only allowed in main.go'
+  #     - io/ioutil: '`io/ioutil` package is deprecated, use the `io` and `os` package instead'
+  #     - reflect: '`reflect` package is dangerous to use'
+  #     - unsafe: '`unsafe` package is dangerous to use'
+
+  errcheck:
+     check-type-assertions: true
+     check-blank: true
+     disable-default-exclusions: true
+
+  errchkjson:
+    report-no-exported: true
+
+  exhaustive:
+    default-signifies-exhaustive: true
+
+  forbidigo:
+    forbid:
+      - ^(fmt\.Print(|f|ln)|print|println)$
+      - 'http\.Default(Client|Transport)'
+      # TODO: Eventually enable these patterns
+      # - 'time\.Sleep'
+      # - 'panic'
+
+  gci:
+    sections:
+      - standard
+      - prefix(github.com/gofiber/fiber)
+      - default
+      - blank
+      - dot
+    custom-order: true
+
+  gocritic:
+    disabled-checks:
+      - ifElseChain
+
+  gofumpt:
+    module-path: github.com/gofiber/fiber
+    extra-rules: true
+
+  gosec:
+    config:
+      global:
+        audit: true
+
+  govet:
+    check-shadowing: true
+    enable-all: true
+    disable:
+      - shadow
+      - fieldalignment
+
+  grouper:
+    import-require-single-import: true
+    import-require-grouping: true
+
+  misspell:
+    locale: US
+
+  nolintlint:
+    require-explanation: true
+    require-specific: true
+
+  nonamedreturns:
+    report-error-in-defer: true
+
+  predeclared:
+    q: true
+
+  promlinter:
+    strict: true
+
+  revive:
+    enable-all-rules: true
+    rules:
+      # Provided by gomnd linter
+      - name: add-constant
+        disabled: true
+      - name: argument-limit
+        disabled: true
+      # Provided by bidichk
+      - name: banned-characters
+        disabled: true
+      - name: cognitive-complexity
+        disabled: true
+      - name: cyclomatic
+        disabled: true
+      - name: exported
+        disabled: true
+      - name: file-header
+        disabled: true
+      - name: function-result-limit
+        disabled: true
+      - name: function-length
+        disabled: true
+      - name: line-length-limit
+        disabled: true
+      - name: max-public-structs
+        disabled: true
+      - name: modifies-parameter
+        disabled: true
+      - name: nested-structs
+        disabled: true
+      - name: package-comments
+        disabled: true
+
+  stylecheck:
+    checks:
+      - all
+      - -ST1000
+      - -ST1020
+      - -ST1021
+      - -ST1022
+
+  tagliatelle:
+    case:
+      rules:
+        json: snake
+
+  #tenv:
+  #  all: true
+
+  #unparam:
+  #  check-exported: true
+
+  wrapcheck:
+    ignorePackageGlobs:
+      - github.com/gofiber/fiber/*
+      - github.com/valyala/fasthttp
+
+issues:
+   exclude-use-default: false
+
+linters:
+  enable:
+    - asasalint
+    - asciicheck
+    - bidichk
+    - bodyclose
+    - containedctx
+    - contextcheck
+    # - cyclop
+    # - deadcode
+    # - decorder
+    - depguard
+    - dogsled
+    # - dupl
+    # - dupword
+    - durationcheck
+    - errcheck
+    - errchkjson
+    - errname
+    - errorlint
+    - execinquery
+    - exhaustive
+    # - exhaustivestruct
+    # - exhaustruct
+    - exportloopref
+    - forbidigo
+    - forcetypeassert
+    # - funlen
+    - gci
+    - gochecknoglobals
+    - gochecknoinits
+    # - gocognit
+    - goconst
+    - gocritic
+    # - gocyclo
+    # - godot
+    # - godox
+    # - goerr113
+    - gofmt
+    - gofumpt
+    # - goheader
+    - goimports
+    # - golint
+    - gomnd
+    - gomoddirectives
+    # - gomodguard
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - grouper
+    # - ifshort
+    # - importas
+    - ineffassign
+    # - interfacebloat
+    # - interfacer
+    # - ireturn
+    # - lll
+    - loggercheck
+    # - maintidx
+    # - makezero
+    # - maligned
+    - misspell
+    - nakedret
+    # - nestif
+    - nilerr
+    - nilnil
+    # - nlreturn
+    - noctx
+    - nolintlint
+    - nonamedreturns
+    # - nosnakecase
+    - nosprintfhostport
+    # - paralleltest # TODO: Enable once https://github.com/gofiber/fiber/issues/2254 is implemented
+    # - prealloc
+    - predeclared
+    - promlinter
+    - reassign
+    - revive
+    - rowserrcheck
+    # - scopelint
+    - sqlclosecheck
+    - staticcheck
+    # - structcheck
+    - stylecheck
+    - tagliatelle
+    # - tenv # TODO: Enable once we drop support for Go 1.16
+    # - testableexamples
+    # - testpackage # TODO: Enable once https://github.com/gofiber/fiber/issues/2252 is implemented
+    - thelper
+    # - tparallel # TODO: Enable once https://github.com/gofiber/fiber/issues/2254 is implemented
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    - usestdlibvars
+    # - varcheck
+    # - varnamelen
+    - wastedassign
+    - whitespace
+    - wrapcheck
+    # - wsl

app.go

@@ -14,6 +14,7 @@ import (
 	"encoding/xml"
 	"errors"
 	"fmt"
+	"log"
 	"net"
 	"net/http"
 	"net/http/httputil"
@@ -24,6 +25,7 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -306,7 +308,7 @@ type Config struct {
 
 	// FEATURE: v2.3.x
 	// The router executes the same handler by default if StrictRouting or CaseSensitive is disabled.
-	// Enabling RedirectFixedPath will change this behaviour into a client redirect to the original route path.
+	// Enabling RedirectFixedPath will change this behavior into a client redirect to the original route path.
 	// Using the status code 301 for GET requests and 308 for all other request methods.
 	//
 	// Default: false
@@ -454,6 +456,8 @@ const (
 )
 
 // HTTP methods enabled by default
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var DefaultMethods = []string{
 	MethodGet,
 	MethodHead,
@@ -467,7 +471,7 @@ var DefaultMethods = []string{
 }
 
 // DefaultErrorHandler that process return errors from handlers
-var DefaultErrorHandler = func(c *Ctx, err error) error {
+func DefaultErrorHandler(c *Ctx, err error) error {
 	code := StatusInternalServerError
 	var e *Error
 	if errors.As(err, &e) {
@@ -519,7 +523,7 @@ func New(config ...Config) *App {
 
 	if app.config.ETag {
 		if !IsChild() {
-			fmt.Println("[Warning] Config.ETag is deprecated since v2.0.6, please use 'middleware/etag'.")
+			log.Printf("[Warning] Config.ETag is deprecated since v2.0.6, please use 'middleware/etag'.\n")
 		}
 	}
 
@@ -587,7 +591,7 @@ func (app *App) handleTrustedProxy(ipAddress string) {
 	if strings.Contains(ipAddress, "/") {
 		_, ipNet, err := net.ParseCIDR(ipAddress)
 		if err != nil {
-			fmt.Printf("[Warning] IP range %q could not be parsed: %v\n", ipAddress, err)
+			log.Printf("[Warning] IP range %q could not be parsed: %v\n", ipAddress, err)
 		} else {
 			app.config.trustedProxyRanges = append(app.config.trustedProxyRanges, ipNet)
 		}
@@ -822,7 +826,7 @@ func (app *App) Config() Config {
 }
 
 // Handler returns the server handler.
-func (app *App) Handler() fasthttp.RequestHandler {
+func (app *App) Handler() fasthttp.RequestHandler { //revive:disable-line:confusing-naming // Having both a Handler() (uppercase) and a handler() (lowercase) is fine. TODO: Use nolint:revive directive instead. See https://github.com/golangci/golangci-lint/issues/3476
 	// prepare the server for the start
 	app.startupProcess()
 	return app.handler
@@ -887,7 +891,7 @@ func (app *App) Hooks() *Hooks {
 
 // Test is used for internal debugging by passing a *http.Request.
 // Timeout is optional and defaults to 1s, -1 will disable it completely.
-func (app *App) Test(req *http.Request, msTimeout ...int) (resp *http.Response, err error) {
+func (app *App) Test(req *http.Request, msTimeout ...int) (*http.Response, error) {
 	// Set timeout
 	timeout := 1000
 	if len(msTimeout) > 0 {
@@ -902,15 +906,15 @@ func (app *App) Test(req *http.Request, msTimeout ...int) (resp *http.Response,
 	// Dump raw http request
 	dump, err := httputil.DumpRequest(req, true)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("failed to dump request: %w", err)
 	}
 
 	// Create test connection
 	conn := new(testConn)
 
 	// Write raw http request
-	if _, err = conn.r.Write(dump); err != nil {
-		return nil, err
+	if _, err := conn.r.Write(dump); err != nil {
+		return nil, fmt.Errorf("failed to write: %w", err)
 	}
 	// prepare the server for the start
 	app.startupProcess()
@@ -943,7 +947,7 @@ func (app *App) Test(req *http.Request, msTimeout ...int) (resp *http.Response,
 	}
 
 	// Check for errors
-	if err != nil && err != fasthttp.ErrGetOnly {
+	if err != nil && !errors.Is(err, fasthttp.ErrGetOnly) {
 		return nil, err
 	}
 
@@ -951,12 +955,17 @@ func (app *App) Test(req *http.Request, msTimeout ...int) (resp *http.Response,
 	buffer := bufio.NewReader(&conn.w)
 
 	// Convert raw http response to *http.Response
-	return http.ReadResponse(buffer, req)
+	res, err := http.ReadResponse(buffer, req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response: %w", err)
+	}
+
+	return res, nil
 }
 
 type disableLogger struct{}
 
-func (dl *disableLogger) Printf(_ string, _ ...interface{}) {
+func (*disableLogger) Printf(_ string, _ ...interface{}) {
 	// fmt.Println(fmt.Sprintf(format, args...))
 }
 
@@ -967,7 +976,7 @@ func (app *App) init() *App {
 	// Only load templates if a view engine is specified
 	if app.config.Views != nil {
 		if err := app.config.Views.Load(); err != nil {
-			fmt.Printf("views: %v\n", err)
+			log.Printf("[Warning]: failed to load views: %v\n", err)
 		}
 	}
 
@@ -1039,25 +1048,30 @@ func (app *App) ErrorHandler(ctx *Ctx, err error) error {
 // errors before calling the application's error handler method.
 func (app *App) serverErrorHandler(fctx *fasthttp.RequestCtx, err error) {
 	c := app.AcquireCtx(fctx)
-	if _, ok := err.(*fasthttp.ErrSmallBuffer); ok {
+	defer app.ReleaseCtx(c)
+
+	var errNetOP *net.OpError
+
+	switch {
+	case errors.As(err, new(*fasthttp.ErrSmallBuffer)):
 		err = ErrRequestHeaderFieldsTooLarge
-	} else if netErr, ok := err.(*net.OpError); ok && netErr.Timeout() {
+	case errors.As(err, &errNetOP) && errNetOP.Timeout():
 		err = ErrRequestTimeout
-	} else if err == fasthttp.ErrBodyTooLarge {
+	case errors.Is(err, fasthttp.ErrBodyTooLarge):
 		err = ErrRequestEntityTooLarge
-	} else if err == fasthttp.ErrGetOnly {
+	case errors.Is(err, fasthttp.ErrGetOnly):
 		err = ErrMethodNotAllowed
-	} else if strings.Contains(err.Error(), "timeout") {
+	case strings.Contains(err.Error(), "timeout"):
 		err = ErrRequestTimeout
-	} else {
+	default:
 		err = NewError(StatusBadRequest, err.Error())
 	}
 
 	if catch := app.ErrorHandler(c, err); catch != nil {
-		_ = c.SendStatus(StatusInternalServerError)
+		log.Printf("serverErrorHandler: failed to call ErrorHandler: %v\n", catch)
+		_ = c.SendStatus(StatusInternalServerError) //nolint:errcheck // It is fine to ignore the error here
+		return
 	}
-
-	app.ReleaseCtx(c)
 }
 
 // startupProcess Is the method which executes all the necessary processes just before the start of the server.

app_test.go

@@ -2,6 +2,7 @@
 // 🤖 Github Repository: https://github.com/gofiber/fiber
 // 📌 API Documentation: https://docs.gofiber.io
 
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package fiber
 
 import (
@@ -23,15 +24,16 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 	"github.com/valyala/fasthttp/fasthttputil"
 )
 
-var testEmptyHandler = func(c *Ctx) error {
+func testEmptyHandler(_ *Ctx) error {
 	return nil
 }
 
-func testStatus200(t *testing.T, app *App, url string, method string) {
+func testStatus200(t *testing.T, app *App, url, method string) {
 	t.Helper()
 
 	req := httptest.NewRequest(method, url, nil)
@@ -42,6 +44,8 @@ func testStatus200(t *testing.T, app *App, url string, method string) {
 }
 
 func testErrorResponse(t *testing.T, err error, resp *http.Response, expectedBodyError string) {
+	t.Helper()
+
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, 500, resp.StatusCode, "Status code")
 
@@ -140,7 +144,6 @@ func Test_App_ServerErrorHandler_SmallReadBuffer(t *testing.T) {
 	logHeaderSlice := make([]string, 5000)
 	request.Header.Set("Very-Long-Header", strings.Join(logHeaderSlice, "-"))
 	_, err := app.Test(request)
-
 	if err == nil {
 		t.Error("Expect an error at app.Test(request)")
 	}
@@ -470,7 +473,6 @@ func Test_App_Use_MultiplePrefix(t *testing.T) {
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "/test/doe", string(body))
-
 }
 
 func Test_App_Use_StrictRouting(t *testing.T) {
@@ -515,7 +517,7 @@ func Test_App_Add_Method_Test(t *testing.T) {
 		}
 	}()
 
-	methods := append(DefaultMethods, "JOHN")
+	methods := append(DefaultMethods, "JOHN") //nolint:gocritic // We want a new slice here
 	app := New(Config{
 		RequestMethods: methods,
 	})
@@ -780,7 +782,7 @@ func Test_App_ShutdownWithTimeout(t *testing.T) {
 	case <-timer.C:
 		t.Fatal("idle connections not closed on shutdown")
 	case err := <-shutdownErr:
-		if err == nil || err != context.DeadlineExceeded {
+		if err == nil || !errors.Is(err, context.DeadlineExceeded) {
 			t.Fatalf("unexpected err %v. Expecting %v", err, context.DeadlineExceeded)
 		}
 	}
@@ -852,7 +854,7 @@ func Test_App_Static_MaxAge(t *testing.T) {
 
 	app.Static("/", "./.github", Static{MaxAge: 100})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/index.html", nil))
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/index.html", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, 200, resp.StatusCode, "Status code")
 	utils.AssertEqual(t, false, resp.Header.Get(HeaderContentLength) == "")
@@ -866,19 +868,19 @@ func Test_App_Static_Custom_CacheControl(t *testing.T) {
 	app := New()
 
 	app.Static("/", "./.github", Static{ModifyResponse: func(c *Ctx) error {
-		if strings.Contains(string(c.GetRespHeader("Content-Type")), "text/html") {
+		if strings.Contains(c.GetRespHeader("Content-Type"), "text/html") {
 			c.Response().Header.Set("Cache-Control", "no-cache, no-store, must-revalidate")
 		}
 		return nil
 	}})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/index.html", nil))
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/index.html", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, "no-cache, no-store, must-revalidate", resp.Header.Get(HeaderCacheControl), "CacheControl Control")
 
-	normal_resp, normal_err := app.Test(httptest.NewRequest("GET", "/config.yml", nil))
-	utils.AssertEqual(t, nil, normal_err, "app.Test(req)")
-	utils.AssertEqual(t, "", normal_resp.Header.Get(HeaderCacheControl), "CacheControl Control")
+	respNormal, errNormal := app.Test(httptest.NewRequest(MethodGet, "/config.yml", nil))
+	utils.AssertEqual(t, nil, errNormal, "app.Test(req)")
+	utils.AssertEqual(t, "", respNormal.Header.Get(HeaderCacheControl), "CacheControl Control")
 }
 
 // go test -run Test_App_Static_Download
@@ -890,7 +892,7 @@ func Test_App_Static_Download(t *testing.T) {
 
 	app.Static("/fiber.png", "./.github/testdata/fs/img/fiber.png", Static{Download: true})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/fiber.png", nil))
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/fiber.png", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, 200, resp.StatusCode, "Status code")
 	utils.AssertEqual(t, false, resp.Header.Get(HeaderContentLength) == "")
@@ -1067,7 +1069,7 @@ func Test_App_Static_Next(t *testing.T) {
 
 	t.Run("app.Static is skipped: invoking Get handler", func(t *testing.T) {
 		t.Parallel()
-		req := httptest.NewRequest("GET", "/", nil)
+		req := httptest.NewRequest(MethodGet, "/", nil)
 		req.Header.Set("X-Custom-Header", "skip")
 		resp, err := app.Test(req)
 		utils.AssertEqual(t, nil, err)
@@ -1082,7 +1084,7 @@ func Test_App_Static_Next(t *testing.T) {
 
 	t.Run("app.Static is not skipped: serving index.html", func(t *testing.T) {
 		t.Parallel()
-		req := httptest.NewRequest("GET", "/", nil)
+		req := httptest.NewRequest(MethodGet, "/", nil)
 		req.Header.Set("X-Custom-Header", "don't skip")
 		resp, err := app.Test(req)
 		utils.AssertEqual(t, nil, err)
@@ -1379,7 +1381,7 @@ func Test_Test_DumpError(t *testing.T) {
 
 	resp, err := app.Test(httptest.NewRequest(MethodGet, "/", errorReader(0)))
 	utils.AssertEqual(t, true, resp == nil)
-	utils.AssertEqual(t, "errorReader", err.Error())
+	utils.AssertEqual(t, "failed to dump request: errorReader", err.Error())
 }
 
 // go test -run Test_App_Handler
@@ -1393,7 +1395,7 @@ type invalidView struct{}
 
 func (invalidView) Load() error { return errors.New("invalid view") }
 
-func (i invalidView) Render(io.Writer, string, interface{}, ...string) error { panic("implement me") }
+func (invalidView) Render(io.Writer, string, interface{}, ...string) error { panic("implement me") }
 
 // go test -run Test_App_Init_Error_View
 func Test_App_Init_Error_View(t *testing.T) {
@@ -1405,7 +1407,9 @@ func Test_App_Init_Error_View(t *testing.T) {
 			utils.AssertEqual(t, "implement me", fmt.Sprintf("%v", err))
 		}
 	}()
-	_ = app.config.Views.Render(nil, "", nil)
+
+	err := app.config.Views.Render(nil, "", nil)
+	utils.AssertEqual(t, nil, err)
 }
 
 // go test -run Test_App_Stack
@@ -1535,11 +1539,12 @@ func Test_App_SmallReadBuffer(t *testing.T) {
 
 	go func() {
 		time.Sleep(500 * time.Millisecond)
-		resp, err := http.Get("http://127.0.0.1:4006/small-read-buffer")
-		if resp != nil {
-			utils.AssertEqual(t, 431, resp.StatusCode)
-		}
+		req, err := http.NewRequestWithContext(context.Background(), MethodGet, "http://127.0.0.1:4006/small-read-buffer", http.NoBody)
 		utils.AssertEqual(t, nil, err)
+		var client http.Client
+		resp, err := client.Do(req)
+		utils.AssertEqual(t, nil, err)
+		utils.AssertEqual(t, 431, resp.StatusCode)
 		utils.AssertEqual(t, nil, app.Shutdown())
 	}()
 
@@ -1572,13 +1577,13 @@ func Test_App_New_Test_Parallel(t *testing.T) {
 	t.Run("Test_App_New_Test_Parallel_1", func(t *testing.T) {
 		t.Parallel()
 		app := New(Config{Immutable: true})
-		_, err := app.Test(httptest.NewRequest("GET", "/", nil))
+		_, err := app.Test(httptest.NewRequest(MethodGet, "/", nil))
 		utils.AssertEqual(t, nil, err)
 	})
 	t.Run("Test_App_New_Test_Parallel_2", func(t *testing.T) {
 		t.Parallel()
 		app := New(Config{Immutable: true})
-		_, err := app.Test(httptest.NewRequest("GET", "/", nil))
+		_, err := app.Test(httptest.NewRequest(MethodGet, "/", nil))
 		utils.AssertEqual(t, nil, err)
 	})
 }
@@ -1591,7 +1596,7 @@ func Test_App_ReadBodyStream(t *testing.T) {
 		return c.SendString(fmt.Sprintf("%v %s", c.Request().IsBodyStream(), c.Body()))
 	})
 	testString := "this is a test"
-	resp, err := app.Test(httptest.NewRequest("POST", "/", bytes.NewBufferString(testString)))
+	resp, err := app.Test(httptest.NewRequest(MethodPost, "/", bytes.NewBufferString(testString)))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err, "io.ReadAll(resp.Body)")
@@ -1615,12 +1620,12 @@ func Test_App_DisablePreParseMultipartForm(t *testing.T) {
 		}
 		file, err := mpf.File["test"][0].Open()
 		if err != nil {
-			return err
+			return fmt.Errorf("failed to open: %w", err)
 		}
 		buffer := make([]byte, len(testString))
 		n, err := file.Read(buffer)
 		if err != nil {
-			return err
+			return fmt.Errorf("failed to read: %w", err)
 		}
 		if n != len(testString) {
 			return fmt.Errorf("bad read length")
@@ -1636,7 +1641,7 @@ func Test_App_DisablePreParseMultipartForm(t *testing.T) {
 	utils.AssertEqual(t, len(testString), n, "writer n")
 	utils.AssertEqual(t, nil, w.Close(), "w.Close()")
 
-	req := httptest.NewRequest("POST", "/", b)
+	req := httptest.NewRequest(MethodPost, "/", b)
 	req.Header.Set("Content-Type", w.FormDataContentType())
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
@@ -1659,7 +1664,7 @@ func Test_App_Test_no_timeout_infinitely(t *testing.T) {
 			return nil
 		})
 
-		req := httptest.NewRequest(http.MethodGet, "/", http.NoBody)
+		req := httptest.NewRequest(MethodGet, "/", http.NoBody)
 		_, err = app.Test(req, -1)
 	}()
 
@@ -1696,7 +1701,7 @@ func Test_App_SetTLSHandler(t *testing.T) {
 
 func Test_App_AddCustomRequestMethod(t *testing.T) {
 	t.Parallel()
-	methods := append(DefaultMethods, "TEST")
+	methods := append(DefaultMethods, "TEST") //nolint:gocritic // We want a new slice here
 	app := New(Config{
 		RequestMethods: methods,
 	})

client.go

@@ -15,6 +15,7 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -50,6 +51,7 @@ type Args = fasthttp.Args
 // Copy from fasthttp
 type RetryIfFunc = fasthttp.RetryIfFunc
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var defaultClient Client
 
 // Client implements http client.
@@ -186,11 +188,11 @@ func (a *Agent) Parse() error {
 
 	uri := a.req.URI()
 
-	isTLS := false
+	var isTLS bool
 	scheme := uri.Scheme()
-	if bytes.Equal(scheme, strHTTPS) {
+	if bytes.Equal(scheme, []byte(schemeHTTPS)) {
 		isTLS = true
-	} else if !bytes.Equal(scheme, strHTTP) {
+	} else if !bytes.Equal(scheme, []byte(schemeHTTP)) {
 		return fmt.Errorf("unsupported protocol %q. http and https are supported", scheme)
 	}
 
@@ -241,7 +243,7 @@ func (a *Agent) SetBytesV(k string, v []byte) *Agent {
 // SetBytesKV sets the given 'key: value' header.
 //
 // Use AddBytesKV for setting multiple header values under the same key.
-func (a *Agent) SetBytesKV(k []byte, v []byte) *Agent {
+func (a *Agent) SetBytesKV(k, v []byte) *Agent {
 	a.req.Header.SetBytesKV(k, v)
 
 	return a
@@ -281,7 +283,7 @@ func (a *Agent) AddBytesV(k string, v []byte) *Agent {
 //
 // Multiple headers with the same key may be added with this function.
 // Use SetBytesKV for setting a single header for the given key.
-func (a *Agent) AddBytesKV(k []byte, v []byte) *Agent {
+func (a *Agent) AddBytesKV(k, v []byte) *Agent {
 	a.req.Header.AddBytesKV(k, v)
 
 	return a
@@ -652,10 +654,8 @@ func (a *Agent) Reuse() *Agent {
 // certificate chain and host name.
 func (a *Agent) InsecureSkipVerify() *Agent {
 	if a.HostClient.TLSConfig == nil {
-		/* #nosec G402 */
-		a.HostClient.TLSConfig = &tls.Config{InsecureSkipVerify: true} // #nosec G402
+		a.HostClient.TLSConfig = &tls.Config{InsecureSkipVerify: true} //nolint:gosec // We explicitly let the user set insecure mode here
 	} else {
-		/* #nosec G402 */
 		a.HostClient.TLSConfig.InsecureSkipVerify = true
 	}
 
@@ -728,14 +728,14 @@ func (a *Agent) RetryIf(retryIf RetryIfFunc) *Agent {
 // Bytes returns the status code, bytes body and errors of url.
 //
 // it's not safe to use Agent after calling [Agent.Bytes]
-func (a *Agent) Bytes() (code int, body []byte, errs []error) {
+func (a *Agent) Bytes() (int, []byte, []error) {
 	defer a.release()
 	return a.bytes()
 }
 
-func (a *Agent) bytes() (code int, body []byte, errs []error) {
+func (a *Agent) bytes() (code int, body []byte, errs []error) { //nolint:nonamedreturns,revive // We want to overwrite the body in a deferred func. TODO: Check if we really need to do this. We eventually want to get rid of all named returns.
 	if errs = append(errs, a.errs...); len(errs) > 0 {
-		return
+		return code, body, errs
 	}
 
 	var (
@@ -760,7 +760,7 @@ func (a *Agent) bytes() (code int, body []byte, errs []error) {
 			code = resp.StatusCode()
 		}
 
-		body = append(a.dest, resp.Body()...)
+		body = append(a.dest, resp.Body()...) //nolint:gocritic // We want to append to the returned slice here
 
 		if nilResp {
 			ReleaseResponse(resp)
@@ -770,25 +770,25 @@ func (a *Agent) bytes() (code int, body []byte, errs []error) {
 	if a.timeout > 0 {
 		if err := a.HostClient.DoTimeout(req, resp, a.timeout); err != nil {
 			errs = append(errs, err)
-			return
+			return code, body, errs
 		}
 	} else if a.maxRedirectsCount > 0 && (string(req.Header.Method()) == MethodGet || string(req.Header.Method()) == MethodHead) {
 		if err := a.HostClient.DoRedirects(req, resp, a.maxRedirectsCount); err != nil {
 			errs = append(errs, err)
-			return
+			return code, body, errs
 		}
 	} else if err := a.HostClient.Do(req, resp); err != nil {
 		errs = append(errs, err)
 	}
 
-	return
+	return code, body, errs
 }
 
 func printDebugInfo(req *Request, resp *Response, w io.Writer) {
 	msg := fmt.Sprintf("Connected to %s(%s)\r\n\r\n", req.URI().Host(), resp.RemoteAddr())
-	_, _ = w.Write(utils.UnsafeBytes(msg))
-	_, _ = req.WriteTo(w)
-	_, _ = resp.WriteTo(w)
+	_, _ = w.Write(utils.UnsafeBytes(msg)) //nolint:errcheck // This will never fail
+	_, _ = req.WriteTo(w)                  //nolint:errcheck // This will never fail
+	_, _ = resp.WriteTo(w)                 //nolint:errcheck // This will never fail
 }
 
 // String returns the status code, string body and errors of url.
@@ -797,6 +797,7 @@ func printDebugInfo(req *Request, resp *Response, w io.Writer) {
 func (a *Agent) String() (int, string, []error) {
 	defer a.release()
 	code, body, errs := a.bytes()
+	// TODO: There might be a data race here on body. Maybe use utils.CopyBytes on it?
 
 	return code, utils.UnsafeString(body), errs
 }
@@ -805,12 +806,15 @@ func (a *Agent) String() (int, string, []error) {
 // And bytes body will be unmarshalled to given v.
 //
 // it's not safe to use Agent after calling [Agent.Struct]
-func (a *Agent) Struct(v interface{}) (code int, body []byte, errs []error) {
+func (a *Agent) Struct(v interface{}) (int, []byte, []error) {
 	defer a.release()
-	if code, body, errs = a.bytes(); len(errs) > 0 {
-		return
+
+	code, body, errs := a.bytes()
+	if len(errs) > 0 {
+		return code, body, errs
 	}
 
+	// TODO: This should only be done once
 	if a.jsonDecoder == nil {
 		a.jsonDecoder = json.Unmarshal
 	}
@@ -819,7 +823,7 @@ func (a *Agent) Struct(v interface{}) (code int, body []byte, errs []error) {
 		errs = append(errs, err)
 	}
 
-	return
+	return code, body, errs
 }
 
 func (a *Agent) release() {
@@ -855,6 +859,7 @@ func (a *Agent) reset() {
 	a.formFiles = a.formFiles[:0]
 }
 
+//nolint:gochecknoglobals // TODO: Do not use global vars here
 var (
 	clientPool sync.Pool
 	agentPool  = sync.Pool{
@@ -877,7 +882,11 @@ func AcquireClient() *Client {
 	if v == nil {
 		return &Client{}
 	}
-	return v.(*Client)
+	c, ok := v.(*Client)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *Client"))
+	}
+	return c
 }
 
 // ReleaseClient returns c acquired via AcquireClient to client pool.
@@ -899,7 +908,11 @@ func ReleaseClient(c *Client) {
 // no longer needed. This allows Agent recycling, reduces GC pressure
 // and usually improves performance.
 func AcquireAgent() *Agent {
-	return agentPool.Get().(*Agent)
+	a, ok := agentPool.Get().(*Agent)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *Agent"))
+	}
+	return a
 }
 
 // ReleaseAgent returns a acquired via AcquireAgent to Agent pool.
@@ -922,7 +935,11 @@ func AcquireResponse() *Response {
 	if v == nil {
 		return &Response{}
 	}
-	return v.(*Response)
+	r, ok := v.(*Response)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *Response"))
+	}
+	return r
 }
 
 // ReleaseResponse return resp acquired via AcquireResponse to response pool.
@@ -945,7 +962,11 @@ func AcquireArgs() *Args {
 	if v == nil {
 		return &Args{}
 	}
-	return v.(*Args)
+	a, ok := v.(*Args)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *Args"))
+	}
+	return a
 }
 
 // ReleaseArgs returns the object acquired via AcquireArgs to the pool.
@@ -966,7 +987,11 @@ func AcquireFormFile() *FormFile {
 	if v == nil {
 		return &FormFile{}
 	}
-	return v.(*FormFile)
+	ff, ok := v.(*FormFile)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *FormFile"))
+	}
+	return ff
 }
 
 // ReleaseFormFile returns the object acquired via AcquireFormFile to the pool.
@@ -981,9 +1006,7 @@ func ReleaseFormFile(ff *FormFile) {
 	formFilePool.Put(ff)
 }
 
-var (
-	strHTTP          = []byte("http")
-	strHTTPS         = []byte("https")
+const (
 	defaultUserAgent = "fiber"
 )
 

client_test.go

@@ -1,3 +1,4 @@
+//nolint:wrapcheck // We must not wrap errors in tests
 package fiber
 
 import (
@@ -19,6 +20,7 @@ import (
 
 	"github.com/gofiber/fiber/v2/internal/tlstest"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp/fasthttputil"
 )
 
@@ -295,8 +297,10 @@ func Test_Client_Agent_Set_Or_Add_Headers(t *testing.T) {
 	handler := func(c *Ctx) error {
 		c.Request().Header.VisitAll(func(key, value []byte) {
 			if k := string(key); k == "K1" || k == "K2" {
-				_, _ = c.Write(key)
-				_, _ = c.Write(value)
+				_, err := c.Write(key)
+				utils.AssertEqual(t, nil, err)
+				_, err = c.Write(value)
+				utils.AssertEqual(t, nil, err)
 			}
 		})
 		return nil
@@ -581,25 +585,26 @@ type readErrorConn struct {
 	net.Conn
 }
 
-func (r *readErrorConn) Read(p []byte) (int, error) {
+func (*readErrorConn) Read(_ []byte) (int, error) {
 	return 0, fmt.Errorf("error")
 }
 
-func (r *readErrorConn) Write(p []byte) (int, error) {
+func (*readErrorConn) Write(p []byte) (int, error) {
 	return len(p), nil
 }
 
-func (r *readErrorConn) Close() error {
+func (*readErrorConn) Close() error {
 	return nil
 }
 
-func (r *readErrorConn) LocalAddr() net.Addr {
+func (*readErrorConn) LocalAddr() net.Addr {
 	return nil
 }
 
-func (r *readErrorConn) RemoteAddr() net.Addr {
+func (*readErrorConn) RemoteAddr() net.Addr {
 	return nil
 }
+
 func Test_Client_Agent_RetryIf(t *testing.T) {
 	t.Parallel()
 
@@ -783,7 +788,10 @@ func Test_Client_Agent_MultipartForm_SendFiles(t *testing.T) {
 		buf := make([]byte, fh1.Size)
 		f, err := fh1.Open()
 		utils.AssertEqual(t, nil, err)
-		defer func() { _ = f.Close() }()
+		defer func() {
+			err := f.Close()
+			utils.AssertEqual(t, nil, err)
+		}()
 		_, err = f.Read(buf)
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, "form file", string(buf))
@@ -831,13 +839,16 @@ func checkFormFile(t *testing.T, fh *multipart.FileHeader, filename string) {
 	basename := filepath.Base(filename)
 	utils.AssertEqual(t, fh.Filename, basename)
 
-	b1, err := os.ReadFile(filename)
+	b1, err := os.ReadFile(filename) //nolint:gosec // We're in a test so reading user-provided files by name is fine
 	utils.AssertEqual(t, nil, err)
 
 	b2 := make([]byte, fh.Size)
 	f, err := fh.Open()
 	utils.AssertEqual(t, nil, err)
-	defer func() { _ = f.Close() }()
+	defer func() {
+		err := f.Close()
+		utils.AssertEqual(t, nil, err)
+	}()
 	_, err = f.Read(b2)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, b1, b2)
@@ -962,6 +973,7 @@ func Test_Client_Agent_InsecureSkipVerify(t *testing.T) {
 	cer, err := tls.LoadX509KeyPair("./.github/testdata/ssl.pem", "./.github/testdata/ssl.key")
 	utils.AssertEqual(t, nil, err)
 
+	//nolint:gosec // We're in a test so using old ciphers is fine
 	serverTLSConf := &tls.Config{
 		Certificates: []tls.Certificate{cer},
 	}
@@ -1137,7 +1149,7 @@ func Test_Client_Agent_Struct(t *testing.T) {
 		defer ReleaseAgent(a)
 		defer a.ConnectionClose()
 		request := a.Request()
-		request.Header.SetMethod("GET")
+		request.Header.SetMethod(MethodGet)
 		request.SetRequestURI("http://example.com")
 		err := a.Parse()
 		utils.AssertEqual(t, nil, err)
@@ -1198,8 +1210,8 @@ type errorMultipartWriter struct {
 	count int
 }
 
-func (e *errorMultipartWriter) Boundary() string           { return "myBoundary" }
-func (e *errorMultipartWriter) SetBoundary(_ string) error { return nil }
+func (*errorMultipartWriter) Boundary() string           { return "myBoundary" }
+func (*errorMultipartWriter) SetBoundary(_ string) error { return nil }
 func (e *errorMultipartWriter) CreateFormFile(_, _ string) (io.Writer, error) {
 	if e.count == 0 {
 		e.count++
@@ -1207,8 +1219,8 @@ func (e *errorMultipartWriter) CreateFormFile(_, _ string) (io.Writer, error) {
 	}
 	return errorWriter{}, nil
 }
-func (e *errorMultipartWriter) WriteField(_, _ string) error { return errors.New("WriteField error") }
-func (e *errorMultipartWriter) Close() error                 { return errors.New("Close error") }
+func (*errorMultipartWriter) WriteField(_, _ string) error { return errors.New("WriteField error") }
+func (*errorMultipartWriter) Close() error                 { return errors.New("Close error") }
 
 type errorWriter struct{}
 

color.go

@@ -53,6 +53,8 @@ type Colors struct {
 }
 
 // DefaultColors Default color codes
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var DefaultColors = Colors{
 	Black:   "\u001b[90m",
 	Red:     "\u001b[91m",

ctx.go

@@ -27,10 +27,16 @@ import (
 	"github.com/gofiber/fiber/v2/internal/dictpool"
 	"github.com/gofiber/fiber/v2/internal/schema"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/bytebufferpool"
 	"github.com/valyala/fasthttp"
 )
 
+const (
+	schemeHTTP  = "http"
+	schemeHTTPS = "https"
+)
+
 // maxParams defines the maximum number of parameters per route.
 const maxParams = 30
 
@@ -45,6 +51,7 @@ const (
 // userContextKey define the key name for storing context.Context in *fasthttp.RequestCtx
 const userContextKey = "__local_user_context__"
 
+//nolint:gochecknoglobals // TODO: Do not use global vars here
 var (
 	// decoderPoolMap helps to improve BodyParser's, QueryParser's and ReqHeaderParser's performance
 	decoderPoolMap = map[string]*sync.Pool{}
@@ -52,6 +59,7 @@ var (
 	tags = []string{queryTag, bodyTag, reqHeaderTag, paramsTag}
 )
 
+//nolint:gochecknoinits // init() is used to initialize a global map variable
 func init() {
 	for _, tag := range tags {
 		decoderPoolMap[tag] = &sync.Pool{New: func() interface{} {
@@ -100,9 +108,10 @@ type TLSHandler struct {
 }
 
 // GetClientInfo Callback function to set CHI
+// TODO: Why is this a getter which sets stuff?
 func (t *TLSHandler) GetClientInfo(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
 	t.clientHelloInfo = info
-	return nil, nil
+	return nil, nil //nolint:nilnil // Not returning anything useful here is probably fine
 }
 
 // Range data for c.Range
@@ -151,7 +160,10 @@ type ParserConfig struct {
 
 // AcquireCtx retrieves a new Ctx from the pool.
 func (app *App) AcquireCtx(fctx *fasthttp.RequestCtx) *Ctx {
-	c := app.pool.Get().(*Ctx)
+	c, ok := app.pool.Get().(*Ctx)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *Ctx"))
+	}
 	// Set app reference
 	c.app = app
 	// Reset route and handler index
@@ -388,7 +400,6 @@ func (c *Ctx) BodyParser(out interface{}) error {
 			} else {
 				data[k] = append(data[k], v)
 			}
-
 		})
 
 		return c.parseToStruct(bodyTag, out, data)
@@ -401,7 +412,10 @@ func (c *Ctx) BodyParser(out interface{}) error {
 		return c.parseToStruct(bodyTag, out, data.Value)
 	}
 	if strings.HasPrefix(ctype, MIMETextXML) || strings.HasPrefix(ctype, MIMEApplicationXML) {
-		return xml.Unmarshal(c.Body(), out)
+		if err := xml.Unmarshal(c.Body(), out); err != nil {
+			return fmt.Errorf("failed to unmarshal: %w", err)
+		}
+		return nil
 	}
 	// No suitable content type found
 	return ErrUnprocessableEntity
@@ -673,8 +687,11 @@ func (c *Ctx) Hostname() string {
 
 // Port returns the remote port of the request.
 func (c *Ctx) Port() string {
-	port := c.fasthttp.RemoteAddr().(*net.TCPAddr).Port
-	return strconv.Itoa(port)
+	tcpaddr, ok := c.fasthttp.RemoteAddr().(*net.TCPAddr)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *net.TCPAddr"))
+	}
+	return strconv.Itoa(tcpaddr.Port)
 }
 
 // IP returns the remote IP address of the request.
@@ -691,13 +708,16 @@ func (c *Ctx) IP() string {
 // extractIPsFromHeader will return a slice of IPs it found given a header name in the order they appear.
 // When IP validation is enabled, any invalid IPs will be omitted.
 func (c *Ctx) extractIPsFromHeader(header string) []string {
+	// TODO: Reuse the c.extractIPFromHeader func somehow in here
+
 	headerValue := c.Get(header)
 
 	// We can't know how many IPs we will return, but we will try to guess with this constant division.
 	// Counting ',' makes function slower for about 50ns in general case.
-	estimatedCount := len(headerValue) / 8
-	if estimatedCount > 8 {
-		estimatedCount = 8 // Avoid big allocation on big header
+	const maxEstimatedCount = 8
+	estimatedCount := len(headerValue) / maxEstimatedCount
+	if estimatedCount > maxEstimatedCount {
+		estimatedCount = maxEstimatedCount // Avoid big allocation on big header
 	}
 
 	ipsFound := make([]string, 0, estimatedCount)
@@ -707,11 +727,10 @@ func (c *Ctx) extractIPsFromHeader(header string) []string {
 
 iploop:
 	for {
-		v4 := false
-		v6 := false
+		var v4, v6 bool
 
 		// Manually splitting string without allocating slice, working with parts directly
-		i, j = j+1, j+2
+		i, j = j+1, j+2 //nolint:gomnd // Using these values is fine
 
 		if j > len(headerValue) {
 			break
@@ -758,9 +777,10 @@ func (c *Ctx) extractIPFromHeader(header string) string {
 
 	iploop:
 		for {
-			v4 := false
-			v6 := false
-			i, j = j+1, j+2
+			var v4, v6 bool
+
+			// Manually splitting string without allocating slice, working with parts directly
+			i, j = j+1, j+2 //nolint:gomnd // Using these values is fine
 
 			if j > len(headerValue) {
 				break
@@ -793,14 +813,14 @@ func (c *Ctx) extractIPFromHeader(header string) string {
 		return c.fasthttp.RemoteIP().String()
 	}
 
-	// default behaviour if IP validation is not enabled is just to return whatever value is
+	// default behavior if IP validation is not enabled is just to return whatever value is
 	// in the proxy header. Even if it is empty or invalid
 	return c.Get(c.app.config.ProxyHeader)
 }
 
 // IPs returns a string slice of IP addresses specified in the X-Forwarded-For request header.
 // When IP validation is enabled, only valid IPs are returned.
-func (c *Ctx) IPs() (ips []string) {
+func (c *Ctx) IPs() []string {
 	return c.extractIPsFromHeader(HeaderXForwardedFor)
 }
 
@@ -839,7 +859,7 @@ func (c *Ctx) JSON(data interface{}) error {
 func (c *Ctx) JSONP(data interface{}, callback ...string) error {
 	raw, err := json.Marshal(data)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to marshal: %w", err)
 	}
 
 	var result, cb string
@@ -877,11 +897,11 @@ func (c *Ctx) Links(link ...string) {
 	bb := bytebufferpool.Get()
 	for i := range link {
 		if i%2 == 0 {
-			_ = bb.WriteByte('<')
-			_, _ = bb.WriteString(link[i])
-			_ = bb.WriteByte('>')
+			_ = bb.WriteByte('<')          //nolint:errcheck // This will never fail
+			_, _ = bb.WriteString(link[i]) //nolint:errcheck // This will never fail
+			_ = bb.WriteByte('>')          //nolint:errcheck // This will never fail
 		} else {
-			_, _ = bb.WriteString(`; rel="` + link[i] + `",`)
+			_, _ = bb.WriteString(`; rel="` + link[i] + `",`) //nolint:errcheck // This will never fail
 		}
 	}
 	c.setCanonical(HeaderLink, utils.TrimRight(c.app.getString(bb.Bytes()), ','))
@@ -890,7 +910,7 @@ func (c *Ctx) Links(link ...string) {
 
 // Locals makes it possible to pass interface{} values under keys scoped to the request
 // and therefore available to all following routes that match the request.
-func (c *Ctx) Locals(key interface{}, value ...interface{}) (val interface{}) {
+func (c *Ctx) Locals(key interface{}, value ...interface{}) interface{} {
 	if len(value) == 0 {
 		return c.fasthttp.UserValue(key)
 	}
@@ -933,9 +953,10 @@ func (c *Ctx) ClientHelloInfo() *tls.ClientHelloInfo {
 }
 
 // Next executes the next method in the stack that matches the current route.
-func (c *Ctx) Next() (err error) {
+func (c *Ctx) Next() error {
 	// Increment handler index
 	c.indexHandler++
+	var err error
 	// Did we executed all route handlers?
 	if c.indexHandler < len(c.route.Handlers) {
 		// Continue route stack
@@ -947,7 +968,7 @@ func (c *Ctx) Next() (err error) {
 	return err
 }
 
-// RestartRouting instead of going to the next handler. This may be usefull after
+// RestartRouting instead of going to the next handler. This may be useful after
 // changing the request path. Note that handlers might be executed again.
 func (c *Ctx) RestartRouting() error {
 	c.indexRoute = -1
@@ -1017,9 +1038,8 @@ func (c *Ctx) ParamsInt(key string, defaultValue ...int) (int, error) {
 	if err != nil {
 		if len(defaultValue) > 0 {
 			return defaultValue[0], nil
-		} else {
-			return 0, err
 		}
+		return 0, fmt.Errorf("failed to convert: %w", err)
 	}
 
 	return value, nil
@@ -1044,15 +1064,16 @@ func (c *Ctx) Path(override ...string) string {
 // Please use Config.EnableTrustedProxyCheck to prevent header spoofing, in case when your app is behind the proxy.
 func (c *Ctx) Protocol() string {
 	if c.fasthttp.IsTLS() {
-		return "https"
+		return schemeHTTPS
 	}
 	if !c.IsProxyTrusted() {
-		return "http"
+		return schemeHTTP
 	}
 
-	scheme := "http"
+	scheme := schemeHTTP
+	const lenXHeaderName = 12
 	c.fasthttp.Request.Header.VisitAll(func(key, val []byte) {
-		if len(key) < 12 {
+		if len(key) < lenXHeaderName {
 			return // Neither "X-Forwarded-" nor "X-Url-Scheme"
 		}
 		switch {
@@ -1067,7 +1088,7 @@ func (c *Ctx) Protocol() string {
 					scheme = v
 				}
 			} else if bytes.Equal(key, []byte(HeaderXForwardedSsl)) && bytes.Equal(val, []byte("on")) {
-				scheme = "https"
+				scheme = schemeHTTPS
 			}
 
 		case bytes.Equal(key, []byte(HeaderXUrlScheme)):
@@ -1100,9 +1121,8 @@ func (c *Ctx) QueryInt(key string, defaultValue ...int) int {
 	if err != nil {
 		if len(defaultValue) > 0 {
 			return defaultValue[0]
-		} else {
-			return 0
 		}
+		return 0
 	}
 
 	return value
@@ -1133,7 +1153,6 @@ func (c *Ctx) QueryParser(out interface{}) error {
 		} else {
 			data[k] = append(data[k], v)
 		}
-
 	})
 
 	if err != nil {
@@ -1150,10 +1169,9 @@ func parseParamSquareBrackets(k string) (string, error) {
 	kbytes := []byte(k)
 
 	for i, b := range kbytes {
-
 		if b == '[' && kbytes[i+1] != ']' {
 			if err := bb.WriteByte('.'); err != nil {
-				return "", err
+				return "", fmt.Errorf("failed to write: %w", err)
 			}
 		}
 
@@ -1162,7 +1180,7 @@ func parseParamSquareBrackets(k string) (string, error) {
 		}
 
 		if err := bb.WriteByte(b); err != nil {
-			return "", err
+			return "", fmt.Errorf("failed to write: %w", err)
 		}
 	}
 
@@ -1184,21 +1202,27 @@ func (c *Ctx) ReqHeaderParser(out interface{}) error {
 		} else {
 			data[k] = append(data[k], v)
 		}
-
 	})
 
 	return c.parseToStruct(reqHeaderTag, out, data)
 }
 
-func (c *Ctx) parseToStruct(aliasTag string, out interface{}, data map[string][]string) error {
+func (*Ctx) parseToStruct(aliasTag string, out interface{}, data map[string][]string) error {
 	// Get decoder from pool
-	schemaDecoder := decoderPoolMap[aliasTag].Get().(*schema.Decoder)
+	schemaDecoder, ok := decoderPoolMap[aliasTag].Get().(*schema.Decoder)
+	if !ok {
+		panic(fmt.Errorf("failed to type-assert to *schema.Decoder"))
+	}
 	defer decoderPoolMap[aliasTag].Put(schemaDecoder)
 
 	// Set alias tag
 	schemaDecoder.SetAliasTag(aliasTag)
 
-	return schemaDecoder.Decode(out, data)
+	if err := schemaDecoder.Decode(out, data); err != nil {
+		return fmt.Errorf("failed to decode: %w", err)
+	}
+
+	return nil
 }
 
 func equalFieldType(out interface{}, kind reflect.Kind, key string) bool {
@@ -1248,24 +1272,23 @@ var (
 )
 
 // Range returns a struct containing the type and a slice of ranges.
-func (c *Ctx) Range(size int) (rangeData Range, err error) {
+func (c *Ctx) Range(size int) (Range, error) {
+	var rangeData Range
 	rangeStr := c.Get(HeaderRange)
 	if rangeStr == "" || !strings.Contains(rangeStr, "=") {
-		err = ErrRangeMalformed
-		return
+		return rangeData, ErrRangeMalformed
 	}
 	data := strings.Split(rangeStr, "=")
-	if len(data) != 2 {
-		err = ErrRangeMalformed
-		return
+	const expectedDataParts = 2
+	if len(data) != expectedDataParts {
+		return rangeData, ErrRangeMalformed
 	}
 	rangeData.Type = data[0]
 	arr := strings.Split(data[1], ",")
 	for i := 0; i < len(arr); i++ {
 		item := strings.Split(arr[i], "-")
 		if len(item) == 1 {
-			err = ErrRangeMalformed
-			return
+			return rangeData, ErrRangeMalformed
 		}
 		start, startErr := strconv.Atoi(item[0])
 		end, endErr := strconv.Atoi(item[1])
@@ -1290,11 +1313,10 @@ func (c *Ctx) Range(size int) (rangeData Range, err error) {
 		})
 	}
 	if len(rangeData.Ranges) < 1 {
-		err = ErrRangeUnsatisfiable
-		return
+		return rangeData, ErrRangeUnsatisfiable
 	}
 
-	return
+	return rangeData, nil
 }
 
 // Redirect to the URL derived from the specified path, with specified status.
@@ -1330,7 +1352,7 @@ func (c *Ctx) getLocationFromRoute(route Route, params Map) (string, error) {
 		if !segment.IsParam {
 			_, err := buf.WriteString(segment.Const)
 			if err != nil {
-				return "", err
+				return "", fmt.Errorf("failed to write string: %w", err)
 			}
 			continue
 		}
@@ -1341,7 +1363,7 @@ func (c *Ctx) getLocationFromRoute(route Route, params Map) (string, error) {
 			if isSame || isGreedy {
 				_, err := buf.WriteString(utils.ToString(val))
 				if err != nil {
-					return "", err
+					return "", fmt.Errorf("failed to write string: %w", err)
 				}
 			}
 		}
@@ -1373,10 +1395,10 @@ func (c *Ctx) RedirectToRoute(routeName string, params Map, status ...int) error
 
 		i := 1
 		for k, v := range queries {
-			_, _ = queryText.WriteString(k + "=" + v)
+			_, _ = queryText.WriteString(k + "=" + v) //nolint:errcheck // This will never fail
 
 			if i != len(queries) {
-				_, _ = queryText.WriteString("&")
+				_, _ = queryText.WriteString("&") //nolint:errcheck // This will never fail
 			}
 			i++
 		}
@@ -1399,7 +1421,6 @@ func (c *Ctx) RedirectBack(fallback string, status ...int) error {
 // Render a template with data and sends a text/html response.
 // We support the following engines: html, amber, handlebars, mustache, pug
 func (c *Ctx) Render(name string, bind interface{}, layouts ...string) error {
-	var err error
 	// Get new buffer from pool
 	buf := bytebufferpool.Get()
 	defer bytebufferpool.Put(buf)
@@ -1421,7 +1442,7 @@ func (c *Ctx) Render(name string, bind interface{}, layouts ...string) error {
 			// Render template from Views
 			if app.config.Views != nil {
 				if err := app.config.Views.Render(buf, name, bind, layouts...); err != nil {
-					return err
+					return fmt.Errorf("failed to render: %w", err)
 				}
 
 				rendered = true
@@ -1433,17 +1454,18 @@ func (c *Ctx) Render(name string, bind interface{}, layouts ...string) error {
 	if !rendered {
 		// Render raw template using 'name' as filepath if no engine is set
 		var tmpl *template.Template
-		if _, err = readContent(buf, name); err != nil {
+		if _, err := readContent(buf, name); err != nil {
 			return err
 		}
 		// Parse template
-		if tmpl, err = template.New("").Parse(c.app.getString(buf.Bytes())); err != nil {
-			return err
+		tmpl, err := template.New("").Parse(c.app.getString(buf.Bytes()))
+		if err != nil {
+			return fmt.Errorf("failed to parse: %w", err)
 		}
 		buf.Reset()
 		// Render template
-		if err = tmpl.Execute(buf, bind); err != nil {
-			return err
+		if err := tmpl.Execute(buf, bind); err != nil {
+			return fmt.Errorf("failed to execute: %w", err)
 		}
 	}
 
@@ -1451,8 +1473,8 @@ func (c *Ctx) Render(name string, bind interface{}, layouts ...string) error {
 	c.fasthttp.Response.Header.SetContentType(MIMETextHTMLCharsetUTF8)
 	// Set rendered template to body
 	c.fasthttp.Response.SetBody(buf.Bytes())
-	// Return err if exist
-	return err
+
+	return nil
 }
 
 func (c *Ctx) renderExtensions(bind interface{}) {
@@ -1501,28 +1523,32 @@ func (c *Ctx) Route() *Route {
 }
 
 // SaveFile saves any multipart file to disk.
-func (c *Ctx) SaveFile(fileheader *multipart.FileHeader, path string) error {
+func (*Ctx) SaveFile(fileheader *multipart.FileHeader, path string) error {
 	return fasthttp.SaveMultipartFile(fileheader, path)
 }
 
 // SaveFileToStorage saves any multipart file to an external storage system.
-func (c *Ctx) SaveFileToStorage(fileheader *multipart.FileHeader, path string, storage Storage) error {
+func (*Ctx) SaveFileToStorage(fileheader *multipart.FileHeader, path string, storage Storage) error {
 	file, err := fileheader.Open()
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to open: %w", err)
 	}
 
 	content, err := io.ReadAll(file)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to read: %w", err)
 	}
 
-	return storage.Set(path, content, 0)
+	if err := storage.Set(path, content, 0); err != nil {
+		return fmt.Errorf("failed to store: %w", err)
+	}
+
+	return nil
 }
 
 // Secure returns whether a secure connection was established.
 func (c *Ctx) Secure() bool {
-	return c.Protocol() == "https"
+	return c.Protocol() == schemeHTTPS
 }
 
 // Send sets the HTTP response body without copying it.
@@ -1533,6 +1559,7 @@ func (c *Ctx) Send(body []byte) error {
 	return nil
 }
 
+//nolint:gochecknoglobals // TODO: Do not use global vars here
 var (
 	sendFileOnce    sync.Once
 	sendFileFS      *fasthttp.FS
@@ -1548,6 +1575,7 @@ func (c *Ctx) SendFile(file string, compress ...bool) error {
 
 	// https://github.com/valyala/fasthttp/blob/c7576cc10cabfc9c993317a2d3f8355497bea156/fs.go#L129-L134
 	sendFileOnce.Do(func() {
+		const cacheDuration = 10 * time.Second
 		sendFileFS = &fasthttp.FS{
 			Root:                 "",
 			AllowEmptyRoot:       true,
@@ -1555,7 +1583,7 @@ func (c *Ctx) SendFile(file string, compress ...bool) error {
 			AcceptByteRange:      true,
 			Compress:             true,
 			CompressedFileSuffix: c.app.config.CompressedFileSuffix,
-			CacheDuration:        10 * time.Second,
+			CacheDuration:        cacheDuration,
 			IndexNames:           []string{"index.html"},
 			PathNotFound: func(ctx *fasthttp.RequestCtx) {
 				ctx.Response.SetStatusCode(StatusNotFound)
@@ -1579,7 +1607,7 @@ func (c *Ctx) SendFile(file string, compress ...bool) error {
 		var err error
 		file = filepath.FromSlash(file)
 		if file, err = filepath.Abs(file); err != nil {
-			return err
+			return fmt.Errorf("failed to determine abs file path: %w", err)
 		}
 		if hasTrailingSlash {
 			file += "/"
@@ -1644,11 +1672,11 @@ func (c *Ctx) SendStream(stream io.Reader, size ...int) error {
 }
 
 // Set sets the response's HTTP header field to the specified key, value.
-func (c *Ctx) Set(key string, val string) {
+func (c *Ctx) Set(key, val string) {
 	c.fasthttp.Response.Header.Set(key, val)
 }
 
-func (c *Ctx) setCanonical(key string, val string) {
+func (c *Ctx) setCanonical(key, val string) {
 	c.fasthttp.Response.Header.SetCanonical(c.app.getBytes(key), c.app.getBytes(val))
 }
 
@@ -1719,6 +1747,7 @@ func (c *Ctx) Write(p []byte) (int, error) {
 
 // Writef appends f & a into response body writer.
 func (c *Ctx) Writef(f string, a ...interface{}) (int, error) {
+	//nolint:wrapcheck // This must not be wrapped
 	return fmt.Fprintf(c.fasthttp.Response.BodyWriter(), f, a...)
 }
 
@@ -1760,8 +1789,9 @@ func (c *Ctx) configDependentPaths() {
 	// Define the path for dividing routes into areas for fast tree detection, so that fewer routes need to be traversed,
 	// since the first three characters area select a list of routes
 	c.treePath = c.treePath[0:0]
-	if len(c.detectionPath) >= 3 {
-		c.treePath = c.detectionPath[:3]
+	const maxDetectionPaths = 3
+	if len(c.detectionPath) >= maxDetectionPaths {
+		c.treePath = c.detectionPath[:maxDetectionPaths]
 	}
 }
 
@@ -1786,7 +1816,7 @@ func (c *Ctx) IsProxyTrusted() bool {
 }
 
 // IsLocalHost will return true if address is a localhost address.
-func (c *Ctx) isLocalHost(address string) bool {
+func (*Ctx) isLocalHost(address string) bool {
 	localHosts := []string{"127.0.0.1", "0.0.0.0", "::1"}
 	for _, h := range localHosts {
 		if strings.Contains(address, h) {

ctx_test.go

@@ -2,6 +2,7 @@
 // 🤖 Github Repository: https://github.com/gofiber/fiber
 // 📌 API Documentation: https://docs.gofiber.io
 
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package fiber
 
 import (
@@ -28,6 +29,7 @@ import (
 
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/bytebufferpool"
 	"github.com/valyala/fasthttp"
 )
@@ -361,8 +363,10 @@ func Test_Ctx_BodyParser(t *testing.T) {
 	{
 		var gzipJSON bytes.Buffer
 		w := gzip.NewWriter(&gzipJSON)
-		_, _ = w.Write([]byte(`{"name":"john"}`))
-		_ = w.Close()
+		_, err := w.Write([]byte(`{"name":"john"}`))
+		utils.AssertEqual(t, nil, err)
+		err = w.Close()
+		utils.AssertEqual(t, nil, err)
 
 		c.Request().Header.SetContentType(MIMEApplicationJSON)
 		c.Request().Header.Set(HeaderContentEncoding, "gzip")
@@ -431,9 +435,7 @@ func Test_Ctx_ParamParser(t *testing.T) {
 			UserID uint `params:"userId"`
 			RoleID uint `params:"roleId"`
 		}
-		var (
-			d = new(Demo)
-		)
+		d := new(Demo)
 		if err := ctx.ParamsParser(d); err != nil {
 			t.Fatal(err)
 		}
@@ -519,7 +521,7 @@ func Benchmark_Ctx_BodyParser_JSON(b *testing.B) {
 	b.ResetTimer()
 
 	for n := 0; n < b.N; n++ {
-		_ = c.BodyParser(d)
+		_ = c.BodyParser(d) //nolint:errcheck // It is fine to ignore the error here as we check it once further below
 	}
 	utils.AssertEqual(b, nil, c.BodyParser(d))
 	utils.AssertEqual(b, "john", d.Name)
@@ -543,7 +545,7 @@ func Benchmark_Ctx_BodyParser_XML(b *testing.B) {
 	b.ResetTimer()
 
 	for n := 0; n < b.N; n++ {
-		_ = c.BodyParser(d)
+		_ = c.BodyParser(d) //nolint:errcheck // It is fine to ignore the error here as we check it once further below
 	}
 	utils.AssertEqual(b, nil, c.BodyParser(d))
 	utils.AssertEqual(b, "john", d.Name)
@@ -567,7 +569,7 @@ func Benchmark_Ctx_BodyParser_Form(b *testing.B) {
 	b.ResetTimer()
 
 	for n := 0; n < b.N; n++ {
-		_ = c.BodyParser(d)
+		_ = c.BodyParser(d) //nolint:errcheck // It is fine to ignore the error here as we check it once further below
 	}
 	utils.AssertEqual(b, nil, c.BodyParser(d))
 	utils.AssertEqual(b, "john", d.Name)
@@ -592,7 +594,7 @@ func Benchmark_Ctx_BodyParser_MultipartForm(b *testing.B) {
 	b.ResetTimer()
 
 	for n := 0; n < b.N; n++ {
-		_ = c.BodyParser(d)
+		_ = c.BodyParser(d) //nolint:errcheck // It is fine to ignore the error here as we check it once further below
 	}
 	utils.AssertEqual(b, nil, c.BodyParser(d))
 	utils.AssertEqual(b, "john", d.Name)
@@ -879,12 +881,13 @@ func Test_Ctx_FormFile(t *testing.T) {
 
 		f, err := fh.Open()
 		utils.AssertEqual(t, nil, err)
+		defer func() {
+			utils.AssertEqual(t, nil, f.Close())
+		}()
 
 		b := new(bytes.Buffer)
 		_, err = io.Copy(b, f)
 		utils.AssertEqual(t, nil, err)
-
-		f.Close()
 		utils.AssertEqual(t, "hello world", b.String())
 		return nil
 	})
@@ -897,8 +900,7 @@ func Test_Ctx_FormFile(t *testing.T) {
 
 	_, err = ioWriter.Write([]byte("hello world"))
 	utils.AssertEqual(t, nil, err)
-
-	writer.Close()
+	utils.AssertEqual(t, nil, writer.Close())
 
 	req := httptest.NewRequest(MethodPost, "/test", body)
 	req.Header.Set(HeaderContentType, writer.FormDataContentType())
@@ -921,10 +923,9 @@ func Test_Ctx_FormValue(t *testing.T) {
 
 	body := &bytes.Buffer{}
 	writer := multipart.NewWriter(body)
-
 	utils.AssertEqual(t, nil, writer.WriteField("name", "john"))
+	utils.AssertEqual(t, nil, writer.Close())
 
-	writer.Close()
 	req := httptest.NewRequest(MethodPost, "/test", body)
 	req.Header.Set("Content-Type", fmt.Sprintf("multipart/form-data; boundary=%s", writer.Boundary()))
 	req.Header.Set("Content-Length", strconv.Itoa(len(body.Bytes())))
@@ -1240,7 +1241,7 @@ func Test_Ctx_IP(t *testing.T) {
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
 
-	// default behaviour will return the remote IP from the stack
+	// default behavior will return the remote IP from the stack
 	utils.AssertEqual(t, "0.0.0.0", c.IP())
 
 	// X-Forwarded-For is set, but it is ignored because proxyHeader is not set
@@ -1252,7 +1253,7 @@ func Test_Ctx_IP(t *testing.T) {
 func Test_Ctx_IP_ProxyHeader(t *testing.T) {
 	t.Parallel()
 
-	// make sure that the same behaviour exists for different proxy header names
+	// make sure that the same behavior exists for different proxy header names
 	proxyHeaderNames := []string{"Real-Ip", HeaderXForwardedFor}
 
 	for _, proxyHeaderName := range proxyHeaderNames {
@@ -1286,7 +1287,7 @@ func Test_Ctx_IP_ProxyHeader(t *testing.T) {
 func Test_Ctx_IP_ProxyHeader_With_IP_Validation(t *testing.T) {
 	t.Parallel()
 
-	// make sure that the same behaviour exists for different proxy header names
+	// make sure that the same behavior exists for different proxy header names
 	proxyHeaderNames := []string{"Real-Ip", HeaderXForwardedFor}
 
 	for _, proxyHeaderName := range proxyHeaderNames {
@@ -1625,35 +1626,43 @@ func Test_Ctx_ClientHelloInfo(t *testing.T) {
 	})
 
 	// Test without TLS handler
-	resp, _ := app.Test(httptest.NewRequest(MethodGet, "/ServerName", nil))
-	body, _ := io.ReadAll(resp.Body)
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/ServerName", nil))
+	utils.AssertEqual(t, nil, err)
+	body, err := io.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, []byte("ClientHelloInfo is nil"), body)
 
 	// Test with TLS Handler
 	const (
-		PSSWithSHA256 = 0x0804
-		VersionTLS13  = 0x0304
+		pssWithSHA256 = 0x0804
+		versionTLS13  = 0x0304
 	)
 	app.tlsHandler = &TLSHandler{clientHelloInfo: &tls.ClientHelloInfo{
 		ServerName:        "example.golang",
-		SignatureSchemes:  []tls.SignatureScheme{PSSWithSHA256},
-		SupportedVersions: []uint16{VersionTLS13},
+		SignatureSchemes:  []tls.SignatureScheme{pssWithSHA256},
+		SupportedVersions: []uint16{versionTLS13},
 	}}
 
 	// Test ServerName
-	resp, _ = app.Test(httptest.NewRequest(MethodGet, "/ServerName", nil))
-	body, _ = io.ReadAll(resp.Body)
+	resp, err = app.Test(httptest.NewRequest(MethodGet, "/ServerName", nil))
+	utils.AssertEqual(t, nil, err)
+	body, err = io.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, []byte("example.golang"), body)
 
 	// Test SignatureSchemes
-	resp, _ = app.Test(httptest.NewRequest(MethodGet, "/SignatureSchemes", nil))
-	body, _ = io.ReadAll(resp.Body)
-	utils.AssertEqual(t, "["+strconv.Itoa(PSSWithSHA256)+"]", string(body))
+	resp, err = app.Test(httptest.NewRequest(MethodGet, "/SignatureSchemes", nil))
+	utils.AssertEqual(t, nil, err)
+	body, err = io.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, "["+strconv.Itoa(pssWithSHA256)+"]", string(body))
 
 	// Test SupportedVersions
-	resp, _ = app.Test(httptest.NewRequest(MethodGet, "/SupportedVersions", nil))
-	body, _ = io.ReadAll(resp.Body)
-	utils.AssertEqual(t, "["+strconv.Itoa(VersionTLS13)+"]", string(body))
+	resp, err = app.Test(httptest.NewRequest(MethodGet, "/SupportedVersions", nil))
+	utils.AssertEqual(t, nil, err)
+	body, err = io.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, "["+strconv.Itoa(versionTLS13)+"]", string(body))
 }
 
 // go test -run Test_Ctx_InvalidMethod
@@ -1688,10 +1697,9 @@ func Test_Ctx_MultipartForm(t *testing.T) {
 
 	body := &bytes.Buffer{}
 	writer := multipart.NewWriter(body)
-
 	utils.AssertEqual(t, nil, writer.WriteField("name", "john"))
+	utils.AssertEqual(t, nil, writer.Close())
 
-	writer.Close()
 	req := httptest.NewRequest(MethodPost, "/test", body)
 	req.Header.Set(HeaderContentType, fmt.Sprintf("multipart/form-data; boundary=%s", writer.Boundary()))
 	req.Header.Set(HeaderContentLength, strconv.Itoa(len(body.Bytes())))
@@ -1706,8 +1714,8 @@ func Benchmark_Ctx_MultipartForm(b *testing.B) {
 	app := New()
 
 	app.Post("/", func(c *Ctx) error {
-		_, _ = c.MultipartForm()
-		return nil
+		_, err := c.MultipartForm()
+		return err
 	})
 
 	c := &fasthttp.RequestCtx{}
@@ -1889,11 +1897,16 @@ func Benchmark_Ctx_AllParams(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		res = c.AllParams()
 	}
-	utils.AssertEqual(b, map[string]string{"param1": "john",
-		"param2": "doe",
-		"param3": "is",
-		"param4": "awesome"},
-		res)
+	utils.AssertEqual(
+		b,
+		map[string]string{
+			"param1": "john",
+			"param2": "doe",
+			"param3": "is",
+			"param4": "awesome",
+		},
+		res,
+	)
 }
 
 // go test -v -run=^$ -bench=Benchmark_Ctx_ParamsParse -benchmem -count=4
@@ -1964,31 +1977,31 @@ func Test_Ctx_Protocol(t *testing.T) {
 
 	c := app.AcquireCtx(freq)
 	defer app.ReleaseCtx(c)
-	c.Request().Header.Set(HeaderXForwardedProto, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProto, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXForwardedProtocol, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProtocol, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedProto, "https, http")
-	utils.AssertEqual(t, "https", c.Protocol())
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedProtocol, "https, http")
-	utils.AssertEqual(t, "https", c.Protocol())
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedSsl, "on")
-	utils.AssertEqual(t, "https", c.Protocol())
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXUrlScheme, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXUrlScheme, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 }
 
 // go test -v -run=^$ -bench=Benchmark_Ctx_Protocol -benchmem -count=4
@@ -2002,7 +2015,7 @@ func Benchmark_Ctx_Protocol(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		res = c.Protocol()
 	}
-	utils.AssertEqual(b, "http", res)
+	utils.AssertEqual(b, schemeHTTP, res)
 }
 
 // go test -run Test_Ctx_Protocol_TrustedProxy
@@ -2012,23 +2025,23 @@ func Test_Ctx_Protocol_TrustedProxy(t *testing.T) {
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
 
-	c.Request().Header.Set(HeaderXForwardedProto, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProto, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXForwardedProtocol, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProtocol, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedSsl, "on")
-	utils.AssertEqual(t, "https", c.Protocol())
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXUrlScheme, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXUrlScheme, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 }
 
 // go test -run Test_Ctx_Protocol_TrustedProxyRange
@@ -2038,23 +2051,23 @@ func Test_Ctx_Protocol_TrustedProxyRange(t *testing.T) {
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
 
-	c.Request().Header.Set(HeaderXForwardedProto, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProto, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXForwardedProtocol, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProtocol, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedSsl, "on")
-	utils.AssertEqual(t, "https", c.Protocol())
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXUrlScheme, "https")
-	utils.AssertEqual(t, "https", c.Protocol())
+	c.Request().Header.Set(HeaderXUrlScheme, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTPS, c.Protocol())
 	c.Request().Header.Reset()
 
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 }
 
 // go test -run Test_Ctx_Protocol_UntrustedProxyRange
@@ -2064,23 +2077,23 @@ func Test_Ctx_Protocol_UntrustedProxyRange(t *testing.T) {
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
 
-	c.Request().Header.Set(HeaderXForwardedProto, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProto, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXForwardedProtocol, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProtocol, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedSsl, "on")
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXUrlScheme, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXUrlScheme, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 }
 
 // go test -run Test_Ctx_Protocol_UnTrustedProxy
@@ -2090,23 +2103,23 @@ func Test_Ctx_Protocol_UnTrustedProxy(t *testing.T) {
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
 
-	c.Request().Header.Set(HeaderXForwardedProto, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProto, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXForwardedProtocol, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXForwardedProtocol, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
 	c.Request().Header.Set(HeaderXForwardedSsl, "on")
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	c.Request().Header.Set(HeaderXUrlScheme, "https")
-	utils.AssertEqual(t, "http", c.Protocol())
+	c.Request().Header.Set(HeaderXUrlScheme, schemeHTTPS)
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 	c.Request().Header.Reset()
 
-	utils.AssertEqual(t, "http", c.Protocol())
+	utils.AssertEqual(t, schemeHTTP, c.Protocol())
 }
 
 // go test -run Test_Ctx_Query
@@ -2224,7 +2237,12 @@ func Test_Ctx_SaveFile(t *testing.T) {
 		tempFile, err := os.CreateTemp(os.TempDir(), "test-")
 		utils.AssertEqual(t, nil, err)
 
-		defer os.Remove(tempFile.Name())
+		defer func(file *os.File) {
+			err := file.Close()
+			utils.AssertEqual(t, nil, err)
+			err = os.Remove(file.Name())
+			utils.AssertEqual(t, nil, err)
+		}(tempFile)
 		err = c.SaveFile(fh, tempFile.Name())
 		utils.AssertEqual(t, nil, err)
 
@@ -2242,7 +2260,7 @@ func Test_Ctx_SaveFile(t *testing.T) {
 
 	_, err = ioWriter.Write([]byte("hello world"))
 	utils.AssertEqual(t, nil, err)
-	writer.Close()
+	utils.AssertEqual(t, nil, writer.Close())
 
 	req := httptest.NewRequest(MethodPost, "/test", body)
 	req.Header.Set("Content-Type", writer.FormDataContentType())
@@ -2284,7 +2302,7 @@ func Test_Ctx_SaveFileToStorage(t *testing.T) {
 
 	_, err = ioWriter.Write([]byte("hello world"))
 	utils.AssertEqual(t, nil, err)
-	writer.Close()
+	utils.AssertEqual(t, nil, writer.Close())
 
 	req := httptest.NewRequest(MethodPost, "/test", body)
 	req.Header.Set("Content-Type", writer.FormDataContentType())
@@ -2370,7 +2388,9 @@ func Test_Ctx_Download(t *testing.T) {
 
 	f, err := os.Open("./ctx.go")
 	utils.AssertEqual(t, nil, err)
-	defer f.Close()
+	defer func() {
+		utils.AssertEqual(t, nil, f.Close())
+	}()
 
 	expect, err := io.ReadAll(f)
 	utils.AssertEqual(t, nil, err)
@@ -2389,7 +2409,9 @@ func Test_Ctx_SendFile(t *testing.T) {
 	// fetch file content
 	f, err := os.Open("./ctx.go")
 	utils.AssertEqual(t, nil, err)
-	defer f.Close()
+	defer func() {
+		utils.AssertEqual(t, nil, f.Close())
+	}()
 	expectFileContent, err := io.ReadAll(f)
 	utils.AssertEqual(t, nil, err)
 	// fetch file info for the not modified test case
@@ -2435,7 +2457,7 @@ func Test_Ctx_SendFile_404(t *testing.T) {
 		return err
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, StatusNotFound, resp.StatusCode)
 }
@@ -2473,11 +2495,11 @@ func Test_Ctx_SendFile_Immutable(t *testing.T) {
 	for _, endpoint := range endpointsForTest {
 		t.Run(endpoint, func(t *testing.T) {
 			// 1st try
-			resp, err := app.Test(httptest.NewRequest("GET", endpoint, nil))
+			resp, err := app.Test(httptest.NewRequest(MethodGet, endpoint, nil))
 			utils.AssertEqual(t, nil, err)
 			utils.AssertEqual(t, StatusOK, resp.StatusCode)
 			// 2nd try
-			resp, err = app.Test(httptest.NewRequest("GET", endpoint, nil))
+			resp, err = app.Test(httptest.NewRequest(MethodGet, endpoint, nil))
 			utils.AssertEqual(t, nil, err)
 			utils.AssertEqual(t, StatusOK, resp.StatusCode)
 		})
@@ -2495,9 +2517,9 @@ func Test_Ctx_SendFile_RestoreOriginalURL(t *testing.T) {
 		return err
 	})
 
-	_, err1 := app.Test(httptest.NewRequest("GET", "/?test=true", nil))
+	_, err1 := app.Test(httptest.NewRequest(MethodGet, "/?test=true", nil))
 	// second request required to confirm with zero allocation
-	_, err2 := app.Test(httptest.NewRequest("GET", "/?test=true", nil))
+	_, err2 := app.Test(httptest.NewRequest(MethodGet, "/?test=true", nil))
 
 	utils.AssertEqual(t, nil, err1)
 	utils.AssertEqual(t, nil, err2)
@@ -2893,12 +2915,12 @@ func Test_Ctx_Render(t *testing.T) {
 	err := c.Render("./.github/testdata/index.tmpl", Map{
 		"Title": "Hello, World!",
 	})
+	utils.AssertEqual(t, nil, err)
 
 	buf := bytebufferpool.Get()
-	_, _ = buf.WriteString("overwrite")
+	_, _ = buf.WriteString("overwrite") //nolint:errcheck // This will never fail
 	defer bytebufferpool.Put(buf)
 
-	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(c.Response().Body()))
 
 	err = c.Render("./.github/testdata/template-non-exists.html", nil)
@@ -2918,12 +2940,12 @@ func Test_Ctx_RenderWithoutLocals(t *testing.T) {
 	c.Locals("Title", "Hello, World!")
 	defer app.ReleaseCtx(c)
 	err := c.Render("./.github/testdata/index.tmpl", Map{})
+	utils.AssertEqual(t, nil, err)
 
 	buf := bytebufferpool.Get()
-	_, _ = buf.WriteString("overwrite")
+	_, _ = buf.WriteString("overwrite") //nolint:errcheck // This will never fail
 	defer bytebufferpool.Put(buf)
 
-	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1><no value></h1>", string(c.Response().Body()))
 }
 
@@ -2937,14 +2959,13 @@ func Test_Ctx_RenderWithLocals(t *testing.T) {
 	c.Locals("Title", "Hello, World!")
 	defer app.ReleaseCtx(c)
 	err := c.Render("./.github/testdata/index.tmpl", Map{})
+	utils.AssertEqual(t, nil, err)
 
 	buf := bytebufferpool.Get()
-	_, _ = buf.WriteString("overwrite")
+	_, _ = buf.WriteString("overwrite") //nolint:errcheck // This will never fail
 	defer bytebufferpool.Put(buf)
 
-	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(c.Response().Body()))
-
 }
 
 func Test_Ctx_RenderWithBind(t *testing.T) {
@@ -2959,14 +2980,13 @@ func Test_Ctx_RenderWithBind(t *testing.T) {
 	utils.AssertEqual(t, nil, err)
 	defer app.ReleaseCtx(c)
 	err = c.Render("./.github/testdata/index.tmpl", Map{})
+	utils.AssertEqual(t, nil, err)
 
 	buf := bytebufferpool.Get()
-	_, _ = buf.WriteString("overwrite")
+	_, _ = buf.WriteString("overwrite") //nolint:errcheck // This will never fail
 	defer bytebufferpool.Put(buf)
 
-	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(c.Response().Body()))
-
 }
 
 func Test_Ctx_RenderWithOverwrittenBind(t *testing.T) {
@@ -2982,12 +3002,12 @@ func Test_Ctx_RenderWithOverwrittenBind(t *testing.T) {
 	err = c.Render("./.github/testdata/index.tmpl", Map{
 		"Title": "Hello from Fiber!",
 	})
+	utils.AssertEqual(t, nil, err)
 
 	buf := bytebufferpool.Get()
-	_, _ = buf.WriteString("overwrite")
+	_, _ = buf.WriteString("overwrite") //nolint:errcheck // This will never fail
 	defer bytebufferpool.Put(buf)
 
-	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "<h1>Hello from Fiber!</h1>", string(c.Response().Body()))
 }
 
@@ -3005,13 +3025,12 @@ func Test_Ctx_RenderWithBindLocals(t *testing.T) {
 	utils.AssertEqual(t, nil, err)
 
 	c.Locals("Summary", "Test")
-
 	defer app.ReleaseCtx(c)
+
 	err = c.Render("./.github/testdata/template.tmpl", Map{})
-
 	utils.AssertEqual(t, nil, err)
-	utils.AssertEqual(t, "<h1>Hello, World! Test</h1>", string(c.Response().Body()))
 
+	utils.AssertEqual(t, "<h1>Hello, World! Test</h1>", string(c.Response().Body()))
 }
 
 func Test_Ctx_RenderWithLocalsAndBinding(t *testing.T) {
@@ -3027,11 +3046,12 @@ func Test_Ctx_RenderWithLocalsAndBinding(t *testing.T) {
 
 	c.Locals("Title", "This is a test.")
 	defer app.ReleaseCtx(c)
+
 	err = c.Render("index.tmpl", Map{
 		"Title": "Hello, World!",
 	})
-
 	utils.AssertEqual(t, nil, err)
+
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(c.Response().Body()))
 }
 
@@ -3060,8 +3080,8 @@ func Benchmark_Ctx_RenderWithLocalsAndBinding(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		err = c.Render("template.tmpl", Map{})
 	}
-
 	utils.AssertEqual(b, nil, err)
+
 	utils.AssertEqual(b, "<h1>Hello, World! Test</h1>", string(c.Response().Body()))
 }
 
@@ -3083,8 +3103,8 @@ func Benchmark_Ctx_RedirectToRoute(b *testing.B) {
 			"name": "fiber",
 		})
 	}
-
 	utils.AssertEqual(b, nil, err)
+
 	utils.AssertEqual(b, 302, c.Response().StatusCode())
 	utils.AssertEqual(b, "/user/fiber", string(c.Response().Header.Peek(HeaderLocation)))
 }
@@ -3108,8 +3128,8 @@ func Benchmark_Ctx_RedirectToRouteWithQueries(b *testing.B) {
 			"queries": map[string]string{"a": "a", "b": "b"},
 		})
 	}
-
 	utils.AssertEqual(b, nil, err)
+
 	utils.AssertEqual(b, 302, c.Response().StatusCode())
 	// analysis of query parameters with url parsing, since a map pass is always randomly ordered
 	location, err := url.Parse(string(c.Response().Header.Peek(HeaderLocation)))
@@ -3138,8 +3158,8 @@ func Benchmark_Ctx_RenderLocals(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		err = c.Render("index.tmpl", Map{})
 	}
-
 	utils.AssertEqual(b, nil, err)
+
 	utils.AssertEqual(b, "<h1>Hello, World!</h1>", string(c.Response().Body()))
 }
 
@@ -3164,8 +3184,8 @@ func Benchmark_Ctx_RenderBind(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		err = c.Render("index.tmpl", Map{})
 	}
-
 	utils.AssertEqual(b, nil, err)
+
 	utils.AssertEqual(b, "<h1>Hello, World!</h1>", string(c.Response().Body()))
 }
 
@@ -3191,8 +3211,7 @@ func Test_Ctx_RestartRouting(t *testing.T) {
 func Test_Ctx_RestartRoutingWithChangedPath(t *testing.T) {
 	t.Parallel()
 	app := New()
-	executedOldHandler := false
-	executedNewHandler := false
+	var executedOldHandler, executedNewHandler bool
 
 	app.Get("/old", func(c *Ctx) error {
 		c.Path("/new")
@@ -3242,10 +3261,18 @@ type testTemplateEngine struct {
 
 func (t *testTemplateEngine) Render(w io.Writer, name string, bind interface{}, layout ...string) error {
 	if len(layout) == 0 {
-		return t.templates.ExecuteTemplate(w, name, bind)
+		if err := t.templates.ExecuteTemplate(w, name, bind); err != nil {
+			return fmt.Errorf("failed to execute template without layout: %w", err)
+		}
+		return nil
 	}
-	_ = t.templates.ExecuteTemplate(w, name, bind)
-	return t.templates.ExecuteTemplate(w, layout[0], bind)
+	if err := t.templates.ExecuteTemplate(w, name, bind); err != nil {
+		return fmt.Errorf("failed to execute template: %w", err)
+	}
+	if err := t.templates.ExecuteTemplate(w, layout[0], bind); err != nil {
+		return fmt.Errorf("failed to execute template with layout: %w", err)
+	}
+	return nil
 }
 
 func (t *testTemplateEngine) Load() error {
@@ -3324,7 +3351,6 @@ func Benchmark_Ctx_Get_Location_From_Route(b *testing.B) {
 	}
 	utils.AssertEqual(b, "/user/fiber", location)
 	utils.AssertEqual(b, nil, err)
-
 }
 
 // go test -run Test_Ctx_Get_Location_From_Route_name
@@ -3407,11 +3433,11 @@ func Test_Ctx_Get_Location_From_Route_name_Optional_greedy_one_param(t *testing.
 
 type errorTemplateEngine struct{}
 
-func (t errorTemplateEngine) Render(w io.Writer, name string, bind interface{}, layout ...string) error {
+func (errorTemplateEngine) Render(_ io.Writer, _ string, _ interface{}, _ ...string) error {
 	return errors.New("errorTemplateEngine")
 }
 
-func (t errorTemplateEngine) Load() error { return nil }
+func (errorTemplateEngine) Load() error { return nil }
 
 // go test -run Test_Ctx_Render_Engine_Error
 func Test_Ctx_Render_Engine_Error(t *testing.T) {
@@ -3429,7 +3455,10 @@ func Test_Ctx_Render_Go_Template(t *testing.T) {
 	t.Parallel()
 	file, err := os.CreateTemp(os.TempDir(), "fiber")
 	utils.AssertEqual(t, nil, err)
-	defer os.Remove(file.Name())
+	defer func() {
+		err := os.Remove(file.Name())
+		utils.AssertEqual(t, nil, err)
+	}()
 
 	_, err = file.Write([]byte("template"))
 	utils.AssertEqual(t, nil, err)
@@ -3821,7 +3850,7 @@ func Test_Ctx_QueryParser(t *testing.T) {
 	}
 	rq := new(RequiredQuery)
 	c.Request().URI().SetQueryString("")
-	utils.AssertEqual(t, "name is empty", c.QueryParser(rq).Error())
+	utils.AssertEqual(t, "failed to decode: name is empty", c.QueryParser(rq).Error())
 
 	type ArrayQuery struct {
 		Data []string
@@ -3837,7 +3866,7 @@ func Test_Ctx_QueryParser_WithSetParserDecoder(t *testing.T) {
 	t.Parallel()
 	type NonRFCTime time.Time
 
-	NonRFCConverter := func(value string) reflect.Value {
+	nonRFCConverter := func(value string) reflect.Value {
 		if v, err := time.Parse("2006-01-02", value); err == nil {
 			return reflect.ValueOf(v)
 		}
@@ -3846,7 +3875,7 @@ func Test_Ctx_QueryParser_WithSetParserDecoder(t *testing.T) {
 
 	nonRFCTime := ParserType{
 		Customtype: NonRFCTime{},
-		Converter:  NonRFCConverter,
+		Converter:  nonRFCConverter,
 	}
 
 	SetParserDecoder(ParserConfig{
@@ -3872,7 +3901,6 @@ func Test_Ctx_QueryParser_WithSetParserDecoder(t *testing.T) {
 
 	c.Request().URI().SetQueryString("date=2021-04-10&title=CustomDateTest&Body=October")
 	utils.AssertEqual(t, nil, c.QueryParser(q))
-	fmt.Println(q.Date, "q.Date")
 	utils.AssertEqual(t, "CustomDateTest", q.Title)
 	date := fmt.Sprintf("%v", q.Date)
 	utils.AssertEqual(t, "{0 63753609600 <nil>}", date)
@@ -3907,7 +3935,7 @@ func Test_Ctx_QueryParser_Schema(t *testing.T) {
 
 	c.Request().URI().SetQueryString("namex=tom&nested.age=10")
 	q = new(Query1)
-	utils.AssertEqual(t, "name is empty", c.QueryParser(q).Error())
+	utils.AssertEqual(t, "failed to decode: name is empty", c.QueryParser(q).Error())
 
 	c.Request().URI().SetQueryString("name=tom&nested.agex=10")
 	q = new(Query1)
@@ -3915,7 +3943,7 @@ func Test_Ctx_QueryParser_Schema(t *testing.T) {
 
 	c.Request().URI().SetQueryString("name=tom&test.age=10")
 	q = new(Query1)
-	utils.AssertEqual(t, "nested is empty", c.QueryParser(q).Error())
+	utils.AssertEqual(t, "failed to decode: nested is empty", c.QueryParser(q).Error())
 
 	type Query2 struct {
 		Name   string `query:"name"`
@@ -3933,11 +3961,11 @@ func Test_Ctx_QueryParser_Schema(t *testing.T) {
 
 	c.Request().URI().SetQueryString("nested.agex=10")
 	q2 = new(Query2)
-	utils.AssertEqual(t, "nested.age is empty", c.QueryParser(q2).Error())
+	utils.AssertEqual(t, "failed to decode: nested.age is empty", c.QueryParser(q2).Error())
 
 	c.Request().URI().SetQueryString("nested.agex=10")
 	q2 = new(Query2)
-	utils.AssertEqual(t, "nested.age is empty", c.QueryParser(q2).Error())
+	utils.AssertEqual(t, "failed to decode: nested.age is empty", c.QueryParser(q2).Error())
 
 	type Node struct {
 		Value int   `query:"val,required"`
@@ -3951,7 +3979,7 @@ func Test_Ctx_QueryParser_Schema(t *testing.T) {
 
 	c.Request().URI().SetQueryString("next.val=2")
 	n = new(Node)
-	utils.AssertEqual(t, "val is empty", c.QueryParser(n).Error())
+	utils.AssertEqual(t, "failed to decode: val is empty", c.QueryParser(n).Error())
 
 	c.Request().URI().SetQueryString("val=3&next.value=2")
 	n = new(Node)
@@ -4057,7 +4085,7 @@ func Test_Ctx_ReqHeaderParser(t *testing.T) {
 	}
 	rh := new(RequiredHeader)
 	c.Request().Header.Del("name")
-	utils.AssertEqual(t, "name is empty", c.ReqHeaderParser(rh).Error())
+	utils.AssertEqual(t, "failed to decode: name is empty", c.ReqHeaderParser(rh).Error())
 }
 
 // go test -run Test_Ctx_ReqHeaderParser_WithSetParserDecoder -v
@@ -4065,7 +4093,7 @@ func Test_Ctx_ReqHeaderParser_WithSetParserDecoder(t *testing.T) {
 	t.Parallel()
 	type NonRFCTime time.Time
 
-	NonRFCConverter := func(value string) reflect.Value {
+	nonRFCConverter := func(value string) reflect.Value {
 		if v, err := time.Parse("2006-01-02", value); err == nil {
 			return reflect.ValueOf(v)
 		}
@@ -4074,7 +4102,7 @@ func Test_Ctx_ReqHeaderParser_WithSetParserDecoder(t *testing.T) {
 
 	nonRFCTime := ParserType{
 		Customtype: NonRFCTime{},
-		Converter:  NonRFCConverter,
+		Converter:  nonRFCConverter,
 	}
 
 	SetParserDecoder(ParserConfig{
@@ -4103,7 +4131,6 @@ func Test_Ctx_ReqHeaderParser_WithSetParserDecoder(t *testing.T) {
 	c.Request().Header.Add("Body", "October")
 
 	utils.AssertEqual(t, nil, c.ReqHeaderParser(r))
-	fmt.Println(r.Date, "q.Date")
 	utils.AssertEqual(t, "CustomDateTest", r.Title)
 	date := fmt.Sprintf("%v", r.Date)
 	utils.AssertEqual(t, "{0 63753609600 <nil>}", date)
@@ -4140,7 +4167,7 @@ func Test_Ctx_ReqHeaderParser_Schema(t *testing.T) {
 
 	c.Request().Header.Del("Name")
 	q = new(Header1)
-	utils.AssertEqual(t, "Name is empty", c.ReqHeaderParser(q).Error())
+	utils.AssertEqual(t, "failed to decode: Name is empty", c.ReqHeaderParser(q).Error())
 
 	c.Request().Header.Add("Name", "tom")
 	c.Request().Header.Del("Nested.Age")
@@ -4150,7 +4177,7 @@ func Test_Ctx_ReqHeaderParser_Schema(t *testing.T) {
 
 	c.Request().Header.Del("Nested.Agex")
 	q = new(Header1)
-	utils.AssertEqual(t, "Nested is empty", c.ReqHeaderParser(q).Error())
+	utils.AssertEqual(t, "failed to decode: Nested is empty", c.ReqHeaderParser(q).Error())
 
 	c.Request().Header.Del("Nested.Agex")
 	c.Request().Header.Del("Name")
@@ -4176,7 +4203,7 @@ func Test_Ctx_ReqHeaderParser_Schema(t *testing.T) {
 	c.Request().Header.Del("Nested.Age")
 	c.Request().Header.Add("Nested.Agex", "10")
 	h2 = new(Header2)
-	utils.AssertEqual(t, "Nested.age is empty", c.ReqHeaderParser(h2).Error())
+	utils.AssertEqual(t, "failed to decode: Nested.age is empty", c.ReqHeaderParser(h2).Error())
 
 	type Node struct {
 		Value int   `reqHeader:"Val,required"`
@@ -4191,7 +4218,7 @@ func Test_Ctx_ReqHeaderParser_Schema(t *testing.T) {
 
 	c.Request().Header.Del("Val")
 	n = new(Node)
-	utils.AssertEqual(t, "Val is empty", c.ReqHeaderParser(n).Error())
+	utils.AssertEqual(t, "failed to decode: Val is empty", c.ReqHeaderParser(n).Error())
 
 	c.Request().Header.Add("Val", "3")
 	c.Request().Header.Del("Next.Val")
@@ -4628,8 +4655,9 @@ func Test_Ctx_RepeatParserWithSameStruct(t *testing.T) {
 
 	var gzipJSON bytes.Buffer
 	w := gzip.NewWriter(&gzipJSON)
-	_, _ = w.Write([]byte(`{"body_param":"body_param"}`))
-	_ = w.Close()
+	_, _ = w.Write([]byte(`{"body_param":"body_param"}`)) //nolint:errcheck // This will never fail
+	err := w.Close()
+	utils.AssertEqual(t, nil, err)
 	c.Request().Header.SetContentType(MIMEApplicationJSON)
 	c.Request().Header.Set(HeaderContentEncoding, "gzip")
 	c.Request().SetBody(gzipJSON.Bytes())

error_test.go

@@ -1,11 +1,10 @@
 package fiber
 
 import (
+	"encoding/json"
 	"errors"
 	"testing"
 
-	jerrors "encoding/json"
-
 	"github.com/gofiber/fiber/v2/internal/schema"
 	"github.com/gofiber/fiber/v2/utils"
 )
@@ -36,42 +35,42 @@ func TestMultiError(t *testing.T) {
 
 func TestInvalidUnmarshalError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.InvalidUnmarshalError
+	var e *json.InvalidUnmarshalError
 	ok := errors.As(&InvalidUnmarshalError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }
 
 func TestMarshalerError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.MarshalerError
+	var e *json.MarshalerError
 	ok := errors.As(&MarshalerError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }
 
 func TestSyntaxError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.SyntaxError
+	var e *json.SyntaxError
 	ok := errors.As(&SyntaxError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }
 
 func TestUnmarshalTypeError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.UnmarshalTypeError
+	var e *json.UnmarshalTypeError
 	ok := errors.As(&UnmarshalTypeError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }
 
 func TestUnsupportedTypeError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.UnsupportedTypeError
+	var e *json.UnsupportedTypeError
 	ok := errors.As(&UnsupportedTypeError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }
 
 func TestUnsupportedValeError(t *testing.T) {
 	t.Parallel()
-	var e *jerrors.UnsupportedValueError
+	var e *json.UnsupportedValueError
 	ok := errors.As(&UnsupportedValueError{}, &e)
 	utils.AssertEqual(t, true, ok)
 }

group.go

@@ -168,7 +168,6 @@ func (grp *Group) Group(prefix string, handlers ...Handler) Router {
 	}
 
 	return newGrp
-
 }
 
 // Route is used to define routes with a common prefix inside the common function.

helpers.go

@@ -20,13 +20,13 @@ import (
 	"unsafe"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/bytebufferpool"
 	"github.com/valyala/fasthttp"
 )
 
-/* #nosec */
-// getTlsConfig returns a net listener's tls config
-func getTlsConfig(ln net.Listener) *tls.Config {
+// getTLSConfig returns a net listener's tls config
+func getTLSConfig(ln net.Listener) *tls.Config {
 	// Get listener type
 	pointer := reflect.ValueOf(ln)
 
@@ -37,12 +37,16 @@ func getTlsConfig(ln net.Listener) *tls.Config {
 			// Get private field from value
 			if field := val.FieldByName("config"); field.Type() != nil {
 				// Copy value from pointer field (unsafe)
-				newval := reflect.NewAt(field.Type(), unsafe.Pointer(field.UnsafeAddr())) // #nosec G103
+				newval := reflect.NewAt(field.Type(), unsafe.Pointer(field.UnsafeAddr())) //nolint:gosec // Probably the only way to extract the *tls.Config from a net.Listener. TODO: Verify there really is no easier way without using unsafe.
 				if newval.Type() != nil {
 					// Get element from pointer
 					if elem := newval.Elem(); elem.Type() != nil {
 						// Cast value to *tls.Config
-						return elem.Interface().(*tls.Config)
+						c, ok := elem.Interface().(*tls.Config)
+						if !ok {
+							panic(fmt.Errorf("failed to type-assert to *tls.Config"))
+						}
+						return c
 					}
 				}
 			}
@@ -53,19 +57,21 @@ func getTlsConfig(ln net.Listener) *tls.Config {
 }
 
 // readContent opens a named file and read content from it
-func readContent(rf io.ReaderFrom, name string) (n int64, err error) {
+func readContent(rf io.ReaderFrom, name string) (int64, error) {
 	// Read file
 	f, err := os.Open(filepath.Clean(name))
 	if err != nil {
-		return 0, err
+		return 0, fmt.Errorf("failed to open: %w", err)
 	}
-	// #nosec G307
 	defer func() {
 		if err = f.Close(); err != nil {
 			log.Printf("Error closing file: %s\n", err)
 		}
 	}()
-	return rf.ReadFrom(f)
+	if n, err := rf.ReadFrom(f); err != nil {
+		return n, fmt.Errorf("failed to read: %w", err)
+	}
+	return 0, nil
 }
 
 // quoteString escape special characters in a given string
@@ -78,7 +84,8 @@ func (app *App) quoteString(raw string) string {
 }
 
 // Scan stack if other methods match the request
-func (app *App) methodExist(ctx *Ctx) (exist bool) {
+func (app *App) methodExist(ctx *Ctx) bool {
+	var exists bool
 	methods := app.config.RequestMethods
 	for i := 0; i < len(methods); i++ {
 		// Skip original method
@@ -108,7 +115,7 @@ func (app *App) methodExist(ctx *Ctx) (exist bool) {
 			// No match, next route
 			if match {
 				// We matched
-				exist = true
+				exists = true
 				// Add method to Allow header
 				ctx.Append(HeaderAllow, methods[i])
 				// Break stack loop
@@ -116,7 +123,7 @@ func (app *App) methodExist(ctx *Ctx) (exist bool) {
 			}
 		}
 	}
-	return
+	return exists
 }
 
 // uniqueRouteStack drop all not unique routes from the slice
@@ -146,7 +153,7 @@ func defaultString(value string, defaultValue []string) string {
 const normalizedHeaderETag = "Etag"
 
 // Generate and set ETag header to response
-func setETag(c *Ctx, weak bool) {
+func setETag(c *Ctx, weak bool) { //nolint: revive // Accepting a bool param is fine here
 	// Don't generate ETags for invalid responses
 	if c.fasthttp.Response.StatusCode() != StatusOK {
 		return
@@ -160,7 +167,8 @@ func setETag(c *Ctx, weak bool) {
 	clientEtag := c.Get(HeaderIfNoneMatch)
 
 	// Generate ETag for response
-	crc32q := crc32.MakeTable(0xD5828281)
+	const pol = 0xD5828281
+	crc32q := crc32.MakeTable(pol)
 	etag := fmt.Sprintf("\"%d-%v\"", len(body), crc32.Checksum(body, crc32q))
 
 	// Enable weak tag
@@ -173,7 +181,9 @@ func setETag(c *Ctx, weak bool) {
 		// Check if server's ETag is weak
 		if clientEtag[2:] == etag || clientEtag[2:] == etag[2:] {
 			// W/1 == 1 || W/1 == W/1
-			_ = c.SendStatus(StatusNotModified)
+			if err := c.SendStatus(StatusNotModified); err != nil {
+				log.Printf("setETag: failed to SendStatus: %v\n", err)
+			}
 			c.fasthttp.ResetBody()
 			return
 		}
@@ -183,7 +193,9 @@ func setETag(c *Ctx, weak bool) {
 	}
 	if strings.Contains(clientEtag, etag) {
 		// 1 == 1
-		_ = c.SendStatus(StatusNotModified)
+		if err := c.SendStatus(StatusNotModified); err != nil {
+			log.Printf("setETag: failed to SendStatus: %v\n", err)
+		}
 		c.fasthttp.ResetBody()
 		return
 	}
@@ -239,7 +251,7 @@ func getOffer(header string, offers ...string) string {
 	return ""
 }
 
-func matchEtag(s string, etag string) bool {
+func matchEtag(s, etag string) bool {
 	if s == etag || s == "W/"+etag || "W/"+s == etag {
 		return true
 	}
@@ -254,12 +266,12 @@ func (app *App) isEtagStale(etag string, noneMatchBytes []byte) bool {
 	// https://github.com/jshttp/fresh/blob/10e0471669dbbfbfd8de65bc6efac2ddd0bfa057/index.js#L110
 	for i := range noneMatchBytes {
 		switch noneMatchBytes[i] {
-		case 0x20:
+		case 0x20: //nolint:gomnd // This is a space (" ")
 			if start == end {
 				start = i + 1
 				end = i + 1
 			}
-		case 0x2c:
+		case 0x2c: //nolint:gomnd // This is a comma (",")
 			if matchEtag(app.getString(noneMatchBytes[start:end]), etag) {
 				return false
 			}
@@ -273,7 +285,7 @@ func (app *App) isEtagStale(etag string, noneMatchBytes []byte) bool {
 	return !matchEtag(app.getString(noneMatchBytes[start:end]), etag)
 }
 
-func parseAddr(raw string) (host, port string) {
+func parseAddr(raw string) (string, string) { //nolint:revive // Returns (host, port)
 	if i := strings.LastIndex(raw, ":"); i != -1 {
 		return raw[:i], raw[i+1:]
 	}
@@ -313,21 +325,21 @@ type testConn struct {
 	w bytes.Buffer
 }
 
-func (c *testConn) Read(b []byte) (int, error)  { return c.r.Read(b) }
-func (c *testConn) Write(b []byte) (int, error) { return c.w.Write(b) }
-func (c *testConn) Close() error                { return nil }
+func (c *testConn) Read(b []byte) (int, error)  { return c.r.Read(b) }  //nolint:wrapcheck // This must not be wrapped
+func (c *testConn) Write(b []byte) (int, error) { return c.w.Write(b) } //nolint:wrapcheck // This must not be wrapped
+func (*testConn) Close() error                  { return nil }
 
-func (c *testConn) LocalAddr() net.Addr                { return &net.TCPAddr{Port: 0, Zone: "", IP: net.IPv4zero} }
-func (c *testConn) RemoteAddr() net.Addr               { return &net.TCPAddr{Port: 0, Zone: "", IP: net.IPv4zero} }
-func (c *testConn) SetDeadline(_ time.Time) error      { return nil }
-func (c *testConn) SetReadDeadline(_ time.Time) error  { return nil }
-func (c *testConn) SetWriteDeadline(_ time.Time) error { return nil }
+func (*testConn) LocalAddr() net.Addr                { return &net.TCPAddr{Port: 0, Zone: "", IP: net.IPv4zero} }
+func (*testConn) RemoteAddr() net.Addr               { return &net.TCPAddr{Port: 0, Zone: "", IP: net.IPv4zero} }
+func (*testConn) SetDeadline(_ time.Time) error      { return nil }
+func (*testConn) SetReadDeadline(_ time.Time) error  { return nil }
+func (*testConn) SetWriteDeadline(_ time.Time) error { return nil }
 
-var getStringImmutable = func(b []byte) string {
+func getStringImmutable(b []byte) string {
 	return string(b)
 }
 
-var getBytesImmutable = func(s string) (b []byte) {
+func getBytesImmutable(s string) []byte {
 	return []byte(s)
 }
 
@@ -335,6 +347,7 @@ var getBytesImmutable = func(s string) (b []byte) {
 func (app *App) methodInt(s string) int {
 	// For better performance
 	if len(app.configured.RequestMethods) == 0 {
+		//nolint:gomnd // TODO: Use iota instead
 		switch s {
 		case MethodGet:
 			return 0
@@ -391,8 +404,7 @@ func IsMethodIdempotent(m string) bool {
 	}
 
 	switch m {
-	case MethodPut,
-		MethodDelete:
+	case MethodPut, MethodDelete:
 		return true
 	default:
 		return false
@@ -714,7 +726,7 @@ const (
 	ConstraintBool            = "bool"
 	ConstraintFloat           = "float"
 	ConstraintAlpha           = "alpha"
-	ConstraintGuid            = "guid"
+	ConstraintGuid            = "guid" //nolint:revive,stylecheck // TODO: Rename to "ConstraintGUID" in v3
 	ConstraintMinLen          = "minLen"
 	ConstraintMaxLen          = "maxLen"
 	ConstraintLen             = "len"

helpers_test.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 

hooks.go

@@ -1,14 +1,20 @@
 package fiber
 
+import (
+	"log"
+)
+
 // OnRouteHandler Handlers define a function to create hooks for Fiber.
-type OnRouteHandler = func(Route) error
-type OnNameHandler = OnRouteHandler
-type OnGroupHandler = func(Group) error
-type OnGroupNameHandler = OnGroupHandler
-type OnListenHandler = func() error
-type OnShutdownHandler = OnListenHandler
-type OnForkHandler = func(int) error
-type OnMountHandler = func(*App) error
+type (
+	OnRouteHandler     = func(Route) error
+	OnNameHandler      = OnRouteHandler
+	OnGroupHandler     = func(Group) error
+	OnGroupNameHandler = OnGroupHandler
+	OnListenHandler    = func() error
+	OnShutdownHandler  = OnListenHandler
+	OnForkHandler      = func(int) error
+	OnMountHandler     = func(*App) error
+)
 
 // Hooks is a struct to use it with App.
 type Hooks struct {
@@ -180,13 +186,17 @@ func (h *Hooks) executeOnListenHooks() error {
 
 func (h *Hooks) executeOnShutdownHooks() {
 	for _, v := range h.onShutdown {
-		_ = v()
+		if err := v(); err != nil {
+			log.Printf("failed to call shutdown hook: %v\n", err)
+		}
 	}
 }
 
 func (h *Hooks) executeOnForkHooks(pid int) {
 	for _, v := range h.onFork {
-		_ = v(pid)
+		if err := v(pid); err != nil {
+			log.Printf("failed to call fork hook: %v\n", err)
+		}
 	}
 }
 

hooks_test.go

@@ -7,10 +7,11 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/bytebufferpool"
 )
 
-var testSimpleHandler = func(c *Ctx) error {
+func testSimpleHandler(c *Ctx) error {
 	return c.SendString("simple")
 }
 

internal/dictpool/pool.go

@@ -10,7 +10,7 @@ var defaultPool = sync.Pool{
 
 // AcquireDict acquire new dict.
 func AcquireDict() *Dict {
-	return defaultPool.Get().(*Dict) // nolint:forcetypeassert
+	return defaultPool.Get().(*Dict)
 }
 
 // ReleaseDict release dict.

internal/gopsutil/common/common.go

@@ -366,7 +366,7 @@ func HostDev(combineWith ...string) string {
 // getSysctrlEnv sets LC_ALL=C in a list of env vars for use when running
 // sysctl commands (see DoSysctrl).
 func getSysctrlEnv(env []string) []string {
-	foundLC := false
+	var foundLC bool
 	for i, line := range env {
 		if strings.HasPrefix(line, "LC_ALL") {
 			env[i] = "LC_ALL=C"

internal/gopsutil/mem/mem.go

@@ -6,8 +6,7 @@ import (
 	"github.com/gofiber/fiber/v2/internal/gopsutil/common"
 )
 
-//lint:ignore U1000 we need this elsewhere
-var invoke common.Invoker = common.Invoke{} //nolint:all
+var invoke common.Invoker = common.Invoke{} //nolint:unused // We use this only for some OS'es
 
 // Memory usage statistics. Total, Available and Used contain numbers of bytes
 // for human consumption.

internal/gopsutil/mem/mem_freebsd.go

@@ -86,7 +86,6 @@ func SwapMemory() (*SwapMemoryStat, error) {
 }
 
 // Constants from vm/vm_param.h
-// nolint: golint
 const (
 	XSWDEV_VERSION11 = 1
 	XSWDEV_VERSION   = 2

internal/gopsutil/mem/mem_linux.go

@@ -57,10 +57,12 @@ func fillFromMeminfoWithContext(ctx context.Context) (*VirtualMemoryStat, *Virtu
 	lines, _ := common.ReadLines(filename)
 
 	// flag if MemAvailable is in /proc/meminfo (kernel 3.14+)
-	memavail := false
-	activeFile := false   // "Active(file)" not available: 2.6.28 / Dec 2008
-	inactiveFile := false // "Inactive(file)" not available: 2.6.28 / Dec 2008
-	sReclaimable := false // "SReclaimable:" not available: 2.6.19 / Nov 2006
+	var (
+		memavail     bool
+		activeFile   bool // "Active(file)" not available: 2.6.28 / Dec 2008
+		inactiveFile bool // "Inactive(file)" not available: 2.6.28 / Dec 2008
+		sReclaimable bool // "SReclaimable:" not available: 2.6.19 / Nov 2006
+	)
 
 	ret := &VirtualMemoryStat{}
 	retEx := &VirtualMemoryExStat{}

internal/msgp/json.go

@@ -168,7 +168,7 @@ func rwArray(dst jsWriter, src *Reader) (n int, err error) {
 	if err != nil {
 		return
 	}
-	comma := false
+	var comma bool
 	for i := uint32(0); i < sz; i++ {
 		if comma {
 			err = dst.WriteByte(',')

internal/schema/cache.go

@@ -163,7 +163,7 @@ func (c *cache) createField(field reflect.StructField, parentAlias string) *fiel
 	}
 	// Check if the type is supported and don't cache it if not.
 	// First let's get the basic type.
-	isSlice, isStruct := false, false
+	var isSlice, isStruct bool
 	ft := field.Type
 	m := isTextUnmarshaler(reflect.Zero(ft))
 	if ft.Kind() == reflect.Ptr {

internal/storage/memory/memory_test.go

@@ -149,13 +149,13 @@ func Benchmark_Storage_Memory(b *testing.B) {
 		b.ResetTimer()
 		for n := 0; n < b.N; n++ {
 			for _, key := range keys {
-				d.Set(key, value, ttl)
+				_ = d.Set(key, value, ttl)
 			}
 			for _, key := range keys {
 				_, _ = d.Get(key)
 			}
 			for _, key := range keys {
-				d.Delete(key)
+				_ = d.Delete(key)
 			}
 		}
 	})

internal/template/html/html.go

@@ -156,7 +156,6 @@ func (e *Engine) Load() error {
 		name = strings.TrimSuffix(name, e.extension)
 		// name = strings.Replace(name, e.extension, "", -1)
 		// Read the file
-		// #gosec G304
 		buf, err := utils.ReadFile(path, e.fileSystem)
 		if err != nil {
 			return err

internal/template/utils/utils.go

@@ -21,7 +21,6 @@ func Walk(fs http.FileSystem, root string, walkFn filepath.WalkFunc) error {
 	return walk(fs, root, info, walkFn)
 }
 
-// #nosec G304
 // ReadFile returns the raw content of a file
 func ReadFile(path string, fs http.FileSystem) ([]byte, error) {
 	if fs != nil {

listen.go

@@ -9,6 +9,7 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
+	"log"
 	"net"
 	"os"
 	"path/filepath"
@@ -31,7 +32,7 @@ func (app *App) Listener(ln net.Listener) error {
 
 	// Print startup message
 	if !app.config.DisableStartupMessage {
-		app.startupMessage(ln.Addr().String(), getTlsConfig(ln) != nil, "")
+		app.startupMessage(ln.Addr().String(), getTLSConfig(ln) != nil, "")
 	}
 
 	// Print routes
@@ -41,7 +42,7 @@ func (app *App) Listener(ln net.Listener) error {
 
 	// Prefork is not supported for custom listeners
 	if app.config.Prefork {
-		fmt.Println("[Warning] Prefork isn't supported for custom listeners.")
+		log.Printf("[Warning] Prefork isn't supported for custom listeners.\n")
 	}
 
 	// Start listening
@@ -61,7 +62,7 @@ func (app *App) Listen(addr string) error {
 	// Setup listener
 	ln, err := net.Listen(app.config.Network, addr)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to listen: %w", err)
 	}
 
 	// prepare the server for the start
@@ -94,7 +95,7 @@ func (app *App) ListenTLS(addr, certFile, keyFile string) error {
 	// Set TLS config with handler
 	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
 	if err != nil {
-		return fmt.Errorf("tls: cannot load TLS key pair from certFile=%q and keyFile=%q: %s", certFile, keyFile, err)
+		return fmt.Errorf("tls: cannot load TLS key pair from certFile=%q and keyFile=%q: %w", certFile, keyFile, err)
 	}
 
 	tlsHandler := &TLSHandler{}
@@ -115,7 +116,7 @@ func (app *App) ListenTLS(addr, certFile, keyFile string) error {
 	ln, err := net.Listen(app.config.Network, addr)
 	ln = tls.NewListener(ln, config)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to listen: %w", err)
 	}
 
 	// prepare the server for the start
@@ -150,12 +151,12 @@ func (app *App) ListenMutualTLS(addr, certFile, keyFile, clientCertFile string)
 
 	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
 	if err != nil {
-		return fmt.Errorf("tls: cannot load TLS key pair from certFile=%q and keyFile=%q: %s", certFile, keyFile, err)
+		return fmt.Errorf("tls: cannot load TLS key pair from certFile=%q and keyFile=%q: %w", certFile, keyFile, err)
 	}
 
 	clientCACert, err := os.ReadFile(filepath.Clean(clientCertFile))
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to read file: %w", err)
 	}
 	clientCertPool := x509.NewCertPool()
 	clientCertPool.AppendCertsFromPEM(clientCACert)
@@ -179,7 +180,7 @@ func (app *App) ListenMutualTLS(addr, certFile, keyFile, clientCertFile string)
 	// Setup listener
 	ln, err := tls.Listen(app.config.Network, addr, config)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to listen: %w", err)
 	}
 
 	// prepare the server for the start
@@ -203,7 +204,7 @@ func (app *App) ListenMutualTLS(addr, certFile, keyFile, clientCertFile string)
 }
 
 // startupMessage prepares the startup message with the handler number, port, address and other information
-func (app *App) startupMessage(addr string, tls bool, pids string) {
+func (app *App) startupMessage(addr string, tls bool, pids string) { //nolint: revive // Accepting a bool param is fine here
 	// ignore child processes
 	if IsChild() {
 		return
@@ -227,7 +228,8 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 	}
 
 	center := func(s string, width int) string {
-		pad := strconv.Itoa((width - len(s)) / 2)
+		const padDiv = 2
+		pad := strconv.Itoa((width - len(s)) / padDiv)
 		str := fmt.Sprintf("%"+pad+"s", " ")
 		str += s
 		str += fmt.Sprintf("%"+pad+"s", " ")
@@ -238,7 +240,8 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 	}
 
 	centerValue := func(s string, width int) string {
-		pad := strconv.Itoa((width - runewidth.StringWidth(s)) / 2)
+		const padDiv = 2
+		pad := strconv.Itoa((width - runewidth.StringWidth(s)) / padDiv)
 		str := fmt.Sprintf("%"+pad+"s", " ")
 		str += fmt.Sprintf("%s%s%s", colors.Cyan, s, colors.Black)
 		str += fmt.Sprintf("%"+pad+"s", " ")
@@ -249,13 +252,13 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 		return str
 	}
 
-	pad := func(s string, width int) (str string) {
+	pad := func(s string, width int) string {
 		toAdd := width - len(s)
-		str += s
+		str := s
 		for i := 0; i < toAdd; i++ {
 			str += " "
 		}
-		return
+		return str
 	}
 
 	host, port := parseAddr(addr)
@@ -267,9 +270,9 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 		}
 	}
 
-	scheme := "http"
+	scheme := schemeHTTP
 	if tls {
-		scheme = "https"
+		scheme = schemeHTTPS
 	}
 
 	isPrefork := "Disabled"
@@ -282,19 +285,18 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 		procs = "1"
 	}
 
+	const lineLen = 49
 	mainLogo := colors.Black + " ┌───────────────────────────────────────────────────┐\n"
 	if app.config.AppName != "" {
-		mainLogo += " │ " + centerValue(app.config.AppName, 49) + " │\n"
+		mainLogo += " │ " + centerValue(app.config.AppName, lineLen) + " │\n"
 	}
-	mainLogo += " │ " + centerValue("Fiber v"+Version, 49) + " │\n"
+	mainLogo += " │ " + centerValue("Fiber v"+Version, lineLen) + " │\n"
 
 	if host == "0.0.0.0" {
-		mainLogo +=
-			" │ " + center(fmt.Sprintf("%s://127.0.0.1:%s", scheme, port), 49) + " │\n" +
-				" │ " + center(fmt.Sprintf("(bound on host 0.0.0.0 and port %s)", port), 49) + " │\n"
+		mainLogo += " │ " + center(fmt.Sprintf("%s://127.0.0.1:%s", scheme, port), lineLen) + " │\n" +
+			" │ " + center(fmt.Sprintf("(bound on host 0.0.0.0 and port %s)", port), lineLen) + " │\n"
 	} else {
-		mainLogo +=
-			" │ " + center(fmt.Sprintf("%s://%s:%s", scheme, host, port), 49) + " │\n"
+		mainLogo += " │ " + center(fmt.Sprintf("%s://%s:%s", scheme, host, port), lineLen) + " │\n"
 	}
 
 	mainLogo += fmt.Sprintf(
@@ -303,8 +305,8 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 			" │ Prefork .%s  PID ....%s │\n"+
 			" └───────────────────────────────────────────────────┘"+
 			colors.Reset,
-		value(strconv.Itoa(int(app.handlersCount)), 14), value(procs, 12),
-		value(isPrefork, 14), value(strconv.Itoa(os.Getpid()), 14),
+		value(strconv.Itoa(int(app.handlersCount)), 14), value(procs, 12), //nolint:gomnd // Using random padding lengths is fine here
+		value(isPrefork, 14), value(strconv.Itoa(os.Getpid()), 14), //nolint:gomnd // Using random padding lengths is fine here
 	)
 
 	var childPidsLogo string
@@ -329,19 +331,21 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 		thisLine := "Child PIDs ... "
 		var itemsOnThisLine []string
 
+		const maxLineLen = 49
+
 		addLine := func() {
 			lines = append(lines,
 				fmt.Sprintf(
 					newLine,
 					colors.Black,
-					thisLine+colors.Cyan+pad(strings.Join(itemsOnThisLine, ", "), 49-len(thisLine)),
+					thisLine+colors.Cyan+pad(strings.Join(itemsOnThisLine, ", "), maxLineLen-len(thisLine)),
 					colors.Black,
 				),
 			)
 		}
 
 		for _, pid := range pidSlice {
-			if len(thisLine+strings.Join(append(itemsOnThisLine, pid), ", ")) > 49 {
+			if len(thisLine+strings.Join(append(itemsOnThisLine, pid), ", ")) > maxLineLen {
 				addLine()
 				thisLine = ""
 				itemsOnThisLine = []string{pid}
@@ -415,7 +419,7 @@ func (app *App) printRoutesMessage() {
 	var routes []RouteMessage
 	for _, routeStack := range app.stack {
 		for _, route := range routeStack {
-			var newRoute = RouteMessage{}
+			var newRoute RouteMessage
 			newRoute.name = route.Name
 			newRoute.method = route.Method
 			newRoute.path = route.Path
@@ -443,5 +447,5 @@ func (app *App) printRoutesMessage() {
 		_, _ = fmt.Fprintf(w, "%s%s\t%s| %s%s\t%s| %s%s\t%s| %s%s\n", colors.Blue, route.method, colors.White, colors.Green, route.path, colors.White, colors.Cyan, route.name, colors.White, colors.Yellow, route.handlers)
 	}
 
-	_ = w.Flush()
+	_ = w.Flush() //nolint:errcheck // It is fine to ignore the error here
 }

listen_test.go

@@ -7,7 +7,6 @@ package fiber
 import (
 	"bytes"
 	"crypto/tls"
-	"fmt"
 	"io"
 	"log"
 	"os"
@@ -17,6 +16,7 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp/fasthttputil"
 )
 
@@ -125,8 +125,10 @@ func Test_App_Listener_TLS_Listener(t *testing.T) {
 	if err != nil {
 		utils.AssertEqual(t, nil, err)
 	}
+	//nolint:gosec // We're in a test so using old ciphers is fine
 	config := &tls.Config{Certificates: []tls.Certificate{cer}}
 
+	//nolint:gosec // We're in a test so listening on all interfaces is fine
 	ln, err := tls.Listen(NetworkTCP4, ":0", config)
 	utils.AssertEqual(t, nil, err)
 
@@ -182,7 +184,6 @@ func Test_App_Master_Process_Show_Startup_Message(t *testing.T) {
 		New(Config{Prefork: true}).
 			startupMessage(":3000", true, strings.Repeat(",11111,22222,33333,44444,55555,60000", 10))
 	})
-	fmt.Println(startupMessage)
 	utils.AssertEqual(t, true, strings.Contains(startupMessage, "https://127.0.0.1:3000"))
 	utils.AssertEqual(t, true, strings.Contains(startupMessage, "(bound on host 0.0.0.0 and port 3000)"))
 	utils.AssertEqual(t, true, strings.Contains(startupMessage, "Child PIDs"))
@@ -196,7 +197,6 @@ func Test_App_Master_Process_Show_Startup_MessageWithAppName(t *testing.T) {
 	startupMessage := captureOutput(func() {
 		app.startupMessage(":3000", true, strings.Repeat(",11111,22222,33333,44444,55555,60000", 10))
 	})
-	fmt.Println(startupMessage)
 	utils.AssertEqual(t, "Test App v1.0.1", app.Config().AppName)
 	utils.AssertEqual(t, true, strings.Contains(startupMessage, app.Config().AppName))
 }
@@ -208,7 +208,6 @@ func Test_App_Master_Process_Show_Startup_MessageWithAppNameNonAscii(t *testing.
 	startupMessage := captureOutput(func() {
 		app.startupMessage(":3000", false, "")
 	})
-	fmt.Println(startupMessage)
 	utils.AssertEqual(t, true, strings.Contains(startupMessage, "│        Serveur de vérification des données        │"))
 }
 
@@ -219,8 +218,7 @@ func Test_App_print_Route(t *testing.T) {
 	printRoutesMessage := captureOutput(func() {
 		app.printRoutesMessage()
 	})
-	fmt.Println(printRoutesMessage)
-	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "GET"))
+	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, MethodGet))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "/"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "emptyHandler"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "routeName"))
@@ -240,11 +238,11 @@ func Test_App_print_Route_with_group(t *testing.T) {
 		app.printRoutesMessage()
 	})
 
-	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "GET"))
+	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, MethodGet))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "/"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "emptyHandler"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "/v1/test"))
-	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "POST"))
+	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, MethodPost))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "/v1/test/fiber"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "PUT"))
 	utils.AssertEqual(t, true, strings.Contains(printRoutesMessage, "/v1/test/fiber/*"))

middleware/basicauth/basicauth_test.go

@@ -1,15 +1,15 @@
 package basicauth
 
 import (
+	"encoding/base64"
 	"fmt"
 	"io"
 	"net/http/httptest"
 	"testing"
 
-	b64 "encoding/base64"
-
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -23,7 +23,7 @@ func Test_BasicAuth_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -39,6 +39,7 @@ func Test_Middleware_BasicAuth(t *testing.T) {
 		},
 	}))
 
+	//nolint:forcetypeassert,errcheck // TODO: Do not force-type assert
 	app.Get("/testauth", func(c *fiber.Ctx) error {
 		username := c.Locals("username").(string)
 		password := c.Locals("password").(string)
@@ -74,9 +75,9 @@ func Test_Middleware_BasicAuth(t *testing.T) {
 
 	for _, tt := range tests {
 		// Base64 encode credentials for http auth header
-		creds := b64.StdEncoding.EncodeToString([]byte(fmt.Sprintf("%s:%s", tt.username, tt.password)))
+		creds := base64.StdEncoding.EncodeToString([]byte(fmt.Sprintf("%s:%s", tt.username, tt.password)))
 
-		req := httptest.NewRequest("GET", "/testauth", nil)
+		req := httptest.NewRequest(fiber.MethodGet, "/testauth", nil)
 		req.Header.Add("Authorization", "Basic "+creds)
 		resp, err := app.Test(req)
 		utils.AssertEqual(t, nil, err)
@@ -108,7 +109,7 @@ func Benchmark_Middleware_BasicAuth(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 	fctx.Request.Header.Set(fiber.HeaderAuthorization, "basic am9objpkb2U=") // john:doe
 

middleware/basicauth/config.go

@@ -53,6 +53,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:            nil,
 	Users:           map[string]string{},

middleware/cache/cache.go

@@ -34,6 +34,7 @@ const (
 	noStore = "no-store"
 )
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var ignoreHeaders = map[string]interface{}{
 	"Connection":          nil,
 	"Keep-Alive":          nil,
@@ -43,8 +44,8 @@ var ignoreHeaders = map[string]interface{}{
 	"Trailers":            nil,
 	"Transfer-Encoding":   nil,
 	"Upgrade":             nil,
-	"Content-Type":        nil, // already stored explicitely by the cache manager
-	"Content-Encoding":    nil, // already stored explicitely by the cache manager
+	"Content-Type":        nil, // already stored explicitly by the cache manager
+	"Content-Encoding":    nil, // already stored explicitly by the cache manager
 }
 
 // New creates a new middleware handler
@@ -69,7 +70,7 @@ func New(config ...Config) fiber.Handler {
 	// Create indexed heap for tracking expirations ( see heap.go )
 	heap := &indexedHeap{}
 	// count stored bytes (sizes of response bodies)
-	var storedBytes uint = 0
+	var storedBytes uint
 
 	// Update timestamp in the configured interval
 	go func() {
@@ -81,10 +82,10 @@ func New(config ...Config) fiber.Handler {
 
 	// Delete key from both manager and storage
 	deleteKey := func(dkey string) {
-		manager.delete(dkey)
+		manager.del(dkey)
 		// External storage saves body data with different key
 		if cfg.Storage != nil {
-			manager.delete(dkey + "_body")
+			manager.del(dkey + "_body")
 		}
 	}
 
@@ -205,7 +206,7 @@ func New(config ...Config) fiber.Handler {
 		if cfg.StoreResponseHeaders {
 			e.headers = make(map[string][]byte)
 			c.Response().Header.VisitAll(
-				func(key []byte, value []byte) {
+				func(key, value []byte) {
 					// create real copy
 					keyS := string(key)
 					if _, ok := ignoreHeaders[keyS]; !ok {

middleware/cache/cache_test.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"math"
-	"net/http"
 	"net/http/httptest"
 	"os"
 	"strconv"
@@ -18,6 +17,7 @@ import (
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 	"github.com/gofiber/fiber/v2/middleware/etag"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -35,10 +35,10 @@ func Test_Cache_CacheControl(t *testing.T) {
 		return c.SendString("Hello, World!")
 	})
 
-	_, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "public, max-age=10", resp.Header.Get(fiber.HeaderCacheControl))
 }
@@ -53,7 +53,7 @@ func Test_Cache_Expired(t *testing.T) {
 		return c.SendString(fmt.Sprintf("%d", time.Now().UnixNano()))
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
@@ -61,7 +61,7 @@ func Test_Cache_Expired(t *testing.T) {
 	// Sleep until the cache is expired
 	time.Sleep(3 * time.Second)
 
-	respCached, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	respCached, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	bodyCached, err := io.ReadAll(respCached.Body)
 	utils.AssertEqual(t, nil, err)
@@ -71,7 +71,7 @@ func Test_Cache_Expired(t *testing.T) {
 	}
 
 	// Next response should be also cached
-	respCachedNextRound, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	respCachedNextRound, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	bodyCachedNextRound, err := io.ReadAll(respCachedNextRound.Body)
 	utils.AssertEqual(t, nil, err)
@@ -92,11 +92,11 @@ func Test_Cache(t *testing.T) {
 		return c.SendString(now)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
-	cachedReq := httptest.NewRequest("GET", "/", nil)
+	cachedReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	cachedResp, err := app.Test(cachedReq)
 	utils.AssertEqual(t, nil, err)
 
@@ -120,31 +120,31 @@ func Test_Cache_WithNoCacheRequestDirective(t *testing.T) {
 	})
 
 	// Request id = 1
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err := app.Test(req)
-	defer resp.Body.Close()
-	body, _ := io.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, resp.Header.Get("X-Cache"))
 	utils.AssertEqual(t, []byte("1"), body)
 	// Response cached, entry id = 1
 
 	// Request id = 2 without Cache-Control: no-cache
-	cachedReq := httptest.NewRequest("GET", "/?id=2", nil)
+	cachedReq := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	cachedResp, err := app.Test(cachedReq)
-	defer cachedResp.Body.Close()
-	cachedBody, _ := io.ReadAll(cachedResp.Body)
+	utils.AssertEqual(t, nil, err)
+	cachedBody, err := io.ReadAll(cachedResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheHit, cachedResp.Header.Get("X-Cache"))
 	utils.AssertEqual(t, []byte("1"), cachedBody)
 	// Response not cached, returns cached response, entry id = 1
 
 	// Request id = 2 with Cache-Control: no-cache
-	noCacheReq := httptest.NewRequest("GET", "/?id=2", nil)
+	noCacheReq := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	noCacheReq.Header.Set(fiber.HeaderCacheControl, noCache)
 	noCacheResp, err := app.Test(noCacheReq)
-	defer noCacheResp.Body.Close()
-	noCacheBody, _ := io.ReadAll(noCacheResp.Body)
+	utils.AssertEqual(t, nil, err)
+	noCacheBody, err := io.ReadAll(noCacheResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, noCacheResp.Header.Get("X-Cache"))
 	utils.AssertEqual(t, []byte("2"), noCacheBody)
@@ -152,21 +152,21 @@ func Test_Cache_WithNoCacheRequestDirective(t *testing.T) {
 
 	/* Check Test_Cache_WithETagAndNoCacheRequestDirective */
 	// Request id = 2 with Cache-Control: no-cache again
-	noCacheReq1 := httptest.NewRequest("GET", "/?id=2", nil)
+	noCacheReq1 := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	noCacheReq1.Header.Set(fiber.HeaderCacheControl, noCache)
 	noCacheResp1, err := app.Test(noCacheReq1)
-	defer noCacheResp1.Body.Close()
-	noCacheBody1, _ := io.ReadAll(noCacheResp1.Body)
+	utils.AssertEqual(t, nil, err)
+	noCacheBody1, err := io.ReadAll(noCacheResp1.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, noCacheResp1.Header.Get("X-Cache"))
 	utils.AssertEqual(t, []byte("2"), noCacheBody1)
 	// Response cached, returns updated response, entry = 2
 
 	// Request id = 1 without Cache-Control: no-cache
-	cachedReq1 := httptest.NewRequest("GET", "/", nil)
+	cachedReq1 := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	cachedResp1, err := app.Test(cachedReq1)
-	defer cachedResp1.Body.Close()
-	cachedBody1, _ := io.ReadAll(cachedResp1.Body)
+	utils.AssertEqual(t, nil, err)
+	cachedBody1, err := io.ReadAll(cachedResp1.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheHit, cachedResp1.Header.Get("X-Cache"))
 	utils.AssertEqual(t, []byte("2"), cachedBody1)
@@ -188,7 +188,7 @@ func Test_Cache_WithETagAndNoCacheRequestDirective(t *testing.T) {
 	})
 
 	// Request id = 1
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, resp.Header.Get("X-Cache"))
@@ -199,7 +199,7 @@ func Test_Cache_WithETagAndNoCacheRequestDirective(t *testing.T) {
 	etagToken := resp.Header.Get("Etag")
 
 	// Request id = 2 with ETag but without Cache-Control: no-cache
-	cachedReq := httptest.NewRequest("GET", "/?id=2", nil)
+	cachedReq := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	cachedReq.Header.Set(fiber.HeaderIfNoneMatch, etagToken)
 	cachedResp, err := app.Test(cachedReq)
 	utils.AssertEqual(t, nil, err)
@@ -208,7 +208,7 @@ func Test_Cache_WithETagAndNoCacheRequestDirective(t *testing.T) {
 	// Response not cached, returns cached response, entry id = 1, status not modified
 
 	// Request id = 2 with ETag and Cache-Control: no-cache
-	noCacheReq := httptest.NewRequest("GET", "/?id=2", nil)
+	noCacheReq := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	noCacheReq.Header.Set(fiber.HeaderCacheControl, noCache)
 	noCacheReq.Header.Set(fiber.HeaderIfNoneMatch, etagToken)
 	noCacheResp, err := app.Test(noCacheReq)
@@ -221,7 +221,7 @@ func Test_Cache_WithETagAndNoCacheRequestDirective(t *testing.T) {
 	etagToken = noCacheResp.Header.Get("Etag")
 
 	// Request id = 2 with ETag and Cache-Control: no-cache again
-	noCacheReq1 := httptest.NewRequest("GET", "/?id=2", nil)
+	noCacheReq1 := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	noCacheReq1.Header.Set(fiber.HeaderCacheControl, noCache)
 	noCacheReq1.Header.Set(fiber.HeaderIfNoneMatch, etagToken)
 	noCacheResp1, err := app.Test(noCacheReq1)
@@ -231,7 +231,7 @@ func Test_Cache_WithETagAndNoCacheRequestDirective(t *testing.T) {
 	// Response cached, returns updated response, entry id = 2, status not modified
 
 	// Request id = 1 without ETag and Cache-Control: no-cache
-	cachedReq1 := httptest.NewRequest("GET", "/", nil)
+	cachedReq1 := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	cachedResp1, err := app.Test(cachedReq1)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheHit, cachedResp1.Header.Get("X-Cache"))
@@ -251,11 +251,11 @@ func Test_Cache_WithNoStoreRequestDirective(t *testing.T) {
 	})
 
 	// Request id = 2
-	noStoreReq := httptest.NewRequest("GET", "/?id=2", nil)
+	noStoreReq := httptest.NewRequest(fiber.MethodGet, "/?id=2", nil)
 	noStoreReq.Header.Set(fiber.HeaderCacheControl, noStore)
 	noStoreResp, err := app.Test(noStoreReq)
-	defer noStoreResp.Body.Close()
-	noStoreBody, _ := io.ReadAll(noStoreResp.Body)
+	utils.AssertEqual(t, nil, err)
+	noStoreBody, err := io.ReadAll(noStoreResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, []byte("2"), noStoreBody)
 	// Response not cached, returns updated response
@@ -278,11 +278,11 @@ func Test_Cache_WithSeveralRequests(t *testing.T) {
 	for runs := 0; runs < 10; runs++ {
 		for i := 0; i < 10; i++ {
 			func(id int) {
-				rsp, err := app.Test(httptest.NewRequest(http.MethodGet, fmt.Sprintf("/%d", id), nil))
+				rsp, err := app.Test(httptest.NewRequest(fiber.MethodGet, fmt.Sprintf("/%d", id), nil))
 				utils.AssertEqual(t, nil, err)
 
-				defer func(Body io.ReadCloser) {
-					err := Body.Close()
+				defer func(body io.ReadCloser) {
+					err := body.Close()
 					utils.AssertEqual(t, nil, err)
 				}(rsp.Body)
 
@@ -311,11 +311,11 @@ func Test_Cache_Invalid_Expiration(t *testing.T) {
 		return c.SendString(now)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
-	cachedReq := httptest.NewRequest("GET", "/", nil)
+	cachedReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	cachedResp, err := app.Test(cachedReq)
 	utils.AssertEqual(t, nil, err)
 
@@ -342,25 +342,25 @@ func Test_Cache_Get(t *testing.T) {
 		return c.SendString(c.Query("cache"))
 	})
 
-	resp, err := app.Test(httptest.NewRequest("POST", "/?cache=123", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodPost, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("POST", "/?cache=12345", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodPost, "/?cache=12345", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "12345", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/get?cache=123", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/get?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/get?cache=12345", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/get?cache=12345", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
@@ -384,25 +384,25 @@ func Test_Cache_Post(t *testing.T) {
 		return c.SendString(c.Query("cache"))
 	})
 
-	resp, err := app.Test(httptest.NewRequest("POST", "/?cache=123", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodPost, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("POST", "/?cache=12345", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodPost, "/?cache=12345", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/get?cache=123", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/get?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(body))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/get?cache=12345", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/get?cache=12345", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err = io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
@@ -420,14 +420,14 @@ func Test_Cache_NothingToCache(t *testing.T) {
 		return c.SendString(time.Now().String())
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 
 	time.Sleep(500 * time.Millisecond)
 
-	respCached, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	respCached, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	bodyCached, err := io.ReadAll(respCached.Body)
 	utils.AssertEqual(t, nil, err)
@@ -457,22 +457,22 @@ func Test_Cache_CustomNext(t *testing.T) {
 		return c.Status(fiber.StatusInternalServerError).SendString(time.Now().String())
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	body, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
 
-	respCached, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	respCached, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	bodyCached, err := io.ReadAll(respCached.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, true, bytes.Equal(body, bodyCached))
 	utils.AssertEqual(t, true, respCached.Header.Get(fiber.HeaderCacheControl) != "")
 
-	_, err = app.Test(httptest.NewRequest("GET", "/error", nil))
+	_, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/error", nil))
 	utils.AssertEqual(t, nil, err)
 
-	errRespCached, err := app.Test(httptest.NewRequest("GET", "/error", nil))
+	errRespCached, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/error", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, true, errRespCached.Header.Get(fiber.HeaderCacheControl) == "")
 }
@@ -491,7 +491,7 @@ func Test_CustomKey(t *testing.T) {
 		return c.SendString("hi")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	_, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, true, called)
@@ -505,7 +505,9 @@ func Test_CustomExpiration(t *testing.T) {
 	var newCacheTime int
 	app.Use(New(Config{ExpirationGenerator: func(c *fiber.Ctx, cfg *Config) time.Duration {
 		called = true
-		newCacheTime, _ = strconv.Atoi(c.GetRespHeader("Cache-Time", "600"))
+		var err error
+		newCacheTime, err = strconv.Atoi(c.GetRespHeader("Cache-Time", "600"))
+		utils.AssertEqual(t, nil, err)
 		return time.Second * time.Duration(newCacheTime)
 	}}))
 
@@ -515,7 +517,7 @@ func Test_CustomExpiration(t *testing.T) {
 		return c.SendString(now)
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, true, called)
 	utils.AssertEqual(t, 1, newCacheTime)
@@ -523,7 +525,7 @@ func Test_CustomExpiration(t *testing.T) {
 	// Sleep until the cache is expired
 	time.Sleep(1 * time.Second)
 
-	cachedResp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	cachedResp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 
 	body, err := io.ReadAll(resp.Body)
@@ -536,7 +538,7 @@ func Test_CustomExpiration(t *testing.T) {
 	}
 
 	// Next response should be cached
-	cachedRespNextRound, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	cachedRespNextRound, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	cachedBodyNextRound, err := io.ReadAll(cachedRespNextRound.Body)
 	utils.AssertEqual(t, nil, err)
@@ -559,12 +561,12 @@ func Test_AdditionalE2EResponseHeaders(t *testing.T) {
 		return c.SendString("hi")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "foobar", resp.Header.Get("X-Foobar"))
 
-	req = httptest.NewRequest("GET", "/", nil)
+	req = httptest.NewRequest(fiber.MethodGet, "/", nil)
 	resp, err = app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "foobar", resp.Header.Get("X-Foobar"))
@@ -594,19 +596,19 @@ func Test_CacheHeader(t *testing.T) {
 		return c.Status(fiber.StatusInternalServerError).SendString(time.Now().String())
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, resp.Header.Get("X-Cache"))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheHit, resp.Header.Get("X-Cache"))
 
-	resp, err = app.Test(httptest.NewRequest("POST", "/?cache=12345", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodPost, "/?cache=12345", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheUnreachable, resp.Header.Get("X-Cache"))
 
-	errRespCached, err := app.Test(httptest.NewRequest("GET", "/error", nil))
+	errRespCached, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/error", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheUnreachable, errRespCached.Header.Get("X-Cache"))
 }
@@ -622,12 +624,12 @@ func Test_Cache_WithHead(t *testing.T) {
 		return c.SendString(now)
 	})
 
-	req := httptest.NewRequest("HEAD", "/", nil)
+	req := httptest.NewRequest(fiber.MethodHead, "/", nil)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, resp.Header.Get("X-Cache"))
 
-	cachedReq := httptest.NewRequest("HEAD", "/", nil)
+	cachedReq := httptest.NewRequest(fiber.MethodHead, "/", nil)
 	cachedResp, err := app.Test(cachedReq)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheHit, cachedResp.Header.Get("X-Cache"))
@@ -649,28 +651,28 @@ func Test_Cache_WithHeadThenGet(t *testing.T) {
 		return c.SendString(c.Query("cache"))
 	})
 
-	headResp, err := app.Test(httptest.NewRequest("HEAD", "/?cache=123", nil))
+	headResp, err := app.Test(httptest.NewRequest(fiber.MethodHead, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	headBody, err := io.ReadAll(headResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "", string(headBody))
 	utils.AssertEqual(t, cacheMiss, headResp.Header.Get("X-Cache"))
 
-	headResp, err = app.Test(httptest.NewRequest("HEAD", "/?cache=123", nil))
+	headResp, err = app.Test(httptest.NewRequest(fiber.MethodHead, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	headBody, err = io.ReadAll(headResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "", string(headBody))
 	utils.AssertEqual(t, cacheHit, headResp.Header.Get("X-Cache"))
 
-	getResp, err := app.Test(httptest.NewRequest("GET", "/?cache=123", nil))
+	getResp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	getBody, err := io.ReadAll(getResp.Body)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "123", string(getBody))
 	utils.AssertEqual(t, cacheMiss, getResp.Header.Get("X-Cache"))
 
-	getResp, err = app.Test(httptest.NewRequest("GET", "/?cache=123", nil))
+	getResp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/?cache=123", nil))
 	utils.AssertEqual(t, nil, err)
 	getBody, err = io.ReadAll(getResp.Body)
 	utils.AssertEqual(t, nil, err)
@@ -691,7 +693,7 @@ func Test_CustomCacheHeader(t *testing.T) {
 		return c.SendString("Hello, World!")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, cacheMiss, resp.Header.Get("Cache-Status"))
 }
@@ -702,7 +704,7 @@ func Test_CustomCacheHeader(t *testing.T) {
 func stableAscendingExpiration() func(c1 *fiber.Ctx, c2 *Config) time.Duration {
 	i := 0
 	return func(c1 *fiber.Ctx, c2 *Config) time.Duration {
-		i += 1
+		i++
 		return time.Hour * time.Duration(i)
 	}
 }
@@ -738,7 +740,7 @@ func Test_Cache_MaxBytesOrder(t *testing.T) {
 	}
 
 	for idx, tcase := range cases {
-		rsp, err := app.Test(httptest.NewRequest("GET", tcase[0], nil))
+		rsp, err := app.Test(httptest.NewRequest(fiber.MethodGet, tcase[0], nil))
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, tcase[1], rsp.Header.Get("X-Cache"), fmt.Sprintf("Case %v", idx))
 	}
@@ -756,7 +758,8 @@ func Test_Cache_MaxBytesSizes(t *testing.T) {
 
 	app.Get("/*", func(c *fiber.Ctx) error {
 		path := c.Context().URI().LastPathSegment()
-		size, _ := strconv.Atoi(string(path))
+		size, err := strconv.Atoi(string(path))
+		utils.AssertEqual(t, nil, err)
 		return c.Send(make([]byte, size))
 	})
 
@@ -772,7 +775,7 @@ func Test_Cache_MaxBytesSizes(t *testing.T) {
 	}
 
 	for idx, tcase := range cases {
-		rsp, err := app.Test(httptest.NewRequest("GET", tcase[0], nil))
+		rsp, err := app.Test(httptest.NewRequest(fiber.MethodGet, tcase[0], nil))
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, tcase[1], rsp.Header.Get("X-Cache"), fmt.Sprintf("Case %v", idx))
 	}
@@ -785,14 +788,14 @@ func Benchmark_Cache(b *testing.B) {
 	app.Use(New())
 
 	app.Get("/demo", func(c *fiber.Ctx) error {
-		data, _ := os.ReadFile("../../.github/README.md")
+		data, _ := os.ReadFile("../../.github/README.md") //nolint:errcheck // We're inside a benchmark
 		return c.Status(fiber.StatusTeapot).Send(data)
 	})
 
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/demo")
 
 	b.ReportAllocs()
@@ -815,14 +818,14 @@ func Benchmark_Cache_Storage(b *testing.B) {
 	}))
 
 	app.Get("/demo", func(c *fiber.Ctx) error {
-		data, _ := os.ReadFile("../../.github/README.md")
+		data, _ := os.ReadFile("../../.github/README.md") //nolint:errcheck // We're inside a benchmark
 		return c.Status(fiber.StatusTeapot).Send(data)
 	})
 
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/demo")
 
 	b.ReportAllocs()
@@ -850,7 +853,7 @@ func Benchmark_Cache_AdditionalHeaders(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/demo")
 
 	b.ReportAllocs()
@@ -882,7 +885,7 @@ func Benchmark_Cache_MaxSize(b *testing.B) {
 
 			h := app.Handler()
 			fctx := &fasthttp.RequestCtx{}
-			fctx.Request.Header.SetMethod("GET")
+			fctx.Request.Header.SetMethod(fiber.MethodGet)
 
 			b.ReportAllocs()
 			b.ResetTimer()

middleware/cache/config.go

@@ -1,7 +1,7 @@
 package cache
 
 import (
-	"fmt"
+	"log"
 	"time"
 
 	"github.com/gofiber/fiber/v2"
@@ -49,10 +49,10 @@ type Config struct {
 	// Default: an in memory store for this process only
 	Storage fiber.Storage
 
-	// Deprecated, use Storage instead
+	// Deprecated: Use Storage instead
 	Store fiber.Storage
 
-	// Deprecated, use KeyGenerator instead
+	// Deprecated: Use KeyGenerator instead
 	Key func(*fiber.Ctx) string
 
 	// allows you to store additional headers generated by next middlewares & handler
@@ -75,6 +75,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:         nil,
 	Expiration:   1 * time.Minute,
@@ -102,11 +104,11 @@ func configDefault(config ...Config) Config {
 
 	// Set default values
 	if cfg.Store != nil {
-		fmt.Println("[CACHE] Store is deprecated, please use Storage")
+		log.Printf("[CACHE] Store is deprecated, please use Storage\n")
 		cfg.Storage = cfg.Store
 	}
 	if cfg.Key != nil {
-		fmt.Println("[CACHE] Key is deprecated, please use KeyGenerator")
+		log.Printf("[CACHE] Key is deprecated, please use KeyGenerator\n")
 		cfg.KeyGenerator = cfg.Key
 	}
 	if cfg.Next == nil {

middleware/cache/heap.go

@@ -41,7 +41,7 @@ func (h indexedHeap) Swap(i, j int) {
 }
 
 func (h *indexedHeap) Push(x interface{}) {
-	h.pushInternal(x.(heapEntry))
+	h.pushInternal(x.(heapEntry)) //nolint:forcetypeassert // Forced type assertion required to implement the heap.Interface interface
 }
 
 func (h *indexedHeap) Pop() interface{} {
@@ -65,7 +65,7 @@ func (h *indexedHeap) put(key string, exp uint64, bytes uint) int {
 		idx = h.entries[:n+1][n].idx
 	} else {
 		idx = h.maxidx
-		h.maxidx += 1
+		h.maxidx++
 		h.indices = append(h.indices, idx)
 	}
 	// Push manually to avoid allocation
@@ -77,7 +77,7 @@ func (h *indexedHeap) put(key string, exp uint64, bytes uint) int {
 }
 
 func (h *indexedHeap) removeInternal(realIdx int) (string, uint) {
-	x := heap.Remove(h, realIdx).(heapEntry)
+	x := heap.Remove(h, realIdx).(heapEntry) //nolint:forcetypeassert,errcheck // Forced type assertion required to implement the heap.Interface interface
 	return x.key, x.bytes
 }
 

middleware/cache/manager.go

@@ -51,7 +51,7 @@ func newManager(storage fiber.Storage) *manager {
 
 // acquire returns an *entry from the sync.Pool
 func (m *manager) acquire() *item {
-	return m.pool.Get().(*item)
+	return m.pool.Get().(*item) //nolint:forcetypeassert // We store nothing else in the pool
 }
 
 // release and reset *entry to sync.Pool
@@ -69,38 +69,47 @@ func (m *manager) release(e *item) {
 }
 
 // get data from storage or memory
-func (m *manager) get(key string) (it *item) {
+func (m *manager) get(key string) *item {
+	var it *item
 	if m.storage != nil {
 		it = m.acquire()
-		if raw, _ := m.storage.Get(key); raw != nil {
+		raw, err := m.storage.Get(key)
+		if err != nil {
+			return it
+		}
+		if raw != nil {
 			if _, err := it.UnmarshalMsg(raw); err != nil {
-				return
+				return it
 			}
 		}
-		return
+		return it
 	}
-	if it, _ = m.memory.Get(key).(*item); it == nil {
+	if it, _ = m.memory.Get(key).(*item); it == nil { //nolint:errcheck // We store nothing else in the pool
 		it = m.acquire()
+		return it
 	}
-	return
+	return it
 }
 
 // get raw data from storage or memory
-func (m *manager) getRaw(key string) (raw []byte) {
+func (m *manager) getRaw(key string) []byte {
+	var raw []byte
 	if m.storage != nil {
-		raw, _ = m.storage.Get(key)
+		raw, _ = m.storage.Get(key) //nolint:errcheck // TODO: Handle error here
 	} else {
-		raw, _ = m.memory.Get(key).([]byte)
+		raw, _ = m.memory.Get(key).([]byte) //nolint:errcheck // TODO: Handle error here
 	}
-	return
+	return raw
 }
 
 // set data to storage or memory
 func (m *manager) set(key string, it *item, exp time.Duration) {
 	if m.storage != nil {
 		if raw, err := it.MarshalMsg(nil); err == nil {
-			_ = m.storage.Set(key, raw, exp)
+			_ = m.storage.Set(key, raw, exp) //nolint:errcheck // TODO: Handle error here
 		}
+		// we can release data because it's serialized to database
+		m.release(it)
 	} else {
 		m.memory.Set(key, it, exp)
 	}
@@ -109,16 +118,16 @@ func (m *manager) set(key string, it *item, exp time.Duration) {
 // set data to storage or memory
 func (m *manager) setRaw(key string, raw []byte, exp time.Duration) {
 	if m.storage != nil {
-		_ = m.storage.Set(key, raw, exp)
+		_ = m.storage.Set(key, raw, exp) //nolint:errcheck // TODO: Handle error here
 	} else {
 		m.memory.Set(key, raw, exp)
 	}
 }
 
 // delete data from storage or memory
-func (m *manager) delete(key string) {
+func (m *manager) del(key string) {
 	if m.storage != nil {
-		_ = m.storage.Delete(key)
+		_ = m.storage.Delete(key) //nolint:errcheck // TODO: Handle error here
 	} else {
 		m.memory.Delete(key)
 	}

middleware/compress/compress.go

@@ -2,6 +2,7 @@ package compress
 
 import (
 	"github.com/gofiber/fiber/v2"
+
 	"github.com/valyala/fasthttp"
 )
 

middleware/compress/compress_test.go

@@ -12,8 +12,10 @@ import (
 	"github.com/gofiber/fiber/v2/utils"
 )
 
+//nolint:gochecknoglobals // Using a global var is fine here
 var filedata []byte
 
+//nolint:gochecknoinits // init() is used to populate a global var from a README file
 func init() {
 	dat, err := os.ReadFile("../../.github/README.md")
 	if err != nil {
@@ -34,7 +36,7 @@ func Test_Compress_Gzip(t *testing.T) {
 		return c.Send(filedata)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Set("Accept-Encoding", "gzip")
 
 	resp, err := app.Test(req)
@@ -64,7 +66,7 @@ func Test_Compress_Different_Level(t *testing.T) {
 				return c.Send(filedata)
 			})
 
-			req := httptest.NewRequest("GET", "/", nil)
+			req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 			req.Header.Set("Accept-Encoding", "gzip")
 
 			resp, err := app.Test(req)
@@ -90,7 +92,7 @@ func Test_Compress_Deflate(t *testing.T) {
 		return c.Send(filedata)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Set("Accept-Encoding", "deflate")
 
 	resp, err := app.Test(req)
@@ -114,7 +116,7 @@ func Test_Compress_Brotli(t *testing.T) {
 		return c.Send(filedata)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Set("Accept-Encoding", "br")
 
 	resp, err := app.Test(req, 10000)
@@ -138,7 +140,7 @@ func Test_Compress_Disabled(t *testing.T) {
 		return c.Send(filedata)
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Set("Accept-Encoding", "br")
 
 	resp, err := app.Test(req)
@@ -162,7 +164,7 @@ func Test_Compress_Next_Error(t *testing.T) {
 		return errors.New("next error")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Set("Accept-Encoding", "gzip")
 
 	resp, err := app.Test(req)
@@ -185,7 +187,7 @@ func Test_Compress_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }

middleware/compress/config.go

@@ -33,6 +33,8 @@ const (
 )
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:  nil,
 	Level: LevelDefault,

middleware/cors/cors.go

@@ -1,7 +1,6 @@
 package cors
 
 import (
-	"net/http"
 	"strconv"
 	"strings"
 
@@ -54,6 +53,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:         nil,
 	AllowOrigins: "*",
@@ -128,7 +129,7 @@ func New(config ...Config) fiber.Handler {
 		}
 
 		// Simple request
-		if c.Method() != http.MethodOptions {
+		if c.Method() != fiber.MethodOptions {
 			c.Vary(fiber.HeaderOrigin)
 			c.Set(fiber.HeaderAccessControlAllowOrigin, allowOrigin)
 

middleware/cors/cors_test.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -237,7 +238,7 @@ func Test_CORS_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }

middleware/cors/utils.go

@@ -1,6 +1,8 @@
 package cors
 
-import "strings"
+import (
+	"strings"
+)
 
 func matchScheme(domain, pattern string) bool {
 	didx := strings.Index(domain, ":")
@@ -20,18 +22,20 @@ func matchSubdomain(domain, pattern string) bool {
 	}
 	domAuth := domain[didx+3:]
 	// to avoid long loop by invalid long domain
-	if len(domAuth) > 253 {
+	const maxDomainLen = 253
+	if len(domAuth) > maxDomainLen {
 		return false
 	}
 	patAuth := pattern[pidx+3:]
 
 	domComp := strings.Split(domAuth, ".")
 	patComp := strings.Split(patAuth, ".")
-	for i := len(domComp)/2 - 1; i >= 0; i-- {
+	const divHalf = 2
+	for i := len(domComp)/divHalf - 1; i >= 0; i-- {
 		opp := len(domComp) - 1 - i
 		domComp[i], domComp[opp] = domComp[opp], domComp[i]
 	}
-	for i := len(patComp)/2 - 1; i >= 0; i-- {
+	for i := len(patComp)/divHalf - 1; i >= 0; i-- {
 		opp := len(patComp) - 1 - i
 		patComp[i], patComp[opp] = patComp[opp], patComp[i]
 	}

middleware/csrf/config.go

@@ -1,7 +1,7 @@
 package csrf
 
 import (
-	"fmt"
+	"log"
 	"net/textproto"
 	"strings"
 	"time"
@@ -80,13 +80,13 @@ type Config struct {
 	// Optional. Default: utils.UUID
 	KeyGenerator func() string
 
-	// Deprecated, please use Expiration
+	// Deprecated: Please use Expiration
 	CookieExpires time.Duration
 
-	// Deprecated, please use Cookie* related fields
+	// Deprecated: Please use Cookie* related fields
 	Cookie *fiber.Cookie
 
-	// Deprecated, please use KeyLookup
+	// Deprecated: Please use KeyLookup
 	TokenLookup string
 
 	// ErrorHandler is executed when an error is returned from fiber.Handler.
@@ -105,6 +105,8 @@ type Config struct {
 const HeaderName = "X-Csrf-Token"
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	KeyLookup:      "header:" + HeaderName,
 	CookieName:     "csrf_",
@@ -116,7 +118,7 @@ var ConfigDefault = Config{
 }
 
 // default ErrorHandler that process return error from fiber.Handler
-var defaultErrorHandler = func(c *fiber.Ctx, err error) error {
+func defaultErrorHandler(_ *fiber.Ctx, _ error) error {
 	return fiber.ErrForbidden
 }
 
@@ -132,15 +134,15 @@ func configDefault(config ...Config) Config {
 
 	// Set default values
 	if cfg.TokenLookup != "" {
-		fmt.Println("[CSRF] TokenLookup is deprecated, please use KeyLookup")
+		log.Printf("[CSRF] TokenLookup is deprecated, please use KeyLookup\n")
 		cfg.KeyLookup = cfg.TokenLookup
 	}
 	if int(cfg.CookieExpires.Seconds()) > 0 {
-		fmt.Println("[CSRF] CookieExpires is deprecated, please use Expiration")
+		log.Printf("[CSRF] CookieExpires is deprecated, please use Expiration\n")
 		cfg.Expiration = cfg.CookieExpires
 	}
 	if cfg.Cookie != nil {
-		fmt.Println("[CSRF] Cookie is deprecated, please use Cookie* related fields")
+		log.Printf("[CSRF] Cookie is deprecated, please use Cookie* related fields\n")
 		if cfg.Cookie.Name != "" {
 			cfg.CookieName = cfg.Cookie.Name
 		}
@@ -178,7 +180,8 @@ func configDefault(config ...Config) Config {
 	// Generate the correct extractor to get the token from the correct location
 	selectors := strings.Split(cfg.KeyLookup, ":")
 
-	if len(selectors) != 2 {
+	const numParts = 2
+	if len(selectors) != numParts {
 		panic("[CSRF] KeyLookup must in the form of <source>:<key>")
 	}
 

middleware/csrf/csrf.go

@@ -7,9 +7,7 @@ import (
 	"github.com/gofiber/fiber/v2"
 )
 
-var (
-	errTokenNotFound = errors.New("csrf token not found")
-)
+var errTokenNotFound = errors.New("csrf token not found")
 
 // New creates a new middleware handler
 func New(config ...Config) fiber.Handler {
@@ -22,7 +20,7 @@ func New(config ...Config) fiber.Handler {
 	dummyValue := []byte{'+'}
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()
@@ -39,7 +37,7 @@ func New(config ...Config) fiber.Handler {
 			// Assume that anything not defined as 'safe' by RFC7231 needs protection
 
 			// Extract token from client request i.e. header, query, param, form or cookie
-			token, err = cfg.Extractor(c)
+			token, err := cfg.Extractor(c)
 			if err != nil {
 				return cfg.ErrorHandler(c, err)
 			}

middleware/csrf/csrf_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -23,7 +24,7 @@ func Test_CSRF(t *testing.T) {
 	h := app.Handler()
 	ctx := &fasthttp.RequestCtx{}
 
-	methods := [4]string{"GET", "HEAD", "OPTIONS", "TRACE"}
+	methods := [4]string{fiber.MethodGet, fiber.MethodHead, fiber.MethodOptions, fiber.MethodTrace}
 
 	for _, method := range methods {
 		// Generate CSRF token
@@ -33,14 +34,14 @@ func Test_CSRF(t *testing.T) {
 		// Without CSRF cookie
 		ctx.Request.Reset()
 		ctx.Response.Reset()
-		ctx.Request.Header.SetMethod("POST")
+		ctx.Request.Header.SetMethod(fiber.MethodPost)
 		h(ctx)
 		utils.AssertEqual(t, 403, ctx.Response.StatusCode())
 
 		// Empty/invalid CSRF token
 		ctx.Request.Reset()
 		ctx.Response.Reset()
-		ctx.Request.Header.SetMethod("POST")
+		ctx.Request.Header.SetMethod(fiber.MethodPost)
 		ctx.Request.Header.Set(HeaderName, "johndoe")
 		h(ctx)
 		utils.AssertEqual(t, 403, ctx.Response.StatusCode())
@@ -55,7 +56,7 @@ func Test_CSRF(t *testing.T) {
 
 		ctx.Request.Reset()
 		ctx.Response.Reset()
-		ctx.Request.Header.SetMethod("POST")
+		ctx.Request.Header.SetMethod(fiber.MethodPost)
 		ctx.Request.Header.Set(HeaderName, token)
 		h(ctx)
 		utils.AssertEqual(t, 200, ctx.Response.StatusCode())
@@ -72,7 +73,7 @@ func Test_CSRF_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -92,7 +93,7 @@ func Test_CSRF_Invalid_KeyLookup(t *testing.T) {
 
 	h := app.Handler()
 	ctx := &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 }
 
@@ -110,7 +111,7 @@ func Test_CSRF_From_Form(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Invalid CSRF token
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(fiber.HeaderContentType, fiber.MIMEApplicationForm)
 	h(ctx)
 	utils.AssertEqual(t, 403, ctx.Response.StatusCode())
@@ -118,12 +119,12 @@ func Test_CSRF_From_Form(t *testing.T) {
 	// Generate CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
 	token = strings.Split(strings.Split(token, ";")[0], "=")[1]
 
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(fiber.HeaderContentType, fiber.MIMEApplicationForm)
 	ctx.Request.SetBodyString("_csrf=" + token)
 	h(ctx)
@@ -144,7 +145,7 @@ func Test_CSRF_From_Query(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Invalid CSRF token
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.SetRequestURI("/?_csrf=" + utils.UUID())
 	h(ctx)
 	utils.AssertEqual(t, 403, ctx.Response.StatusCode())
@@ -152,7 +153,7 @@ func Test_CSRF_From_Query(t *testing.T) {
 	// Generate CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.SetRequestURI("/")
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
@@ -161,7 +162,7 @@ func Test_CSRF_From_Query(t *testing.T) {
 	ctx.Request.Reset()
 	ctx.Response.Reset()
 	ctx.Request.SetRequestURI("/?_csrf=" + token)
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 	utils.AssertEqual(t, "OK", string(ctx.Response.Body()))
@@ -181,7 +182,7 @@ func Test_CSRF_From_Param(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Invalid CSRF token
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.SetRequestURI("/" + utils.UUID())
 	h(ctx)
 	utils.AssertEqual(t, 403, ctx.Response.StatusCode())
@@ -189,7 +190,7 @@ func Test_CSRF_From_Param(t *testing.T) {
 	// Generate CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.SetRequestURI("/" + utils.UUID())
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
@@ -198,7 +199,7 @@ func Test_CSRF_From_Param(t *testing.T) {
 	ctx.Request.Reset()
 	ctx.Response.Reset()
 	ctx.Request.SetRequestURI("/" + token)
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 	utils.AssertEqual(t, "OK", string(ctx.Response.Body()))
@@ -218,7 +219,7 @@ func Test_CSRF_From_Cookie(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Invalid CSRF token
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.SetRequestURI("/")
 	ctx.Request.Header.Set(fiber.HeaderCookie, "csrf="+utils.UUID()+";")
 	h(ctx)
@@ -227,7 +228,7 @@ func Test_CSRF_From_Cookie(t *testing.T) {
 	// Generate CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.SetRequestURI("/")
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
@@ -235,7 +236,7 @@ func Test_CSRF_From_Cookie(t *testing.T) {
 
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(fiber.HeaderCookie, "csrf="+token+";")
 	ctx.Request.SetRequestURI("/")
 	h(ctx)
@@ -268,7 +269,7 @@ func Test_CSRF_From_Custom(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Invalid CSRF token
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(fiber.HeaderContentType, fiber.MIMETextPlain)
 	h(ctx)
 	utils.AssertEqual(t, 403, ctx.Response.StatusCode())
@@ -276,12 +277,12 @@ func Test_CSRF_From_Custom(t *testing.T) {
 	// Generate CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
 	token = strings.Split(strings.Split(token, ";")[0], "=")[1]
 
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(fiber.HeaderContentType, fiber.MIMETextPlain)
 	ctx.Request.SetBodyString("_csrf=" + token)
 	h(ctx)
@@ -307,13 +308,13 @@ func Test_CSRF_ErrorHandler_InvalidToken(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Generate CSRF token
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 
 	// invalid CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(HeaderName, "johndoe")
 	h(ctx)
 	utils.AssertEqual(t, 419, ctx.Response.StatusCode())
@@ -339,69 +340,69 @@ func Test_CSRF_ErrorHandler_EmptyToken(t *testing.T) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Generate CSRF token
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 
 	// empty CSRF token
 	ctx.Request.Reset()
 	ctx.Response.Reset()
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	h(ctx)
 	utils.AssertEqual(t, 419, ctx.Response.StatusCode())
 	utils.AssertEqual(t, "empty CSRF token", string(ctx.Response.Body()))
 }
 
 // TODO: use this test case and make the unsafe header value bug from https://github.com/gofiber/fiber/issues/2045 reproducible and permanently fixed/tested by this testcase
-//func Test_CSRF_UnsafeHeaderValue(t *testing.T) {
+// func Test_CSRF_UnsafeHeaderValue(t *testing.T) {
 //  t.Parallel()
-//	app := fiber.New()
-//
-//	app.Use(New())
-//	app.Get("/", func(c *fiber.Ctx) error {
-//		return c.SendStatus(fiber.StatusOK)
-//	})
-//	app.Get("/test", func(c *fiber.Ctx) error {
-//		return c.SendStatus(fiber.StatusOK)
-//	})
-//	app.Post("/", func(c *fiber.Ctx) error {
-//		return c.SendStatus(fiber.StatusOK)
-//	})
-//
-//	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
-//	utils.AssertEqual(t, nil, err)
-//	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
-//
-//	var token string
-//	for _, c := range resp.Cookies() {
-//		if c.Name != ConfigDefault.CookieName {
-//			continue
-//		}
-//		token = c.Value
-//		break
-//	}
-//
-//	fmt.Println("token", token)
-//
-//	getReq := httptest.NewRequest(http.MethodGet, "/", nil)
-//	getReq.Header.Set(HeaderName, token)
-//	resp, err = app.Test(getReq)
-//
-//	getReq = httptest.NewRequest(http.MethodGet, "/test", nil)
-//	getReq.Header.Set("X-Requested-With", "XMLHttpRequest")
-//	getReq.Header.Set(fiber.HeaderCacheControl, "no")
-//	getReq.Header.Set(HeaderName, token)
-//
-//	resp, err = app.Test(getReq)
-//
-//	getReq.Header.Set(fiber.HeaderAccept, "*/*")
-//	getReq.Header.Del(HeaderName)
-//	resp, err = app.Test(getReq)
-//
-//	postReq := httptest.NewRequest(http.MethodPost, "/", nil)
-//	postReq.Header.Set("X-Requested-With", "XMLHttpRequest")
-//	postReq.Header.Set(HeaderName, token)
-//	resp, err = app.Test(postReq)
-//}
+// 	app := fiber.New()
+
+// 	app.Use(New())
+// 	app.Get("/", func(c *fiber.Ctx) error {
+// 		return c.SendStatus(fiber.StatusOK)
+// 	})
+// 	app.Get("/test", func(c *fiber.Ctx) error {
+// 		return c.SendStatus(fiber.StatusOK)
+// 	})
+// 	app.Post("/", func(c *fiber.Ctx) error {
+// 		return c.SendStatus(fiber.StatusOK)
+// 	})
+
+// 	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+// 	utils.AssertEqual(t, nil, err)
+// 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
+
+// 	var token string
+// 	for _, c := range resp.Cookies() {
+// 		if c.Name != ConfigDefault.CookieName {
+// 			continue
+// 		}
+// 		token = c.Value
+// 		break
+// 	}
+
+// 	fmt.Println("token", token)
+
+// 	getReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
+// 	getReq.Header.Set(HeaderName, token)
+// 	resp, err = app.Test(getReq)
+
+// 	getReq = httptest.NewRequest(fiber.MethodGet, "/test", nil)
+// 	getReq.Header.Set("X-Requested-With", "XMLHttpRequest")
+// 	getReq.Header.Set(fiber.HeaderCacheControl, "no")
+// 	getReq.Header.Set(HeaderName, token)
+
+// 	resp, err = app.Test(getReq)
+
+// 	getReq.Header.Set(fiber.HeaderAccept, "*/*")
+// 	getReq.Header.Del(HeaderName)
+// 	resp, err = app.Test(getReq)
+
+// 	postReq := httptest.NewRequest(fiber.MethodPost, "/", nil)
+// 	postReq.Header.Set("X-Requested-With", "XMLHttpRequest")
+// 	postReq.Header.Set(HeaderName, token)
+// 	resp, err = app.Test(postReq)
+// }
 
 // go test -v -run=^$ -bench=Benchmark_Middleware_CSRF_Check -benchmem -count=4
 func Benchmark_Middleware_CSRF_Check(b *testing.B) {
@@ -417,12 +418,12 @@ func Benchmark_Middleware_CSRF_Check(b *testing.B) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Generate CSRF token
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 	token := string(ctx.Response.Header.Peek(fiber.HeaderSetCookie))
 	token = strings.Split(strings.Split(token, ";")[0], "=")[1]
 
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	ctx.Request.Header.Set(HeaderName, token)
 
 	b.ReportAllocs()
@@ -449,7 +450,7 @@ func Benchmark_Middleware_CSRF_GenerateToken(b *testing.B) {
 	ctx := &fasthttp.RequestCtx{}
 
 	// Generate CSRF token
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	b.ReportAllocs()
 	b.ResetTimer()
 

middleware/csrf/manager.go

@@ -41,74 +41,23 @@ func newManager(storage fiber.Storage) *manager {
 	return manager
 }
 
-// acquire returns an *entry from the sync.Pool
-func (m *manager) acquire() *item {
-	return m.pool.Get().(*item)
-}
-
-// release and reset *entry to sync.Pool
-func (m *manager) release(e *item) {
-	// don't release item if we using memory storage
-	if m.storage != nil {
-		return
-	}
-	m.pool.Put(e)
-}
-
-// get data from storage or memory
-func (m *manager) get(key string) (it *item) {
-	if m.storage != nil {
-		it = m.acquire()
-		if raw, _ := m.storage.Get(key); raw != nil {
-			if _, err := it.UnmarshalMsg(raw); err != nil {
-				return
-			}
-		}
-		return
-	}
-	if it, _ = m.memory.Get(key).(*item); it == nil {
-		it = m.acquire()
-	}
-	return
-}
-
 // get raw data from storage or memory
-func (m *manager) getRaw(key string) (raw []byte) {
+func (m *manager) getRaw(key string) []byte {
+	var raw []byte
 	if m.storage != nil {
-		raw, _ = m.storage.Get(key)
+		raw, _ = m.storage.Get(key) //nolint:errcheck // TODO: Do not ignore error
 	} else {
-		raw, _ = m.memory.Get(key).([]byte)
-	}
-	return
-}
-
-// set data to storage or memory
-func (m *manager) set(key string, it *item, exp time.Duration) {
-	if m.storage != nil {
-		if raw, err := it.MarshalMsg(nil); err == nil {
-			_ = m.storage.Set(key, raw, exp)
-		}
-	} else {
-		// the key is crucial in crsf and sometimes a reference to another value which can be reused later(pool/unsafe values concept), so a copy is made here
-		m.memory.Set(utils.CopyString(key), it, exp)
+		raw, _ = m.memory.Get(key).([]byte) //nolint:errcheck // TODO: Do not ignore error
 	}
+	return raw
 }
 
 // set data to storage or memory
 func (m *manager) setRaw(key string, raw []byte, exp time.Duration) {
 	if m.storage != nil {
-		_ = m.storage.Set(key, raw, exp)
+		_ = m.storage.Set(key, raw, exp) //nolint:errcheck // TODO: Do not ignore error
 	} else {
 		// the key is crucial in crsf and sometimes a reference to another value which can be reused later(pool/unsafe values concept), so a copy is made here
 		m.memory.Set(utils.CopyString(key), raw, exp)
 	}
 }
-
-// delete data from storage or memory
-func (m *manager) delete(key string) {
-	if m.storage != nil {
-		_ = m.storage.Delete(key)
-	} else {
-		m.memory.Delete(key)
-	}
-}

middleware/encryptcookie/config.go

@@ -1,6 +1,8 @@
 package encryptcookie
 
-import "github.com/gofiber/fiber/v2"
+import (
+	"github.com/gofiber/fiber/v2"
+)
 
 // Config defines the config for middleware.
 type Config struct {
@@ -32,6 +34,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:      nil,
 	Except:    []string{"csrf_"},

middleware/encryptcookie/encryptcookie.go

@@ -2,6 +2,7 @@ package encryptcookie
 
 import (
 	"github.com/gofiber/fiber/v2"
+
 	"github.com/valyala/fasthttp"
 )
 

middleware/encryptcookie/encryptcookie_test.go

@@ -7,9 +7,11 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
+//nolint:gochecknoglobals // Using a global var is fine here
 var testKey = GenerateKey()
 
 func Test_Middleware_Encrypt_Cookie(t *testing.T) {
@@ -35,14 +37,14 @@ func Test_Middleware_Encrypt_Cookie(t *testing.T) {
 
 	// Test empty cookie
 	ctx := &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 	utils.AssertEqual(t, "value=", string(ctx.Response.Body()))
 
 	// Test invalid cookie
 	ctx = &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.Header.SetCookie("test", "Invalid")
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
@@ -54,18 +56,19 @@ func Test_Middleware_Encrypt_Cookie(t *testing.T) {
 
 	// Test valid cookie
 	ctx = &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 
 	encryptedCookie := fasthttp.Cookie{}
 	encryptedCookie.SetKey("test")
 	utils.AssertEqual(t, true, ctx.Response.Header.Cookie(&encryptedCookie), "Get cookie value")
-	decryptedCookieValue, _ := DecryptCookie(string(encryptedCookie.Value()), testKey)
+	decryptedCookieValue, err := DecryptCookie(string(encryptedCookie.Value()), testKey)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "SomeThing", decryptedCookieValue)
 
 	ctx = &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.Header.SetCookie("test", string(encryptedCookie.Value()))
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
@@ -91,7 +94,7 @@ func Test_Encrypt_Cookie_Next(t *testing.T) {
 		return nil
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "SomeThing", resp.Cookies()[0].Value)
 }
@@ -123,7 +126,7 @@ func Test_Encrypt_Cookie_Except(t *testing.T) {
 	h := app.Handler()
 
 	ctx := &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 
@@ -135,7 +138,8 @@ func Test_Encrypt_Cookie_Except(t *testing.T) {
 	encryptedCookie := fasthttp.Cookie{}
 	encryptedCookie.SetKey("test2")
 	utils.AssertEqual(t, true, ctx.Response.Header.Cookie(&encryptedCookie), "Get cookie value")
-	decryptedCookieValue, _ := DecryptCookie(string(encryptedCookie.Value()), testKey)
+	decryptedCookieValue, err := DecryptCookie(string(encryptedCookie.Value()), testKey)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "SomeThing", decryptedCookieValue)
 }
 
@@ -169,18 +173,19 @@ func Test_Encrypt_Cookie_Custom_Encryptor(t *testing.T) {
 	h := app.Handler()
 
 	ctx := &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("POST")
+	ctx.Request.Header.SetMethod(fiber.MethodPost)
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())
 
 	encryptedCookie := fasthttp.Cookie{}
 	encryptedCookie.SetKey("test")
 	utils.AssertEqual(t, true, ctx.Response.Header.Cookie(&encryptedCookie), "Get cookie value")
-	decodedBytes, _ := base64.StdEncoding.DecodeString(string(encryptedCookie.Value()))
+	decodedBytes, err := base64.StdEncoding.DecodeString(string(encryptedCookie.Value()))
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, "SomeThing", string(decodedBytes))
 
 	ctx = &fasthttp.RequestCtx{}
-	ctx.Request.Header.SetMethod("GET")
+	ctx.Request.Header.SetMethod(fiber.MethodGet)
 	ctx.Request.Header.SetCookie("test", string(encryptedCookie.Value()))
 	h(ctx)
 	utils.AssertEqual(t, 200, ctx.Response.StatusCode())

middleware/encryptcookie/utils.go

@@ -6,47 +6,56 @@ import (
 	"crypto/rand"
 	"encoding/base64"
 	"errors"
+	"fmt"
 	"io"
 )
 
 // EncryptCookie Encrypts a cookie value with specific encryption key
 func EncryptCookie(value, key string) (string, error) {
-	keyDecoded, _ := base64.StdEncoding.DecodeString(key)
-	plaintext := []byte(value)
+	keyDecoded, err := base64.StdEncoding.DecodeString(key)
+	if err != nil {
+		return "", fmt.Errorf("failed to base64-decode key: %w", err)
+	}
 
 	block, err := aes.NewCipher(keyDecoded)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to create AES cipher: %w", err)
 	}
 
 	gcm, err := cipher.NewGCM(block)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to create GCM mode: %w", err)
 	}
 
 	nonce := make([]byte, gcm.NonceSize())
 	if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to read: %w", err)
 	}
 
-	ciphertext := gcm.Seal(nonce, nonce, plaintext, nil)
+	ciphertext := gcm.Seal(nonce, nonce, []byte(value), nil)
 
 	return base64.StdEncoding.EncodeToString(ciphertext), nil
 }
 
 // DecryptCookie Decrypts a cookie value with specific encryption key
 func DecryptCookie(value, key string) (string, error) {
-	keyDecoded, _ := base64.StdEncoding.DecodeString(key)
-	enc, _ := base64.StdEncoding.DecodeString(value)
+	keyDecoded, err := base64.StdEncoding.DecodeString(key)
+	if err != nil {
+		return "", fmt.Errorf("failed to base64-decode key: %w", err)
+	}
+	enc, err := base64.StdEncoding.DecodeString(value)
+	if err != nil {
+		return "", fmt.Errorf("failed to base64-decode value: %w", err)
+	}
 
 	block, err := aes.NewCipher(keyDecoded)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to create AES cipher: %w", err)
 	}
 
 	gcm, err := cipher.NewGCM(block)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to create GCM mode: %w", err)
 	}
 
 	nonceSize := gcm.NonceSize()
@@ -59,7 +68,7 @@ func DecryptCookie(value, key string) (string, error) {
 
 	plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("failed to decrypt ciphertext: %w", err)
 	}
 
 	return string(plaintext), nil
@@ -67,7 +76,8 @@ func DecryptCookie(value, key string) (string, error) {
 
 // GenerateKey Generates an encryption key
 func GenerateKey() string {
-	ret := make([]byte, 32)
+	const keyLen = 32
+	ret := make([]byte, keyLen)
 
 	if _, err := rand.Read(ret); err != nil {
 		panic(err)

middleware/envvar/envvar.go

@@ -23,10 +23,8 @@ func (envVar *EnvVar) set(key, val string) {
 	envVar.Vars[key] = val
 }
 
-var defaultConfig = Config{}
-
 func New(config ...Config) fiber.Handler {
-	var cfg = defaultConfig
+	var cfg Config
 	if len(config) > 0 {
 		cfg = config[0]
 	}
@@ -57,8 +55,9 @@ func newEnvVar(cfg Config) *EnvVar {
 			}
 		}
 	} else {
+		const numElems = 2
 		for _, envVal := range os.Environ() {
-			keyVal := strings.SplitN(envVal, "=", 2)
+			keyVal := strings.SplitN(envVal, "=", numElems)
 			if _, exists := cfg.ExcludeVars[keyVal[0]]; !exists {
 				vars.set(keyVal[0], keyVal[1])
 			}

middleware/envvar/envvar_test.go

@@ -1,6 +1,8 @@
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package envvar
 
 import (
+	"context"
 	"encoding/json"
 	"io"
 	"net/http"
@@ -12,16 +14,25 @@ import (
 )
 
 func TestEnvVarStructWithExportVarsExcludeVars(t *testing.T) {
-	os.Setenv("testKey", "testEnvValue")
-	os.Setenv("anotherEnvKey", "anotherEnvVal")
-	os.Setenv("excludeKey", "excludeEnvValue")
-	defer os.Unsetenv("testKey")
-	defer os.Unsetenv("anotherEnvKey")
-	defer os.Unsetenv("excludeKey")
+	err := os.Setenv("testKey", "testEnvValue")
+	utils.AssertEqual(t, nil, err)
+	err = os.Setenv("anotherEnvKey", "anotherEnvVal")
+	utils.AssertEqual(t, nil, err)
+	err = os.Setenv("excludeKey", "excludeEnvValue")
+	utils.AssertEqual(t, nil, err)
+	defer func() {
+		err := os.Unsetenv("testKey")
+		utils.AssertEqual(t, nil, err)
+		err = os.Unsetenv("anotherEnvKey")
+		utils.AssertEqual(t, nil, err)
+		err = os.Unsetenv("excludeKey")
+		utils.AssertEqual(t, nil, err)
+	}()
 
 	vars := newEnvVar(Config{
 		ExportVars:  map[string]string{"testKey": "", "testDefaultKey": "testDefaultVal"},
-		ExcludeVars: map[string]string{"excludeKey": ""}})
+		ExcludeVars: map[string]string{"excludeKey": ""},
+	})
 
 	utils.AssertEqual(t, vars.Vars["testKey"], "testEnvValue")
 	utils.AssertEqual(t, vars.Vars["testDefaultKey"], "testDefaultVal")
@@ -30,21 +41,28 @@ func TestEnvVarStructWithExportVarsExcludeVars(t *testing.T) {
 }
 
 func TestEnvVarHandler(t *testing.T) {
-	os.Setenv("testKey", "testVal")
-	defer os.Unsetenv("testKey")
+	err := os.Setenv("testKey", "testVal")
+	utils.AssertEqual(t, nil, err)
+	defer func() {
+		err := os.Unsetenv("testKey")
+		utils.AssertEqual(t, nil, err)
+	}()
 
-	expectedEnvVarResponse, _ := json.Marshal(
+	expectedEnvVarResponse, err := json.Marshal(
 		struct {
 			Vars map[string]string `json:"vars"`
 		}{
 			map[string]string{"testKey": "testVal"},
 		})
+	utils.AssertEqual(t, nil, err)
 
 	app := fiber.New()
 	app.Use("/envvars", New(Config{
-		ExportVars: map[string]string{"testKey": ""}}))
+		ExportVars: map[string]string{"testKey": ""},
+	}))
 
-	req, _ := http.NewRequest("GET", "http://localhost/envvars", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodGet, "http://localhost/envvars", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
@@ -57,14 +75,16 @@ func TestEnvVarHandler(t *testing.T) {
 func TestEnvVarHandlerNotMatched(t *testing.T) {
 	app := fiber.New()
 	app.Use("/envvars", New(Config{
-		ExportVars: map[string]string{"testKey": ""}}))
+		ExportVars: map[string]string{"testKey": ""},
+	}))
 
 	app.Get("/another-path", func(ctx *fiber.Ctx) error {
 		utils.AssertEqual(t, nil, ctx.SendString("OK"))
 		return nil
 	})
 
-	req, _ := http.NewRequest("GET", "http://localhost/another-path", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodGet, "http://localhost/another-path", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
@@ -75,13 +95,18 @@ func TestEnvVarHandlerNotMatched(t *testing.T) {
 }
 
 func TestEnvVarHandlerDefaultConfig(t *testing.T) {
-	os.Setenv("testEnvKey", "testEnvVal")
-	defer os.Unsetenv("testEnvKey")
+	err := os.Setenv("testEnvKey", "testEnvVal")
+	utils.AssertEqual(t, nil, err)
+	defer func() {
+		err := os.Unsetenv("testEnvKey")
+		utils.AssertEqual(t, nil, err)
+	}()
 
 	app := fiber.New()
 	app.Use("/envvars", New())
 
-	req, _ := http.NewRequest("GET", "http://localhost/envvars", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodGet, "http://localhost/envvars", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
@@ -98,7 +123,8 @@ func TestEnvVarHandlerMethod(t *testing.T) {
 	app := fiber.New()
 	app.Use("/envvars", New())
 
-	req, _ := http.NewRequest("POST", "http://localhost/envvars", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodPost, "http://localhost/envvars", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusMethodNotAllowed, resp.StatusCode)
@@ -107,14 +133,19 @@ func TestEnvVarHandlerMethod(t *testing.T) {
 func TestEnvVarHandlerSpecialValue(t *testing.T) {
 	testEnvKey := "testEnvKey"
 	fakeBase64 := "testBase64:TQ=="
-	os.Setenv(testEnvKey, fakeBase64)
-	defer os.Unsetenv(testEnvKey)
+	err := os.Setenv(testEnvKey, fakeBase64)
+	utils.AssertEqual(t, nil, err)
+	defer func() {
+		err := os.Unsetenv(testEnvKey)
+		utils.AssertEqual(t, nil, err)
+	}()
 
 	app := fiber.New()
 	app.Use("/envvars", New())
 	app.Use("/envvars/export", New(Config{ExportVars: map[string]string{testEnvKey: ""}}))
 
-	req, _ := http.NewRequest("GET", "http://localhost/envvars", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodGet, "http://localhost/envvars", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 
@@ -126,7 +157,8 @@ func TestEnvVarHandlerSpecialValue(t *testing.T) {
 	val := envVars.Vars[testEnvKey]
 	utils.AssertEqual(t, fakeBase64, val)
 
-	req, _ = http.NewRequest("GET", "http://localhost/envvars/export", nil)
+	req, err = http.NewRequestWithContext(context.Background(), fiber.MethodGet, "http://localhost/envvars/export", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err = app.Test(req)
 	utils.AssertEqual(t, nil, err)
 

middleware/etag/config.go

@@ -23,6 +23,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Weak: false,
 	Next: nil,

middleware/etag/etag.go

@@ -5,12 +5,8 @@ import (
 	"hash/crc32"
 
 	"github.com/gofiber/fiber/v2"
-	"github.com/valyala/bytebufferpool"
-)
 
-var (
-	normalizedHeaderETag = []byte("Etag")
-	weakPrefix           = []byte("W/")
+	"github.com/valyala/bytebufferpool"
 )
 
 // New creates a new middleware handler
@@ -18,32 +14,38 @@ func New(config ...Config) fiber.Handler {
 	// Set default config
 	cfg := configDefault(config...)
 
-	crc32q := crc32.MakeTable(0xD5828281)
+	var (
+		normalizedHeaderETag = []byte("Etag")
+		weakPrefix           = []byte("W/")
+	)
+
+	const crcPol = 0xD5828281
+	crc32q := crc32.MakeTable(crcPol)
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()
 		}
 
 		// Return err if next handler returns one
-		if err = c.Next(); err != nil {
-			return
+		if err := c.Next(); err != nil {
+			return err
 		}
 
 		// Don't generate ETags for invalid responses
 		if c.Response().StatusCode() != fiber.StatusOK {
-			return
+			return nil
 		}
 		body := c.Response().Body()
 		// Skips ETag if no response body is present
 		if len(body) == 0 {
-			return
+			return nil
 		}
 		// Skip ETag if header is already present
 		if c.Response().Header.PeekBytes(normalizedHeaderETag) != nil {
-			return
+			return nil
 		}
 
 		// Generate ETag for response
@@ -52,14 +54,14 @@ func New(config ...Config) fiber.Handler {
 
 		// Enable weak tag
 		if cfg.Weak {
-			_, _ = bb.Write(weakPrefix)
+			_, _ = bb.Write(weakPrefix) //nolint:errcheck // This will never fail
 		}
 
-		_ = bb.WriteByte('"')
+		_ = bb.WriteByte('"') //nolint:errcheck // This will never fail
 		bb.B = appendUint(bb.Bytes(), uint32(len(body)))
-		_ = bb.WriteByte('-')
+		_ = bb.WriteByte('-') //nolint:errcheck // This will never fail
 		bb.B = appendUint(bb.Bytes(), crc32.Checksum(body, crc32q))
-		_ = bb.WriteByte('"')
+		_ = bb.WriteByte('"') //nolint:errcheck // This will never fail
 
 		etag := bb.Bytes()
 
@@ -78,7 +80,7 @@ func New(config ...Config) fiber.Handler {
 			// W/1 != W/2 || W/1 != 2
 			c.Response().Header.SetCanonical(normalizedHeaderETag, etag)
 
-			return
+			return nil
 		}
 
 		if bytes.Contains(clientEtag, etag) {
@@ -90,7 +92,7 @@ func New(config ...Config) fiber.Handler {
 		// 1 != 2
 		c.Response().Header.SetCanonical(normalizedHeaderETag, etag)
 
-		return
+		return nil
 	}
 }
 
@@ -102,7 +104,7 @@ func appendUint(dst []byte, n uint32) []byte {
 	var q uint32
 	for n >= 10 {
 		i--
-		q = n / 10
+		q = n / 10 //nolint:gomnd // TODO: Explain why we divide by 10 here
 		buf[i] = '0' + byte(n-q*10)
 		n = q
 	}

middleware/etag/etag_test.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -21,7 +22,7 @@ func Test_ETag_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -37,7 +38,7 @@ func Test_ETag_SkipError(t *testing.T) {
 		return fiber.ErrForbidden
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusForbidden, resp.StatusCode)
 }
@@ -53,7 +54,7 @@ func Test_ETag_NotStatusOK(t *testing.T) {
 		return c.SendStatus(fiber.StatusCreated)
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusCreated, resp.StatusCode)
 }
@@ -69,7 +70,7 @@ func Test_ETag_NoBody(t *testing.T) {
 		return nil
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 }
@@ -91,7 +92,7 @@ func Test_ETag_NewEtag(t *testing.T) {
 	})
 }
 
-func testETagNewEtag(t *testing.T, headerIfNoneMatch, matched bool) {
+func testETagNewEtag(t *testing.T, headerIfNoneMatch, matched bool) { //nolint:revive // We're in a test, so using bools as a flow-control is fine
 	t.Helper()
 
 	app := fiber.New()
@@ -102,7 +103,7 @@ func testETagNewEtag(t *testing.T, headerIfNoneMatch, matched bool) {
 		return c.SendString("Hello, World!")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	if headerIfNoneMatch {
 		etag := `"non-match"`
 		if matched {
@@ -145,7 +146,7 @@ func Test_ETag_WeakEtag(t *testing.T) {
 	})
 }
 
-func testETagWeakEtag(t *testing.T, headerIfNoneMatch, matched bool) {
+func testETagWeakEtag(t *testing.T, headerIfNoneMatch, matched bool) { //nolint:revive // We're in a test, so using bools as a flow-control is fine
 	t.Helper()
 
 	app := fiber.New()
@@ -156,7 +157,7 @@ func testETagWeakEtag(t *testing.T, headerIfNoneMatch, matched bool) {
 		return c.SendString("Hello, World!")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	if headerIfNoneMatch {
 		etag := `W/"non-match"`
 		if matched {
@@ -199,7 +200,7 @@ func Test_ETag_CustomEtag(t *testing.T) {
 	})
 }
 
-func testETagCustomEtag(t *testing.T, headerIfNoneMatch, matched bool) {
+func testETagCustomEtag(t *testing.T, headerIfNoneMatch, matched bool) { //nolint:revive // We're in a test, so using bools as a flow-control is fine
 	t.Helper()
 
 	app := fiber.New()
@@ -214,7 +215,7 @@ func testETagCustomEtag(t *testing.T, headerIfNoneMatch, matched bool) {
 		return c.SendString("Hello, World!")
 	})
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	if headerIfNoneMatch {
 		etag := `"non-match"`
 		if matched {
@@ -255,7 +256,7 @@ func Test_ETag_CustomEtagPut(t *testing.T) {
 		return c.SendString("Hello, World!")
 	})
 
-	req := httptest.NewRequest("PUT", "/", nil)
+	req := httptest.NewRequest(fiber.MethodPut, "/", nil)
 	req.Header.Set(fiber.HeaderIfMatch, `"non-match"`)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
@@ -275,7 +276,7 @@ func Benchmark_Etag(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 
 	b.ReportAllocs()

middleware/expvar/config.go

@@ -1,6 +1,8 @@
 package expvar
 
-import "github.com/gofiber/fiber/v2"
+import (
+	"github.com/gofiber/fiber/v2"
+)
 
 // Config defines the config for middleware.
 type Config struct {
@@ -10,6 +12,7 @@ type Config struct {
 	Next func(c *fiber.Ctx) bool
 }
 
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next: nil,
 }

middleware/expvar/expvar.go

@@ -4,6 +4,7 @@ import (
 	"strings"
 
 	"github.com/gofiber/fiber/v2"
+
 	"github.com/valyala/fasthttp/expvarhandler"
 )
 
@@ -29,6 +30,6 @@ func New(config ...Config) fiber.Handler {
 			return nil
 		}
 
-		return c.Redirect("/debug/vars", 302)
+		return c.Redirect("/debug/vars", fiber.StatusFound)
 	}
 }

middleware/favicon/favicon.go

@@ -34,6 +34,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:         nil,
 	File:         "",

middleware/favicon/favicon_test.go

@@ -1,16 +1,18 @@
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package favicon
 
 import (
+	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"os"
 	"strings"
 	"testing"
 
-	"github.com/valyala/fasthttp"
-
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
+	"github.com/valyala/fasthttp"
 )
 
 // go test -run Test_Middleware_Favicon
@@ -25,22 +27,22 @@ func Test_Middleware_Favicon(t *testing.T) {
 	})
 
 	// Skip Favicon middleware
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/favicon.ico", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusNoContent, resp.StatusCode, "Status code")
 
-	resp, err = app.Test(httptest.NewRequest("OPTIONS", "/favicon.ico", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodOptions, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 
-	resp, err = app.Test(httptest.NewRequest("PUT", "/favicon.ico", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodPut, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusMethodNotAllowed, resp.StatusCode, "Status code")
-	utils.AssertEqual(t, "GET, HEAD, OPTIONS", resp.Header.Get(fiber.HeaderAllow))
+	utils.AssertEqual(t, strings.Join([]string{fiber.MethodGet, fiber.MethodHead, fiber.MethodOptions}, ", "), resp.Header.Get(fiber.HeaderAllow))
 }
 
 // go test -run Test_Middleware_Favicon_Not_Found
@@ -70,8 +72,7 @@ func Test_Middleware_Favicon_Found(t *testing.T) {
 		return nil
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/favicon.ico", nil))
-
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 	utils.AssertEqual(t, "image/x-icon", resp.Header.Get(fiber.HeaderContentType))
@@ -83,15 +84,15 @@ func Test_Middleware_Favicon_Found(t *testing.T) {
 // TODO use os.Dir if fiber upgrades to 1.16
 type mockFS struct{}
 
-func (m mockFS) Open(name string) (http.File, error) {
+func (mockFS) Open(name string) (http.File, error) {
 	if name == "/" {
 		name = "."
 	} else {
 		name = strings.TrimPrefix(name, "/")
 	}
-	file, err := os.Open(name)
+	file, err := os.Open(name) //nolint:gosec // We're in a test func, so this is fine
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("failed to open: %w", err)
 	}
 	return file, nil
 }
@@ -106,7 +107,7 @@ func Test_Middleware_Favicon_FileSystem(t *testing.T) {
 		FileSystem: mockFS{},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/favicon.ico", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 	utils.AssertEqual(t, "image/x-icon", resp.Header.Get(fiber.HeaderContentType))
@@ -123,7 +124,7 @@ func Test_Middleware_Favicon_CacheControl(t *testing.T) {
 		File:         "../../.github/testdata/favicon.ico",
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/favicon.ico", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/favicon.ico", nil))
 	utils.AssertEqual(t, nil, err, "app.Test(req)")
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 	utils.AssertEqual(t, "image/x-icon", resp.Header.Get(fiber.HeaderContentType))
@@ -159,7 +160,7 @@ func Test_Favicon_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }

middleware/filesystem/filesystem.go

@@ -1,6 +1,7 @@
 package filesystem
 
 import (
+	"fmt"
 	"net/http"
 	"os"
 	"strconv"
@@ -55,6 +56,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:       nil,
 	Root:       nil,
@@ -102,7 +105,7 @@ func New(config ...Config) fiber.Handler {
 	cacheControlStr := "public, max-age=" + strconv.Itoa(cfg.MaxAge)
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()
@@ -131,28 +134,23 @@ func New(config ...Config) fiber.Handler {
 			path = cfg.PathPrefix + path
 		}
 
-		var (
-			file http.File
-			stat os.FileInfo
-		)
-
 		if len(path) > 1 {
 			path = utils.TrimRight(path, '/')
 		}
-		file, err = cfg.Root.Open(path)
+		file, err := cfg.Root.Open(path)
 		if err != nil && os.IsNotExist(err) && cfg.NotFoundFile != "" {
 			file, err = cfg.Root.Open(cfg.NotFoundFile)
 		}
-
 		if err != nil {
 			if os.IsNotExist(err) {
 				return c.Status(fiber.StatusNotFound).Next()
 			}
-			return
+			return fmt.Errorf("failed to open: %w", err)
 		}
 
-		if stat, err = file.Stat(); err != nil {
-			return
+		stat, err := file.Stat()
+		if err != nil {
+			return fmt.Errorf("failed to stat: %w", err)
 		}
 
 		// Serve index if path is directory
@@ -200,7 +198,7 @@ func New(config ...Config) fiber.Handler {
 			c.Response().SkipBody = true
 			c.Response().Header.SetContentLength(contentLength)
 			if err := file.Close(); err != nil {
-				return err
+				return fmt.Errorf("failed to close: %w", err)
 			}
 			return nil
 		}
@@ -210,22 +208,18 @@ func New(config ...Config) fiber.Handler {
 }
 
 // SendFile ...
-func SendFile(c *fiber.Ctx, fs http.FileSystem, path string) (err error) {
-	var (
-		file http.File
-		stat os.FileInfo
-	)
-
-	file, err = fs.Open(path)
+func SendFile(c *fiber.Ctx, fs http.FileSystem, path string) error {
+	file, err := fs.Open(path)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return fiber.ErrNotFound
 		}
-		return err
+		return fmt.Errorf("failed to open: %w", err)
 	}
 
-	if stat, err = file.Stat(); err != nil {
-		return err
+	stat, err := file.Stat()
+	if err != nil {
+		return fmt.Errorf("failed to stat: %w", err)
 	}
 
 	// Serve index if path is directory
@@ -268,7 +262,7 @@ func SendFile(c *fiber.Ctx, fs http.FileSystem, path string) (err error) {
 		c.Response().SkipBody = true
 		c.Response().Header.SetContentLength(contentLength)
 		if err := file.Close(); err != nil {
-			return err
+			return fmt.Errorf("failed to close: %w", err)
 		}
 		return nil
 	}

middleware/filesystem/filesystem_test.go

@@ -1,6 +1,8 @@
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package filesystem
 
 import (
+	"context"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -119,7 +121,7 @@ func Test_FileSystem(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			t.Parallel()
-			resp, err := app.Test(httptest.NewRequest("GET", tt.url, nil))
+			resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, tt.url, nil))
 			utils.AssertEqual(t, nil, err)
 			utils.AssertEqual(t, tt.statusCode, resp.StatusCode)
 
@@ -142,7 +144,7 @@ func Test_FileSystem_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -168,7 +170,8 @@ func Test_FileSystem_Head(t *testing.T) {
 		Root: http.Dir("../../.github/testdata/fs"),
 	}))
 
-	req, _ := http.NewRequest(fiber.MethodHead, "/test", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodHead, "/test", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
@@ -182,7 +185,8 @@ func Test_FileSystem_NoRoot(t *testing.T) {
 
 	app := fiber.New()
 	app.Use(New())
-	_, _ = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+	_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+	utils.AssertEqual(t, nil, err)
 }
 
 func Test_FileSystem_UsingParam(t *testing.T) {
@@ -193,7 +197,8 @@ func Test_FileSystem_UsingParam(t *testing.T) {
 		return SendFile(c, http.Dir("../../.github/testdata/fs"), c.Params("path")+".html")
 	})
 
-	req, _ := http.NewRequest(fiber.MethodHead, "/index", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodHead, "/index", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
@@ -207,7 +212,8 @@ func Test_FileSystem_UsingParam_NonFile(t *testing.T) {
 		return SendFile(c, http.Dir("../../.github/testdata/fs"), c.Params("path")+".html")
 	})
 
-	req, _ := http.NewRequest(fiber.MethodHead, "/template", nil)
+	req, err := http.NewRequestWithContext(context.Background(), fiber.MethodHead, "/template", nil)
+	utils.AssertEqual(t, nil, err)
 	resp, err := app.Test(req)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 404, resp.StatusCode)

middleware/filesystem/utils.go

@@ -13,18 +13,18 @@ import (
 	"github.com/gofiber/fiber/v2/utils"
 )
 
-func getFileExtension(path string) string {
-	n := strings.LastIndexByte(path, '.')
+func getFileExtension(p string) string {
+	n := strings.LastIndexByte(p, '.')
 	if n < 0 {
 		return ""
 	}
-	return path[n:]
+	return p[n:]
 }
 
 func dirList(c *fiber.Ctx, f http.File) error {
 	fileinfos, err := f.Readdir(-1)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to read dir: %w", err)
 	}
 
 	fm := make(map[string]os.FileInfo, len(fileinfos))
@@ -36,13 +36,13 @@ func dirList(c *fiber.Ctx, f http.File) error {
 	}
 
 	basePathEscaped := html.EscapeString(c.Path())
-	fmt.Fprintf(c, "<html><head><title>%s</title><style>.dir { font-weight: bold }</style></head><body>", basePathEscaped)
-	fmt.Fprintf(c, "<h1>%s</h1>", basePathEscaped)
-	fmt.Fprint(c, "<ul>")
+	_, _ = fmt.Fprintf(c, "<html><head><title>%s</title><style>.dir { font-weight: bold }</style></head><body>", basePathEscaped)
+	_, _ = fmt.Fprintf(c, "<h1>%s</h1>", basePathEscaped)
+	_, _ = fmt.Fprint(c, "<ul>")
 
 	if len(basePathEscaped) > 1 {
 		parentPathEscaped := html.EscapeString(utils.TrimRight(c.Path(), '/') + "/..")
-		fmt.Fprintf(c, `<li><a href="%s" class="dir">..</a></li>`, parentPathEscaped)
+		_, _ = fmt.Fprintf(c, `<li><a href="%s" class="dir">..</a></li>`, parentPathEscaped)
 	}
 
 	sort.Strings(filenames)
@@ -55,10 +55,10 @@ func dirList(c *fiber.Ctx, f http.File) error {
 			auxStr = fmt.Sprintf("file, %d bytes", fi.Size())
 			className = "file"
 		}
-		fmt.Fprintf(c, `<li><a href="%s" class="%s">%s</a>, %s, last modified %s</li>`,
+		_, _ = fmt.Fprintf(c, `<li><a href="%s" class="%s">%s</a>, %s, last modified %s</li>`,
 			pathEscaped, className, html.EscapeString(name), auxStr, fi.ModTime())
 	}
-	fmt.Fprint(c, "</ul></body></html>")
+	_, _ = fmt.Fprint(c, "</ul></body></html>")
 
 	c.Type("html")
 

middleware/idempotency/config.go

@@ -9,9 +9,7 @@ import (
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 )
 
-var (
-	ErrInvalidIdempotencyKey = errors.New("invalid idempotency key")
-)
+var ErrInvalidIdempotencyKey = errors.New("invalid idempotency key")
 
 // Config defines the config for middleware.
 type Config struct {
@@ -51,13 +49,15 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next: func(c *fiber.Ctx) bool {
 		// Skip middleware if the request was done using a safe HTTP method
 		return fiber.IsMethodSafe(c.Method())
 	},
 
-	Lifetime: 30 * time.Minute,
+	Lifetime: 30 * time.Minute, //nolint:gomnd // No magic number, just the default config
 
 	KeyHeader: "X-Idempotency-Key",
 	KeyHeaderValidate: func(k string) error {
@@ -112,7 +112,7 @@ func configDefault(config ...Config) Config {
 
 	if cfg.Storage == nil {
 		cfg.Storage = memory.New(memory.Config{
-			GCInterval: cfg.Lifetime / 2,
+			GCInterval: cfg.Lifetime / 2, //nolint:gomnd // Half the lifetime interval
 		})
 	}
 

middleware/idempotency/idempotency_test.go

@@ -1,3 +1,4 @@
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package idempotency_test
 
 import (
@@ -14,6 +15,7 @@ import (
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/middleware/idempotency"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -172,5 +174,4 @@ func Benchmark_Idempotency(b *testing.B) {
 			h(c)
 		}
 	})
-
 }

middleware/limiter/config.go

@@ -1,7 +1,7 @@
 package limiter
 
 import (
-	"fmt"
+	"log"
 	"time"
 
 	"github.com/gofiber/fiber/v2"
@@ -58,19 +58,21 @@ type Config struct {
 	// Default: a new Fixed Window Rate Limiter
 	LimiterMiddleware LimiterHandler
 
-	// DEPRECATED: Use Expiration instead
+	// Deprecated: Use Expiration instead
 	Duration time.Duration
 
-	// DEPRECATED, use Storage instead
+	// Deprecated: Use Storage instead
 	Store fiber.Storage
 
-	// DEPRECATED, use KeyGenerator instead
+	// Deprecated: Use KeyGenerator instead
 	Key func(*fiber.Ctx) string
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
-	Max:        5,
+	Max:        5, //nolint:gomnd // No magic number, just the default config
 	Expiration: 1 * time.Minute,
 	KeyGenerator: func(c *fiber.Ctx) string {
 		return c.IP()
@@ -95,15 +97,15 @@ func configDefault(config ...Config) Config {
 
 	// Set default values
 	if int(cfg.Duration.Seconds()) > 0 {
-		fmt.Println("[LIMITER] Duration is deprecated, please use Expiration")
+		log.Printf("[LIMITER] Duration is deprecated, please use Expiration\n")
 		cfg.Expiration = cfg.Duration
 	}
 	if cfg.Key != nil {
-		fmt.Println("[LIMITER] Key is deprecated, please us KeyGenerator")
+		log.Printf("[LIMITER] Key is deprecated, please us KeyGenerator\n")
 		cfg.KeyGenerator = cfg.Key
 	}
 	if cfg.Store != nil {
-		fmt.Println("[LIMITER] Store is deprecated, please use Storage")
+		log.Printf("[LIMITER] Store is deprecated, please use Storage\n")
 		cfg.Storage = cfg.Store
 	}
 	if cfg.Next == nil {

middleware/limiter/limiter_test.go

@@ -2,7 +2,6 @@ package limiter
 
 import (
 	"io"
-	"net/http"
 	"net/http/httptest"
 	"sync"
 	"testing"
@@ -11,6 +10,7 @@ import (
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -34,7 +34,7 @@ func Test_Limiter_Concurrency_Store(t *testing.T) {
 	var wg sync.WaitGroup
 	singleRequest := func(wg *sync.WaitGroup) {
 		defer wg.Done()
-		resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -50,13 +50,13 @@ func Test_Limiter_Concurrency_Store(t *testing.T) {
 
 	wg.Wait()
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 429, resp.StatusCode)
 
 	time.Sleep(3 * time.Second)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 }
@@ -80,7 +80,7 @@ func Test_Limiter_Concurrency(t *testing.T) {
 	var wg sync.WaitGroup
 	singleRequest := func(wg *sync.WaitGroup) {
 		defer wg.Done()
-		resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -96,13 +96,13 @@ func Test_Limiter_Concurrency(t *testing.T) {
 
 	wg.Wait()
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 429, resp.StatusCode)
 
 	time.Sleep(3 * time.Second)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 }
@@ -120,21 +120,21 @@ func Test_Limiter_No_Skip_Choices(t *testing.T) {
 	}))
 
 	app.Get("/:status", func(c *fiber.Ctx) error {
-		if c.Params("status") == "fail" {
+		if c.Params("status") == "fail" { //nolint:goconst // False positive
 			return c.SendStatus(400)
 		}
 		return c.SendStatus(200)
 	})
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/fail", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/fail", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 400, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 429, resp.StatusCode)
 }
@@ -157,21 +157,21 @@ func Test_Limiter_Skip_Failed_Requests(t *testing.T) {
 		return c.SendStatus(200)
 	})
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/fail", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/fail", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 400, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 429, resp.StatusCode)
 
 	time.Sleep(3 * time.Second)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 }
@@ -196,21 +196,21 @@ func Test_Limiter_Skip_Successful_Requests(t *testing.T) {
 		return c.SendStatus(200)
 	})
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/success", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/success", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 200, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/fail", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/fail", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 400, resp.StatusCode)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/fail", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/fail", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 429, resp.StatusCode)
 
 	time.Sleep(3 * time.Second)
 
-	resp, err = app.Test(httptest.NewRequest(http.MethodGet, "/fail", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/fail", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, 400, resp.StatusCode)
 }
@@ -232,7 +232,7 @@ func Benchmark_Limiter_Custom_Store(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 
 	b.ResetTimer()
@@ -252,7 +252,7 @@ func Test_Limiter_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -271,7 +271,7 @@ func Test_Limiter_Headers(t *testing.T) {
 	})
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 
 	app.Handler()(fctx)
@@ -301,7 +301,7 @@ func Benchmark_Limiter(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 
 	b.ResetTimer()
@@ -327,7 +327,7 @@ func Test_Sliding_Window(t *testing.T) {
 	})
 
 	singleRequest := func(shouldFail bool) {
-		resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/", nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 		if shouldFail {
 			utils.AssertEqual(t, nil, err)
 			utils.AssertEqual(t, 429, resp.StatusCode)

middleware/limiter/manager.go

@@ -46,7 +46,7 @@ func newManager(storage fiber.Storage) *manager {
 
 // acquire returns an *entry from the sync.Pool
 func (m *manager) acquire() *item {
-	return m.pool.Get().(*item)
+	return m.pool.Get().(*item) //nolint:forcetypeassert // We store nothing else in the pool
 }
 
 // release and reset *entry to sync.Pool
@@ -58,37 +58,33 @@ func (m *manager) release(e *item) {
 }
 
 // get data from storage or memory
-func (m *manager) get(key string) (it *item) {
+func (m *manager) get(key string) *item {
+	var it *item
 	if m.storage != nil {
 		it = m.acquire()
-		if raw, _ := m.storage.Get(key); raw != nil {
+		raw, err := m.storage.Get(key)
+		if err != nil {
+			return it
+		}
+		if raw != nil {
 			if _, err := it.UnmarshalMsg(raw); err != nil {
-				return
+				return it
 			}
 		}
-		return
+		return it
 	}
-	if it, _ = m.memory.Get(key).(*item); it == nil {
+	if it, _ = m.memory.Get(key).(*item); it == nil { //nolint:errcheck // We store nothing else in the pool
 		it = m.acquire()
+		return it
 	}
-	return
-}
-
-// get raw data from storage or memory
-func (m *manager) getRaw(key string) (raw []byte) {
-	if m.storage != nil {
-		raw, _ = m.storage.Get(key)
-	} else {
-		raw, _ = m.memory.Get(key).([]byte)
-	}
-	return
+	return it
 }
 
 // set data to storage or memory
 func (m *manager) set(key string, it *item, exp time.Duration) {
 	if m.storage != nil {
 		if raw, err := it.MarshalMsg(nil); err == nil {
-			_ = m.storage.Set(key, raw, exp)
+			_ = m.storage.Set(key, raw, exp) //nolint:errcheck // TODO: Handle error here
 		}
 		// we can release data because it's serialized to database
 		m.release(it)
@@ -96,21 +92,3 @@ func (m *manager) set(key string, it *item, exp time.Duration) {
 		m.memory.Set(key, it, exp)
 	}
 }
-
-// set data to storage or memory
-func (m *manager) setRaw(key string, raw []byte, exp time.Duration) {
-	if m.storage != nil {
-		_ = m.storage.Set(key, raw, exp)
-	} else {
-		m.memory.Set(key, raw, exp)
-	}
-}
-
-// delete data from storage or memory
-func (m *manager) delete(key string) {
-	if m.storage != nil {
-		_ = m.storage.Delete(key)
-	} else {
-		m.memory.Delete(key)
-	}
-}

middleware/logger/README.md

@@ -95,7 +95,7 @@ app.Use(logger.New(logger.Config{
 	TimeZone:   "Asia/Shanghai",
 	Done: func(c *fiber.Ctx, logString []byte) {
 		if c.Response().StatusCode() != fiber.StatusOK {
-			reporter.SendToSlack(logString) 
+			reporter.SendToSlack(logString)
 		}
 	},
 }))
@@ -189,7 +189,7 @@ const (
 	TagBytesReceived			= "bytesReceived"
 	TagRoute				= "route"
 	TagError                		= "error"
-	// DEPRECATED: Use TagReqHeader instead
+	// Deprecated: Use TagReqHeader instead
 	TagHeader               		= "header:"     // request header
 	TagReqHeader            		= "reqHeader:"  // request header
 	TagRespHeader           		= "respHeader:" // response header

middleware/logger/config.go

@@ -79,13 +79,15 @@ type Buffer interface {
 type LogFunc func(output Buffer, c *fiber.Ctx, data *Data, extraParam string) (int, error)
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:         nil,
 	Done:         nil,
 	Format:       "[${time}] ${status} - ${latency} ${method} ${path}\n",
 	TimeFormat:   "15:04:05",
 	TimeZone:     "Local",
-	TimeInterval: 500 * time.Millisecond,
+	TimeInterval: 500 * time.Millisecond, //nolint:gomnd // No magic number, just the default config
 	Output:       os.Stdout,
 	enableColors: true,
 }

middleware/logger/data.go

@@ -1,13 +1,10 @@
 package logger
 
 import (
-	"sync"
 	"sync/atomic"
 	"time"
 )
 
-var DataPool = sync.Pool{New: func() interface{} { return new(Data) }}
-
 // Data is a struct to define some variables to use in custom logger function.
 type Data struct {
 	Pid           string

middleware/logger/logger.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/mattn/go-colorable"
 	"github.com/mattn/go-isatty"
 	"github.com/valyala/bytebufferpool"
@@ -55,6 +56,8 @@ func New(config ...Config) fiber.Handler {
 		once       sync.Once
 		mu         sync.Mutex
 		errHandler fiber.ErrorHandler
+
+		dataPool = sync.Pool{New: func() interface{} { return new(Data) }}
 	)
 
 	// If colors are enabled, check terminal compatibility
@@ -75,7 +78,7 @@ func New(config ...Config) fiber.Handler {
 	}
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()
@@ -101,13 +104,13 @@ func New(config ...Config) fiber.Handler {
 		})
 
 		// Logger data
-		data := DataPool.Get().(*Data)
+		data := dataPool.Get().(*Data) //nolint:forcetypeassert,errcheck // We store nothing else in the pool
 		// no need for a reset, as long as we always override everything
 		data.Pid = pid
 		data.ErrPaddingStr = errPaddingStr
 		data.Timestamp = timestamp
 		// put data back in the pool
-		defer DataPool.Put(data)
+		defer dataPool.Put(data)
 
 		// Set latency start time
 		if cfg.enableLatency {
@@ -121,7 +124,7 @@ func New(config ...Config) fiber.Handler {
 		// Manually call error handler
 		if chainErr != nil {
 			if err := errHandler(c, chainErr); err != nil {
-				_ = c.SendStatus(fiber.StatusInternalServerError)
+				_ = c.SendStatus(fiber.StatusInternalServerError) //nolint:errcheck // TODO: Explain why we ignore the error here
 			}
 		}
 
@@ -142,18 +145,20 @@ func New(config ...Config) fiber.Handler {
 			}
 
 			// Format log to buffer
-			_, _ = buf.WriteString(fmt.Sprintf("%s |%s %3d %s| %7v | %15s |%s %-7s %s| %-"+errPaddingStr+"s %s\n",
-				timestamp.Load().(string),
-				statusColor(c.Response().StatusCode(), colors), c.Response().StatusCode(), colors.Reset,
-				data.Stop.Sub(data.Start).Round(time.Millisecond),
-				c.IP(),
-				methodColor(c.Method(), colors), c.Method(), colors.Reset,
-				c.Path(),
-				formatErr,
-			))
+			_, _ = buf.WriteString( //nolint:errcheck // This will never fail
+				fmt.Sprintf("%s |%s %3d %s| %7v | %15s |%s %-7s %s| %-"+errPaddingStr+"s %s\n",
+					timestamp.Load().(string),
+					statusColor(c.Response().StatusCode(), colors), c.Response().StatusCode(), colors.Reset,
+					data.Stop.Sub(data.Start).Round(time.Millisecond),
+					c.IP(),
+					methodColor(c.Method(), colors), c.Method(), colors.Reset,
+					c.Path(),
+					formatErr,
+				),
+			)
 
 			// Write buffer to output
-			_, _ = cfg.Output.Write(buf.Bytes())
+			_, _ = cfg.Output.Write(buf.Bytes()) //nolint:errcheck // This will never fail
 
 			if cfg.Done != nil {
 				cfg.Done(c, buf.Bytes())
@@ -169,7 +174,7 @@ func New(config ...Config) fiber.Handler {
 		// Loop over template parts execute dynamic parts and add fixed parts to the buffer
 		for i, logFunc := range logFunChain {
 			if logFunc == nil {
-				_, _ = buf.Write(templateChain[i])
+				_, _ = buf.Write(templateChain[i]) //nolint:errcheck // This will never fail
 			} else if templateChain[i] == nil {
 				_, err = logFunc(buf, c, data, "")
 			} else {
@@ -182,7 +187,7 @@ func New(config ...Config) fiber.Handler {
 
 		// Also write errors to the buffer
 		if err != nil {
-			_, _ = buf.WriteString(err.Error())
+			_, _ = buf.WriteString(err.Error()) //nolint:errcheck // This will never fail
 		}
 		mu.Lock()
 		// Write buffer to output
@@ -190,7 +195,7 @@ func New(config ...Config) fiber.Handler {
 			// Write error to output
 			if _, err := cfg.Output.Write([]byte(err.Error())); err != nil {
 				// There is something wrong with the given io.Writer
-				fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
+				_, _ = fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
 			}
 		}
 		mu.Unlock()

middleware/logger/logger_test.go

@@ -1,3 +1,4 @@
+//nolint:bodyclose // Much easier to just ignore memory leaks in tests
 package logger
 
 import (
@@ -16,6 +17,7 @@ import (
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/middleware/requestid"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/bytebufferpool"
 	"github.com/valyala/fasthttp"
 )
@@ -37,7 +39,7 @@ func Test_Logger(t *testing.T) {
 		return errors.New("some random error")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusInternalServerError, resp.StatusCode)
 	utils.AssertEqual(t, "some random error", buf.String())
@@ -70,21 +72,21 @@ func Test_Logger_locals(t *testing.T) {
 		return c.SendStatus(fiber.StatusOK)
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "johndoe", buf.String())
 
 	buf.Reset()
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/int", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/int", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "55", buf.String())
 
 	buf.Reset()
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/empty", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/empty", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "", buf.String())
@@ -100,7 +102,7 @@ func Test_Logger_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -113,15 +115,15 @@ func Test_Logger_Done(t *testing.T) {
 	app.Use(New(Config{
 		Done: func(c *fiber.Ctx, logString []byte) {
 			if c.Response().StatusCode() == fiber.StatusOK {
-				buf.Write(logString)
+				_, err := buf.Write(logString)
+				utils.AssertEqual(t, nil, err)
 			}
 		},
 	})).Get("/logging", func(ctx *fiber.Ctx) error {
 		return ctx.SendStatus(fiber.StatusOK)
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/logging", nil))
-
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/logging", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, true, buf.Len() > 0)
@@ -135,7 +137,7 @@ func Test_Logger_ErrorTimeZone(t *testing.T) {
 		TimeZone: "invalid",
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -156,7 +158,7 @@ func Test_Logger_ErrorOutput(t *testing.T) {
 		Output: o,
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 
@@ -178,7 +180,7 @@ func Test_Logger_All(t *testing.T) {
 	// Alias colors
 	colors := app.Config().ColorScheme
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/?foo=bar", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/?foo=bar", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 
@@ -198,7 +200,7 @@ func Test_Query_Params(t *testing.T) {
 		Output: buf,
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/?foo=bar&baz=moz", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/?foo=bar&baz=moz", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 
@@ -226,7 +228,7 @@ func Test_Response_Body(t *testing.T) {
 		return c.Send([]byte("Post in test"))
 	})
 
-	_, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 
 	expectedGetResponse := "Sample response body"
@@ -234,7 +236,7 @@ func Test_Response_Body(t *testing.T) {
 
 	buf.Reset() // Reset buffer to test POST
 
-	_, err = app.Test(httptest.NewRequest("POST", "/test", nil))
+	_, err = app.Test(httptest.NewRequest(fiber.MethodPost, "/test", nil))
 	utils.AssertEqual(t, nil, err)
 
 	expectedPostResponse := "Post in test"
@@ -258,7 +260,7 @@ func Test_Logger_AppendUint(t *testing.T) {
 		return c.SendString("hello")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "0 5 200", buf.String())
@@ -285,12 +287,11 @@ func Test_Logger_Data_Race(t *testing.T) {
 	wg := &sync.WaitGroup{}
 	wg.Add(1)
 	go func() {
-		resp1, err1 = app.Test(httptest.NewRequest("GET", "/", nil))
+		resp1, err1 = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 		wg.Done()
 	}()
-	resp2, err2 = app.Test(httptest.NewRequest("GET", "/", nil))
+	resp2, err2 = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	wg.Wait()
-
 	utils.AssertEqual(t, nil, err1)
 	utils.AssertEqual(t, fiber.StatusOK, resp1.StatusCode)
 	utils.AssertEqual(t, nil, err2)
@@ -299,21 +300,23 @@ func Test_Logger_Data_Race(t *testing.T) {
 
 // go test -v -run=^$ -bench=Benchmark_Logger -benchmem -count=4
 func Benchmark_Logger(b *testing.B) {
-	benchSetup := func(bb *testing.B, app *fiber.App) {
+	benchSetup := func(b *testing.B, app *fiber.App) {
+		b.Helper()
+
 		h := app.Handler()
 
 		fctx := &fasthttp.RequestCtx{}
-		fctx.Request.Header.SetMethod("GET")
+		fctx.Request.Header.SetMethod(fiber.MethodGet)
 		fctx.Request.SetRequestURI("/")
 
-		bb.ReportAllocs()
-		bb.ResetTimer()
+		b.ReportAllocs()
+		b.ResetTimer()
 
-		for n := 0; n < bb.N; n++ {
+		for n := 0; n < b.N; n++ {
 			h(fctx)
 		}
 
-		utils.AssertEqual(bb, 200, fctx.Response.Header.StatusCode())
+		utils.AssertEqual(b, 200, fctx.Response.Header.StatusCode())
 	}
 
 	b.Run("Base", func(bb *testing.B) {
@@ -375,8 +378,7 @@ func Test_Response_Header(t *testing.T) {
 		return c.SendString("Hello fiber!")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
-
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "Hello fiber!", buf.String())
@@ -396,10 +398,10 @@ func Test_Req_Header(t *testing.T) {
 	app.Get("/", func(c *fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
 	})
-	headerReq := httptest.NewRequest("GET", "/", nil)
+	headerReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	headerReq.Header.Add("test", "Hello fiber!")
-	resp, err := app.Test(headerReq)
 
+	resp, err := app.Test(headerReq)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "Hello fiber!", buf.String())
@@ -419,10 +421,10 @@ func Test_ReqHeader_Header(t *testing.T) {
 	app.Get("/", func(c *fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
 	})
-	reqHeaderReq := httptest.NewRequest("GET", "/", nil)
+	reqHeaderReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	reqHeaderReq.Header.Add("test", "Hello fiber!")
-	resp, err := app.Test(reqHeaderReq)
 
+	resp, err := app.Test(reqHeaderReq)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "Hello fiber!", buf.String())
@@ -449,10 +451,10 @@ func Test_CustomTags(t *testing.T) {
 	app.Get("/", func(c *fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
 	})
-	reqHeaderReq := httptest.NewRequest("GET", "/", nil)
+	reqHeaderReq := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	reqHeaderReq.Header.Add("test", "Hello fiber!")
-	resp, err := app.Test(reqHeaderReq)
 
+	resp, err := app.Test(reqHeaderReq)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, customTag, buf.String())
@@ -492,7 +494,7 @@ func Test_Logger_ByteSent_Streaming(t *testing.T) {
 		return nil
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 	utils.AssertEqual(t, "0 0 200", buf.String())

middleware/logger/tags.go

@@ -31,7 +31,7 @@ const (
 	TagBytesReceived     = "bytesReceived"
 	TagRoute             = "route"
 	TagError             = "error"
-	// DEPRECATED: Use TagReqHeader instead
+	// Deprecated: Use TagReqHeader instead
 	TagHeader     = "header:"
 	TagReqHeader  = "reqHeader:"
 	TagRespHeader = "respHeader:"
@@ -195,7 +195,7 @@ func createTagMap(cfg *Config) map[string]LogFunc {
 			return output.WriteString(fmt.Sprintf("%7v", latency))
 		},
 		TagTime: func(output Buffer, c *fiber.Ctx, data *Data, extraParam string) (int, error) {
-			return output.WriteString(data.Timestamp.Load().(string))
+			return output.WriteString(data.Timestamp.Load().(string)) //nolint:forcetypeassert // We always store a string in here
 		},
 	}
 	// merge with custom tags from user

middleware/logger/template_chain.go

@@ -14,13 +14,16 @@ import (
 // funcChain contains for the parts which exist the functions for the dynamic parts
 // funcChain and fixParts always have the same length and contain nil for the parts where no data is required in the chain,
 // if a function exists for the part, a parameter for it can also exist in the fixParts slice
-func buildLogFuncChain(cfg *Config, tagFunctions map[string]LogFunc) (fixParts [][]byte, funcChain []LogFunc, err error) {
+func buildLogFuncChain(cfg *Config, tagFunctions map[string]LogFunc) ([][]byte, []LogFunc, error) {
 	// process flow is copied from the fasttemplate flow https://github.com/valyala/fasttemplate/blob/2a2d1afadadf9715bfa19683cdaeac8347e5d9f9/template.go#L23-L62
 	templateB := utils.UnsafeBytes(cfg.Format)
 	startTagB := utils.UnsafeBytes(startTag)
 	endTagB := utils.UnsafeBytes(endTag)
 	paramSeparatorB := utils.UnsafeBytes(paramSeparator)
 
+	var fixParts [][]byte
+	var funcChain []LogFunc
+
 	for {
 		currentPos := bytes.Index(templateB, startTagB)
 		if currentPos < 0 {
@@ -42,13 +45,13 @@ func buildLogFuncChain(cfg *Config, tagFunctions map[string]LogFunc) (fixParts [
 		// ## function block ##
 		// first check for tags with parameters
 		if index := bytes.Index(templateB[:currentPos], paramSeparatorB); index != -1 {
-			if logFunc, ok := tagFunctions[utils.UnsafeString(templateB[:index+1])]; ok {
-				funcChain = append(funcChain, logFunc)
-				// add param to the fixParts
-				fixParts = append(fixParts, templateB[index+1:currentPos])
-			} else {
+			logFunc, ok := tagFunctions[utils.UnsafeString(templateB[:index+1])]
+			if !ok {
 				return nil, nil, errors.New("No parameter found in \"" + utils.UnsafeString(templateB[:currentPos]) + "\"")
 			}
+			funcChain = append(funcChain, logFunc)
+			// add param to the fixParts
+			fixParts = append(fixParts, templateB[index+1:currentPos])
 		} else if logFunc, ok := tagFunctions[utils.UnsafeString(templateB[:currentPos])]; ok {
 			// add functions without parameter
 			funcChain = append(funcChain, logFunc)
@@ -63,5 +66,5 @@ func buildLogFuncChain(cfg *Config, tagFunctions map[string]LogFunc) (fixParts [
 	funcChain = append(funcChain, nil)
 	fixParts = append(fixParts, templateB)
 
-	return
+	return fixParts, funcChain, nil
 }

middleware/monitor/config.go

@@ -41,36 +41,48 @@ type Config struct {
 	// ChartJsURL for specify ChartJS library  path or URL . also you can use relative path
 	//
 	// Optional. Default: https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js
-	ChartJsURL string
+	ChartJSURL string
 
 	index string
 }
 
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Title:      defaultTitle,
 	Refresh:    defaultRefresh,
 	FontURL:    defaultFontURL,
-	ChartJsURL: defaultChartJsURL,
+	ChartJSURL: defaultChartJSURL,
 	CustomHead: defaultCustomHead,
 	APIOnly:    false,
 	Next:       nil,
-	index: newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL,
-		defaultCustomHead}),
+	index: newIndex(viewBag{
+		defaultTitle,
+		defaultRefresh,
+		defaultFontURL,
+		defaultChartJSURL,
+		defaultCustomHead,
+	}),
 }
 
 func configDefault(config ...Config) Config {
 	// Users can change ConfigDefault.Title/Refresh which then
 	// become incompatible with ConfigDefault.index
-	if ConfigDefault.Title != defaultTitle || ConfigDefault.Refresh != defaultRefresh ||
-		ConfigDefault.FontURL != defaultFontURL || ConfigDefault.ChartJsURL != defaultChartJsURL ||
+	if ConfigDefault.Title != defaultTitle ||
+		ConfigDefault.Refresh != defaultRefresh ||
+		ConfigDefault.FontURL != defaultFontURL ||
+		ConfigDefault.ChartJSURL != defaultChartJSURL ||
 		ConfigDefault.CustomHead != defaultCustomHead {
-
 		if ConfigDefault.Refresh < minRefresh {
 			ConfigDefault.Refresh = minRefresh
 		}
 		// update default index with new default title/refresh
-		ConfigDefault.index = newIndex(viewBag{ConfigDefault.Title,
-			ConfigDefault.Refresh, ConfigDefault.FontURL, ConfigDefault.ChartJsURL, ConfigDefault.CustomHead})
+		ConfigDefault.index = newIndex(viewBag{
+			ConfigDefault.Title,
+			ConfigDefault.Refresh,
+			ConfigDefault.FontURL,
+			ConfigDefault.ChartJSURL,
+			ConfigDefault.CustomHead,
+		})
 	}
 
 	// Return default config if nothing provided
@@ -93,8 +105,8 @@ func configDefault(config ...Config) Config {
 		cfg.FontURL = defaultFontURL
 	}
 
-	if cfg.ChartJsURL == "" {
-		cfg.ChartJsURL = defaultChartJsURL
+	if cfg.ChartJSURL == "" {
+		cfg.ChartJSURL = defaultChartJSURL
 	}
 	if cfg.Refresh < minRefresh {
 		cfg.Refresh = minRefresh
@@ -112,8 +124,8 @@ func configDefault(config ...Config) Config {
 	cfg.index = newIndex(viewBag{
 		title:      cfg.Title,
 		refresh:    cfg.Refresh,
-		fontUrl:    cfg.FontURL,
-		chartJsUrl: cfg.ChartJsURL,
+		fontURL:    cfg.FontURL,
+		chartJSURL: cfg.ChartJSURL,
 		customHead: cfg.CustomHead,
 	})
 

middleware/monitor/config_test.go

@@ -18,11 +18,11 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set title", func(t *testing.T) {
@@ -35,11 +35,11 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, title, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{title, defaultRefresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{title, defaultRefresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set refresh less than default", func(t *testing.T) {
@@ -51,11 +51,11 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, minRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, minRefresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, minRefresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set refresh", func(t *testing.T) {
@@ -68,45 +68,45 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, refresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, refresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, refresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set font url", func(t *testing.T) {
 		t.Parallel()
-		fontUrl := "https://example.com"
+		fontURL := "https://example.com"
 		cfg := configDefault(Config{
-			FontURL: fontUrl,
+			FontURL: fontURL,
 		})
 
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
-		utils.AssertEqual(t, fontUrl, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, fontURL, cfg.FontURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, fontUrl, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, fontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set chart js url", func(t *testing.T) {
 		t.Parallel()
-		chartUrl := "http://example.com"
+		chartURL := "http://example.com"
 		cfg := configDefault(Config{
-			ChartJsURL: chartUrl,
+			ChartJSURL: chartURL,
 		})
 
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, chartUrl, cfg.ChartJsURL)
+		utils.AssertEqual(t, chartURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, chartUrl, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, chartURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set custom head", func(t *testing.T) {
@@ -119,11 +119,11 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, head, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL, head}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJSURL, head}), cfg.index)
 	})
 
 	t.Run("set api only", func(t *testing.T) {
@@ -135,11 +135,11 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, true, cfg.APIOnly)
 		utils.AssertEqual(t, (func(*fiber.Ctx) bool)(nil), cfg.Next)
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 
 	t.Run("set next", func(t *testing.T) {
@@ -154,10 +154,10 @@ func Test_Config_Default(t *testing.T) {
 		utils.AssertEqual(t, defaultTitle, cfg.Title)
 		utils.AssertEqual(t, defaultRefresh, cfg.Refresh)
 		utils.AssertEqual(t, defaultFontURL, cfg.FontURL)
-		utils.AssertEqual(t, defaultChartJsURL, cfg.ChartJsURL)
+		utils.AssertEqual(t, defaultChartJSURL, cfg.ChartJSURL)
 		utils.AssertEqual(t, defaultCustomHead, cfg.CustomHead)
 		utils.AssertEqual(t, false, cfg.APIOnly)
 		utils.AssertEqual(t, f(nil), cfg.Next(nil))
-		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL, defaultCustomHead}), cfg.index)
+		utils.AssertEqual(t, newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJSURL, defaultCustomHead}), cfg.index)
 	})
 }

middleware/monitor/index.go

@@ -9,23 +9,22 @@ import (
 type viewBag struct {
 	title      string
 	refresh    time.Duration
-	fontUrl    string
-	chartJsUrl string
+	fontURL    string
+	chartJSURL string
 	customHead string
 }
 
 // returns index with new title/refresh
 func newIndex(dat viewBag) string {
-
 	timeout := dat.refresh.Milliseconds() - timeoutDiff
 	if timeout < timeoutDiff {
 		timeout = timeoutDiff
 	}
 	ts := strconv.FormatInt(timeout, 10)
 	replacer := strings.NewReplacer("$TITLE", dat.title, "$TIMEOUT", ts,
-		"$FONT_URL", dat.fontUrl, "$CHART_JS_URL", dat.chartJsUrl, "$CUSTOM_HEAD", dat.customHead,
+		"$FONT_URL", dat.fontURL, "$CHART_JS_URL", dat.chartJSURL, "$CUSTOM_HEAD", dat.customHead,
 	)
-	return replacer.Replace(indexHtml)
+	return replacer.Replace(indexHTML)
 }
 
 const (
@@ -35,11 +34,11 @@ const (
 	timeoutDiff       = 200 // timeout will be Refresh (in milliseconds) - timeoutDiff
 	minRefresh        = timeoutDiff * time.Millisecond
 	defaultFontURL    = `https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap`
-	defaultChartJsURL = `https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js`
+	defaultChartJSURL = `https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js`
 	defaultCustomHead = ``
 
 	// parametrized by $TITLE and $TIMEOUT
-	indexHtml = `<!DOCTYPE html>
+	indexHTML = `<!DOCTYPE html>
 <html lang="en">
 <head>
 	<meta charset="UTF-8">

middleware/monitor/monitor.go

@@ -33,18 +33,20 @@ type statsOS struct {
 	Conns    int     `json:"conns"`
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var (
-	monitPidCpu   atomic.Value
-	monitPidRam   atomic.Value
-	monitPidConns atomic.Value
+	monitPIDCPU   atomic.Value
+	monitPIDRAM   atomic.Value
+	monitPIDConns atomic.Value
 
-	monitOsCpu      atomic.Value
-	monitOsRam      atomic.Value
-	monitOsTotalRam atomic.Value
-	monitOsLoadAvg  atomic.Value
-	monitOsConns    atomic.Value
+	monitOSCPU      atomic.Value
+	monitOSRAM      atomic.Value
+	monitOSTotalRAM atomic.Value
+	monitOSLoadAvg  atomic.Value
+	monitOSConns    atomic.Value
 )
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var (
 	mutex sync.RWMutex
 	once  sync.Once
@@ -58,7 +60,7 @@ func New(config ...Config) fiber.Handler {
 
 	// Start routine to update statistics
 	once.Do(func() {
-		p, _ := process.NewProcess(int32(os.Getpid()))
+		p, _ := process.NewProcess(int32(os.Getpid())) //nolint:errcheck // TODO: Handle error
 
 		updateStatistics(p)
 
@@ -72,6 +74,7 @@ func New(config ...Config) fiber.Handler {
 	})
 
 	// Return new handler
+	//nolint:errcheck // Ignore the type-assertion errors
 	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
@@ -83,15 +86,15 @@ func New(config ...Config) fiber.Handler {
 		}
 		if c.Get(fiber.HeaderAccept) == fiber.MIMEApplicationJSON || cfg.APIOnly {
 			mutex.Lock()
-			data.PID.CPU = monitPidCpu.Load().(float64)
-			data.PID.RAM = monitPidRam.Load().(uint64)
-			data.PID.Conns = monitPidConns.Load().(int)
+			data.PID.CPU, _ = monitPIDCPU.Load().(float64)
+			data.PID.RAM, _ = monitPIDRAM.Load().(uint64)
+			data.PID.Conns, _ = monitPIDConns.Load().(int)
 
-			data.OS.CPU = monitOsCpu.Load().(float64)
-			data.OS.RAM = monitOsRam.Load().(uint64)
-			data.OS.TotalRAM = monitOsTotalRam.Load().(uint64)
-			data.OS.LoadAvg = monitOsLoadAvg.Load().(float64)
-			data.OS.Conns = monitOsConns.Load().(int)
+			data.OS.CPU, _ = monitOSCPU.Load().(float64)
+			data.OS.RAM, _ = monitOSRAM.Load().(uint64)
+			data.OS.TotalRAM, _ = monitOSTotalRAM.Load().(uint64)
+			data.OS.LoadAvg, _ = monitOSLoadAvg.Load().(float64)
+			data.OS.Conns, _ = monitOSConns.Load().(int)
 			mutex.Unlock()
 			return c.Status(fiber.StatusOK).JSON(data)
 		}
@@ -101,29 +104,35 @@ func New(config ...Config) fiber.Handler {
 }
 
 func updateStatistics(p *process.Process) {
-	pidCpu, _ := p.CPUPercent()
-	monitPidCpu.Store(pidCpu / 10)
-
-	if osCpu, _ := cpu.Percent(0, false); len(osCpu) > 0 {
-		monitOsCpu.Store(osCpu[0])
+	pidCPU, err := p.CPUPercent()
+	if err != nil {
+		monitPIDCPU.Store(pidCPU / 10) //nolint:gomnd // TODO: Explain why we divide by 10 here
 	}
 
-	if pidMem, _ := p.MemoryInfo(); pidMem != nil {
-		monitPidRam.Store(pidMem.RSS)
+	if osCPU, err := cpu.Percent(0, false); err != nil && len(osCPU) > 0 {
+		monitOSCPU.Store(osCPU[0])
 	}
 
-	if osMem, _ := mem.VirtualMemory(); osMem != nil {
-		monitOsRam.Store(osMem.Used)
-		monitOsTotalRam.Store(osMem.Total)
+	if pidRAM, err := p.MemoryInfo(); err != nil && pidRAM != nil {
+		monitPIDRAM.Store(pidRAM.RSS)
 	}
 
-	if loadAvg, _ := load.Avg(); loadAvg != nil {
-		monitOsLoadAvg.Store(loadAvg.Load1)
+	if osRAM, err := mem.VirtualMemory(); err != nil && osRAM != nil {
+		monitOSRAM.Store(osRAM.Used)
+		monitOSTotalRAM.Store(osRAM.Total)
 	}
 
-	pidConns, _ := net.ConnectionsPid("tcp", p.Pid)
-	monitPidConns.Store(len(pidConns))
+	if loadAvg, err := load.Avg(); err != nil && loadAvg != nil {
+		monitOSLoadAvg.Store(loadAvg.Load1)
+	}
 
-	osConns, _ := net.Connections("tcp")
-	monitOsConns.Store(len(osConns))
+	pidConns, err := net.ConnectionsPid("tcp", p.Pid)
+	if err != nil {
+		monitPIDConns.Store(len(pidConns))
+	}
+
+	osConns, err := net.Connections("tcp")
+	if err != nil {
+		monitOSConns.Store(len(osConns))
+	}
 }

middleware/monitor/monitor_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -61,6 +62,7 @@ func Test_Monitor_Html(t *testing.T) {
 		conf.Refresh.Milliseconds()-timeoutDiff)
 	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(timeoutLine)))
 }
+
 func Test_Monitor_Html_CustomCodes(t *testing.T) {
 	t.Parallel()
 
@@ -82,8 +84,10 @@ func Test_Monitor_Html_CustomCodes(t *testing.T) {
 	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(timeoutLine)))
 
 	// custom config
-	conf := Config{Title: "New " + defaultTitle, Refresh: defaultRefresh + time.Second,
-		ChartJsURL: "https://cdnjs.com/libraries/Chart.js",
+	conf := Config{
+		Title:      "New " + defaultTitle,
+		Refresh:    defaultRefresh + time.Second,
+		ChartJSURL: "https://cdnjs.com/libraries/Chart.js",
 		FontURL:    "/public/my-font.css",
 		CustomHead: `<style>body{background:#fff}</style>`,
 	}
@@ -136,7 +140,7 @@ func Benchmark_Monitor(b *testing.B) {
 	h := app.Handler()
 
 	fctx := &fasthttp.RequestCtx{}
-	fctx.Request.Header.SetMethod("GET")
+	fctx.Request.Header.SetMethod(fiber.MethodGet)
 	fctx.Request.SetRequestURI("/")
 	fctx.Request.Header.Set(fiber.HeaderAccept, fiber.MIMEApplicationJSON)
 

middleware/pprof/config.go

@@ -1,6 +1,8 @@
 package pprof
 
-import "github.com/gofiber/fiber/v2"
+import (
+	"github.com/gofiber/fiber/v2"
+)
 
 // Config defines the config for middleware.
 type Config struct {
@@ -17,6 +19,7 @@ type Config struct {
 	Prefix string
 }
 
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next: nil,
 }

middleware/pprof/pprof.go

@@ -5,22 +5,8 @@ import (
 	"strings"
 
 	"github.com/gofiber/fiber/v2"
-	"github.com/valyala/fasthttp/fasthttpadaptor"
-)
 
-// Set pprof adaptors
-var (
-	pprofIndex        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Index)
-	pprofCmdline      = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Cmdline)
-	pprofProfile      = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Profile)
-	pprofSymbol       = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Symbol)
-	pprofTrace        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Trace)
-	pprofAllocs       = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("allocs").ServeHTTP)
-	pprofBlock        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("block").ServeHTTP)
-	pprofGoroutine    = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("goroutine").ServeHTTP)
-	pprofHeap         = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("heap").ServeHTTP)
-	pprofMutex        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("mutex").ServeHTTP)
-	pprofThreadcreate = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("threadcreate").ServeHTTP)
+	"github.com/valyala/fasthttp/fasthttpadaptor"
 )
 
 // New creates a new middleware handler
@@ -28,6 +14,21 @@ func New(config ...Config) fiber.Handler {
 	// Set default config
 	cfg := configDefault(config...)
 
+	// Set pprof adaptors
+	var (
+		pprofIndex        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Index)
+		pprofCmdline      = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Cmdline)
+		pprofProfile      = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Profile)
+		pprofSymbol       = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Symbol)
+		pprofTrace        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Trace)
+		pprofAllocs       = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("allocs").ServeHTTP)
+		pprofBlock        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("block").ServeHTTP)
+		pprofGoroutine    = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("goroutine").ServeHTTP)
+		pprofHeap         = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("heap").ServeHTTP)
+		pprofMutex        = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("mutex").ServeHTTP)
+		pprofThreadcreate = fasthttpadaptor.NewFastHTTPHandlerFunc(pprof.Handler("threadcreate").ServeHTTP)
+	)
+
 	// Return new handler
 	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true

middleware/proxy/config.go

@@ -5,6 +5,7 @@ import (
 	"time"
 
 	"github.com/gofiber/fiber/v2"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -48,7 +49,7 @@ type Config struct {
 	WriteBufferSize int
 
 	// tls config for the http client.
-	TlsConfig *tls.Config
+	TlsConfig *tls.Config //nolint:stylecheck,revive // TODO: Rename to "TLSConfig" in v3
 
 	// Client is custom client when client config is complex.
 	// Note that Servers, Timeout, WriteBufferSize, ReadBufferSize and TlsConfig
@@ -57,6 +58,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:           nil,
 	ModifyRequest:  nil,

middleware/proxy/proxy.go

@@ -3,19 +3,20 @@ package proxy
 import (
 	"bytes"
 	"crypto/tls"
-	"fmt"
+	"log"
 	"net/url"
 	"strings"
 	"sync"
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
 // New is deprecated
 func New(config Config) fiber.Handler {
-	fmt.Println("proxy.New is deprecated, please use proxy.Balancer instead")
+	log.Printf("proxy.New is deprecated, please use proxy.Balancer instead\n")
 	return Balancer(config)
 }
 
@@ -25,7 +26,7 @@ func Balancer(config Config) fiber.Handler {
 	cfg := configDefault(config)
 
 	// Load balanced client
-	var lbc = &fasthttp.LBClient{}
+	lbc := &fasthttp.LBClient{}
 	// Note that Servers, Timeout, WriteBufferSize, ReadBufferSize and TlsConfig
 	// will not be used if the client are set.
 	if config.Client == nil {
@@ -61,7 +62,7 @@ func Balancer(config Config) fiber.Handler {
 	}
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) error {
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()
@@ -76,7 +77,7 @@ func Balancer(config Config) fiber.Handler {
 
 		// Modify request
 		if cfg.ModifyRequest != nil {
-			if err = cfg.ModifyRequest(c); err != nil {
+			if err := cfg.ModifyRequest(c); err != nil {
 				return err
 			}
 		}
@@ -84,7 +85,7 @@ func Balancer(config Config) fiber.Handler {
 		req.SetRequestURI(utils.UnsafeString(req.RequestURI()))
 
 		// Forward request
-		if err = lbc.Do(req, res); err != nil {
+		if err := lbc.Do(req, res); err != nil {
 			return err
 		}
 
@@ -93,7 +94,7 @@ func Balancer(config Config) fiber.Handler {
 
 		// Modify response
 		if cfg.ModifyResponse != nil {
-			if err = cfg.ModifyResponse(c); err != nil {
+			if err := cfg.ModifyResponse(c); err != nil {
 				return err
 			}
 		}
@@ -103,16 +104,20 @@ func Balancer(config Config) fiber.Handler {
 	}
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var client = &fasthttp.Client{
 	NoDefaultUserAgentHeader: true,
 	DisablePathNormalizing:   true,
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var lock sync.RWMutex
 
 // WithTlsConfig update http client with a user specified tls.config
 // This function should be called before Do and Forward.
 // Deprecated: use WithClient instead.
+//
+//nolint:stylecheck,revive // TODO: Rename to "WithTLSConfig" in v3
 func WithTlsConfig(tlsConfig *tls.Config) {
 	client.TLSConfig = tlsConfig
 }

middleware/proxy/proxy_test.go

@@ -4,7 +4,6 @@ import (
 	"crypto/tls"
 	"io"
 	"net"
-	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
@@ -13,10 +12,11 @@ import (
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/internal/tlstest"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
-func createProxyTestServer(handler fiber.Handler, t *testing.T) (*fiber.App, string) {
+func createProxyTestServer(t *testing.T, handler fiber.Handler) (*fiber.App, string) {
 	t.Helper()
 
 	target := fiber.New(fiber.Config{DisableStartupMessage: true})
@@ -60,7 +60,7 @@ func Test_Proxy_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -69,11 +69,11 @@ func Test_Proxy_Next(t *testing.T) {
 func Test_Proxy(t *testing.T) {
 	t.Parallel()
 
-	target, addr := createProxyTestServer(
-		func(c *fiber.Ctx) error { return c.SendStatus(fiber.StatusTeapot) }, t,
-	)
+	target, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
+		return c.SendStatus(fiber.StatusTeapot)
+	})
 
-	resp, err := target.Test(httptest.NewRequest("GET", "/", nil), 2000)
+	resp, err := target.Test(httptest.NewRequest(fiber.MethodGet, "/", nil), 2000)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusTeapot, resp.StatusCode)
 
@@ -81,7 +81,7 @@ func Test_Proxy(t *testing.T) {
 
 	app.Use(Balancer(Config{Servers: []string{addr}}))
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Host = addr
 	resp, err = app.Test(req)
 	utils.AssertEqual(t, nil, err)
@@ -107,7 +107,7 @@ func Test_Proxy_Balancer_WithTlsConfig(t *testing.T) {
 	})
 
 	addr := ln.Addr().String()
-	clientTLSConf := &tls.Config{InsecureSkipVerify: true}
+	clientTLSConf := &tls.Config{InsecureSkipVerify: true} //nolint:gosec // We're in a test func, so this is fine
 
 	// disable certificate verification in Balancer
 	app.Use(Balancer(Config{
@@ -128,9 +128,9 @@ func Test_Proxy_Balancer_WithTlsConfig(t *testing.T) {
 func Test_Proxy_Forward_WithTlsConfig_To_Http(t *testing.T) {
 	t.Parallel()
 
-	_, targetAddr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, targetAddr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		return c.SendString("hello from target")
-	}, t)
+	})
 
 	proxyServerTLSConf, _, err := tlstest.GetTLSConfigs()
 	utils.AssertEqual(t, nil, err)
@@ -164,13 +164,13 @@ func Test_Proxy_Forward(t *testing.T) {
 
 	app := fiber.New()
 
-	_, addr := createProxyTestServer(
-		func(c *fiber.Ctx) error { return c.SendString("forwarded") }, t,
-	)
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
+		return c.SendString("forwarded")
+	})
 
 	app.Use(Forward("http://" + addr))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -198,7 +198,7 @@ func Test_Proxy_Forward_WithTlsConfig(t *testing.T) {
 	})
 
 	addr := ln.Addr().String()
-	clientTLSConf := &tls.Config{InsecureSkipVerify: true}
+	clientTLSConf := &tls.Config{InsecureSkipVerify: true} //nolint:gosec // We're in a test func, so this is fine
 
 	// disable certificate verification
 	WithTlsConfig(clientTLSConf)
@@ -217,9 +217,9 @@ func Test_Proxy_Forward_WithTlsConfig(t *testing.T) {
 func Test_Proxy_Modify_Response(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		return c.Status(500).SendString("not modified")
-	}, t)
+	})
 
 	app := fiber.New()
 	app.Use(Balancer(Config{
@@ -230,7 +230,7 @@ func Test_Proxy_Modify_Response(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -243,10 +243,10 @@ func Test_Proxy_Modify_Response(t *testing.T) {
 func Test_Proxy_Modify_Request(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		b := c.Request().Body()
 		return c.SendString(string(b))
-	}, t)
+	})
 
 	app := fiber.New()
 	app.Use(Balancer(Config{
@@ -257,7 +257,7 @@ func Test_Proxy_Modify_Request(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -270,10 +270,10 @@ func Test_Proxy_Modify_Request(t *testing.T) {
 func Test_Proxy_Timeout_Slow_Server(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		time.Sleep(2 * time.Second)
 		return c.SendString("fiber is awesome")
-	}, t)
+	})
 
 	app := fiber.New()
 	app.Use(Balancer(Config{
@@ -281,7 +281,7 @@ func Test_Proxy_Timeout_Slow_Server(t *testing.T) {
 		Timeout: 3 * time.Second,
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil), 5000)
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil), 5000)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
@@ -294,10 +294,10 @@ func Test_Proxy_Timeout_Slow_Server(t *testing.T) {
 func Test_Proxy_With_Timeout(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		time.Sleep(1 * time.Second)
 		return c.SendString("fiber is awesome")
-	}, t)
+	})
 
 	app := fiber.New()
 	app.Use(Balancer(Config{
@@ -305,7 +305,7 @@ func Test_Proxy_With_Timeout(t *testing.T) {
 		Timeout: 100 * time.Millisecond,
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil), 2000)
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil), 2000)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusInternalServerError, resp.StatusCode)
 
@@ -318,16 +318,16 @@ func Test_Proxy_With_Timeout(t *testing.T) {
 func Test_Proxy_Buffer_Size_Response(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		long := strings.Join(make([]string, 5000), "-")
 		c.Set("Very-Long-Header", long)
 		return c.SendString("ok")
-	}, t)
+	})
 
 	app := fiber.New()
 	app.Use(Balancer(Config{Servers: []string{addr}}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusInternalServerError, resp.StatusCode)
 
@@ -337,7 +337,7 @@ func Test_Proxy_Buffer_Size_Response(t *testing.T) {
 		ReadBufferSize: 1024 * 8,
 	}))
 
-	resp, err = app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 }
@@ -357,9 +357,9 @@ func Test_Proxy_Do_RestoreOriginalURL(t *testing.T) {
 		utils.AssertEqual(t, originalURL, c.OriginalURL())
 		return c.SendString("ok")
 	})
-	_, err1 := app.Test(httptest.NewRequest("GET", "/test", nil))
+	_, err1 := app.Test(httptest.NewRequest(fiber.MethodGet, "/test", nil))
 	// This test requires multiple requests due to zero allocation used in fiber
-	_, err2 := app.Test(httptest.NewRequest("GET", "/test", nil))
+	_, err2 := app.Test(httptest.NewRequest(fiber.MethodGet, "/test", nil))
 
 	utils.AssertEqual(t, nil, err1)
 	utils.AssertEqual(t, nil, err2)
@@ -369,9 +369,9 @@ func Test_Proxy_Do_RestoreOriginalURL(t *testing.T) {
 func Test_Proxy_Do_HTTP_Prefix_URL(t *testing.T) {
 	t.Parallel()
 
-	_, addr := createProxyTestServer(func(c *fiber.Ctx) error {
+	_, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
 		return c.SendString("hello world")
-	}, t)
+	})
 
 	app := fiber.New(fiber.Config{DisableStartupMessage: true})
 	app.Get("/*", func(c *fiber.Ctx) error {
@@ -386,7 +386,7 @@ func Test_Proxy_Do_HTTP_Prefix_URL(t *testing.T) {
 		return nil
 	})
 
-	resp, err := app.Test(httptest.NewRequest(http.MethodGet, "/http://"+addr, nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/http://"+addr, nil))
 	utils.AssertEqual(t, nil, err)
 	s, err := io.ReadAll(resp.Body)
 	utils.AssertEqual(t, nil, err)
@@ -431,9 +431,8 @@ func Test_Proxy_Forward_Local_Client(t *testing.T) {
 	app.Use(Forward("http://"+addr+"/test_local_client", &fasthttp.Client{
 		NoDefaultUserAgentHeader: true,
 		DisablePathNormalizing:   true,
-		Dial: func(addr string) (net.Conn, error) {
-			return fasthttp.Dial(addr)
-		},
+
+		Dial: fasthttp.Dial,
 	}))
 	go func() { utils.AssertEqual(t, nil, app.Listener(ln)) }()
 
@@ -447,11 +446,11 @@ func Test_Proxy_Forward_Local_Client(t *testing.T) {
 func Test_ProxyBalancer_Custom_Client(t *testing.T) {
 	t.Parallel()
 
-	target, addr := createProxyTestServer(
-		func(c *fiber.Ctx) error { return c.SendStatus(fiber.StatusTeapot) }, t,
-	)
+	target, addr := createProxyTestServer(t, func(c *fiber.Ctx) error {
+		return c.SendStatus(fiber.StatusTeapot)
+	})
 
-	resp, err := target.Test(httptest.NewRequest("GET", "/", nil), 2000)
+	resp, err := target.Test(httptest.NewRequest(fiber.MethodGet, "/", nil), 2000)
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusTeapot, resp.StatusCode)
 
@@ -468,7 +467,7 @@ func Test_ProxyBalancer_Custom_Client(t *testing.T) {
 		Timeout: time.Second,
 	}}))
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Host = addr
 	resp, err = app.Test(req)
 	utils.AssertEqual(t, nil, err)

middleware/recover/config.go

@@ -1,4 +1,4 @@
-package recover
+package recover //nolint:predeclared // TODO: Rename to some non-builtin
 
 import (
 	"github.com/gofiber/fiber/v2"
@@ -23,6 +23,8 @@ type Config struct {
 }
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:              nil,
 	EnableStackTrace:  false,

middleware/recover/recover.go

@@ -1,4 +1,4 @@
-package recover
+package recover //nolint:predeclared // TODO: Rename to some non-builtin
 
 import (
 	"fmt"
@@ -9,7 +9,7 @@ import (
 )
 
 func defaultStackTraceHandler(_ *fiber.Ctx, e interface{}) {
-	_, _ = os.Stderr.WriteString(fmt.Sprintf("panic: %v\n%s\n", e, debug.Stack()))
+	_, _ = os.Stderr.WriteString(fmt.Sprintf("panic: %v\n%s\n", e, debug.Stack())) //nolint:errcheck // This will never fail
 }
 
 // New creates a new middleware handler
@@ -18,7 +18,7 @@ func New(config ...Config) fiber.Handler {
 	cfg := configDefault(config...)
 
 	// Return new handler
-	return func(c *fiber.Ctx) (err error) {
+	return func(c *fiber.Ctx) (err error) { //nolint:nonamedreturns // Uses recover() to overwrite the error
 		// Don't execute middleware if Next returns true
 		if cfg.Next != nil && cfg.Next(c) {
 			return c.Next()

middleware/recover/recover_test.go

@@ -1,4 +1,4 @@
-package recover
+package recover //nolint:predeclared // TODO: Rename to some non-builtin
 
 import (
 	"net/http/httptest"
@@ -24,7 +24,7 @@ func Test_Recover(t *testing.T) {
 		panic("Hi, I'm an error!")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/panic", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/panic", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusTeapot, resp.StatusCode)
 }
@@ -39,7 +39,7 @@ func Test_Recover_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
 }
@@ -55,7 +55,7 @@ func Test_Recover_EnableStackTrace(t *testing.T) {
 		panic("Hi, I'm an error!")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/panic", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/panic", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusInternalServerError, resp.StatusCode)
 }

middleware/requestid/config.go

@@ -33,6 +33,8 @@ type Config struct {
 // It uses a fast UUID generator which will expose the number of
 // requests made to the server. To conceal this value for better
 // privacy, use the "utils.UUIDv4" generator.
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
 	Next:       nil,
 	Header:     fiber.HeaderXRequestID,

middleware/requestid/requestid_test.go

@@ -19,14 +19,14 @@ func Test_RequestID(t *testing.T) {
 		return c.SendString("Hello, World 👋!")
 	})
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 
 	reqid := resp.Header.Get(fiber.HeaderXRequestID)
 	utils.AssertEqual(t, 36, len(reqid))
 
-	req := httptest.NewRequest("GET", "/", nil)
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
 	req.Header.Add(fiber.HeaderXRequestID, reqid)
 
 	resp, err = app.Test(req)
@@ -45,7 +45,7 @@ func Test_RequestID_Next(t *testing.T) {
 		},
 	}))
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, resp.Header.Get(fiber.HeaderXRequestID), "")
 	utils.AssertEqual(t, fiber.StatusNotFound, resp.StatusCode)
@@ -54,13 +54,13 @@ func Test_RequestID_Next(t *testing.T) {
 // go test -run Test_RequestID_Locals
 func Test_RequestID_Locals(t *testing.T) {
 	t.Parallel()
-	reqId := "ThisIsARequestId"
+	reqID := "ThisIsARequestId"
 	ctxKey := "ThisIsAContextKey"
 
 	app := fiber.New()
 	app.Use(New(Config{
 		Generator: func() string {
-			return reqId
+			return reqID
 		},
 		ContextKey: ctxKey,
 	}))
@@ -68,11 +68,11 @@ func Test_RequestID_Locals(t *testing.T) {
 	var ctxVal string
 
 	app.Use(func(c *fiber.Ctx) error {
-		ctxVal = c.Locals(ctxKey).(string)
+		ctxVal = c.Locals(ctxKey).(string) //nolint:forcetypeassert,errcheck // We always store a string in here
 		return c.Next()
 	})
 
-	_, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
-	utils.AssertEqual(t, reqId, ctxVal)
+	utils.AssertEqual(t, reqID, ctxVal)
 }

middleware/session/README.md

@@ -32,7 +32,7 @@ func (s *Session) Save() error
 func (s *Session) Fresh() bool
 func (s *Session) ID() string
 func (s *Session) Keys() []string
-func (s *Session) SetExpiry(time.Duration) 
+func (s *Session) SetExpiry(time.Duration)
 ```
 
 **⚠ _Storing `interface{}` values are limited to built-ins Go types_**
@@ -148,7 +148,7 @@ type Config struct {
 	// Optional. Default value utils.UUID
 	KeyGenerator func() string
 
-	// Deprecated, please use KeyLookup
+	// Deprecated: Please use KeyLookup
 	CookieName string
 
 	// Source defines where to obtain the session id

middleware/session/config.go

@@ -2,6 +2,7 @@ package session
 
 import (
 	"fmt"
+	"log"
 	"strings"
 	"time"
 
@@ -49,7 +50,7 @@ type Config struct {
 	// Optional. Default value utils.UUIDv4
 	KeyGenerator func() string
 
-	// Deprecated, please use KeyLookup
+	// Deprecated: Please use KeyLookup
 	CookieName string
 
 	// Source defines where to obtain the session id
@@ -68,8 +69,10 @@ const (
 )
 
 // ConfigDefault is the default config
+//
+//nolint:gochecknoglobals // Using a global var is fine here
 var ConfigDefault = Config{
-	Expiration:   24 * time.Hour,
+	Expiration:   24 * time.Hour, //nolint:gomnd // No magic number, just the default config
 	KeyLookup:    "cookie:session_id",
 	KeyGenerator: utils.UUIDv4,
 	source:       "cookie",
@@ -91,7 +94,7 @@ func configDefault(config ...Config) Config {
 		cfg.Expiration = ConfigDefault.Expiration
 	}
 	if cfg.CookieName != "" {
-		fmt.Println("[session] CookieName is deprecated, please use KeyLookup")
+		log.Printf("[session] CookieName is deprecated, please use KeyLookup\n")
 		cfg.KeyLookup = fmt.Sprintf("cookie:%s", cfg.CookieName)
 	}
 	if cfg.KeyLookup == "" {
@@ -102,7 +105,8 @@ func configDefault(config ...Config) Config {
 	}
 
 	selectors := strings.Split(cfg.KeyLookup, ":")
-	if len(selectors) != 2 {
+	const numSelectors = 2
+	if len(selectors) != numSelectors {
 		panic("[session] KeyLookup must in the form of <source>:<name>")
 	}
 	switch Source(selectors[0]) {

middleware/session/data.go

@@ -13,6 +13,7 @@ type data struct {
 	Data map[string]interface{}
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var dataPool = sync.Pool{
 	New: func() interface{} {
 		d := new(data)
@@ -22,7 +23,7 @@ var dataPool = sync.Pool{
 }
 
 func acquireData() *data {
-	return dataPool.Get().(*data)
+	return dataPool.Get().(*data) //nolint:forcetypeassert // We store nothing else in the pool
 }
 
 func (d *data) Reset() {

middleware/session/session.go

@@ -3,11 +3,13 @@ package session
 import (
 	"bytes"
 	"encoding/gob"
+	"fmt"
 	"sync"
 	"time"
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -21,6 +23,7 @@ type Session struct {
 	exp        time.Duration // expiration of this session
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var sessionPool = sync.Pool{
 	New: func() interface{} {
 		return new(Session)
@@ -28,7 +31,7 @@ var sessionPool = sync.Pool{
 }
 
 func acquireSession() *Session {
-	s := sessionPool.Get().(*Session)
+	s := sessionPool.Get().(*Session) //nolint:forcetypeassert,errcheck // We store nothing else in the pool
 	if s.data == nil {
 		s.data = acquireData()
 	}
@@ -153,7 +156,7 @@ func (s *Session) Save() error {
 	encCache := gob.NewEncoder(s.byteBuffer)
 	err := encCache.Encode(&s.data.Data)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to encode data: %w", err)
 	}
 
 	// copy the data in buffer

middleware/session/session_test.go

@@ -7,6 +7,7 @@ import (
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -94,6 +95,8 @@ func Test_Session(t *testing.T) {
 }
 
 // go test -run Test_Session_Types
+//
+//nolint:forcetypeassert // TODO: Do not force-type assert
 func Test_Session_Types(t *testing.T) {
 	t.Parallel()
 
@@ -127,25 +130,27 @@ func Test_Session_Types(t *testing.T) {
 		Name: "John",
 	}
 	// set value
-	var vbool = true
-	var vstring = "str"
-	var vint = 13
-	var vint8 int8 = 13
-	var vint16 int16 = 13
-	var vint32 int32 = 13
-	var vint64 int64 = 13
-	var vuint uint = 13
-	var vuint8 uint8 = 13
-	var vuint16 uint16 = 13
-	var vuint32 uint32 = 13
-	var vuint64 uint64 = 13
-	var vuintptr uintptr = 13
-	var vbyte byte = 'k'
-	var vrune rune = 'k'
-	var vfloat32 float32 = 13
-	var vfloat64 float64 = 13
-	var vcomplex64 complex64 = 13
-	var vcomplex128 complex128 = 13
+	var (
+		vbool                  = true
+		vstring                = "str"
+		vint                   = 13
+		vint8       int8       = 13
+		vint16      int16      = 13
+		vint32      int32      = 13
+		vint64      int64      = 13
+		vuint       uint       = 13
+		vuint8      uint8      = 13
+		vuint16     uint16     = 13
+		vuint32     uint32     = 13
+		vuint64     uint64     = 13
+		vuintptr    uintptr    = 13
+		vbyte       byte       = 'k'
+		vrune                  = 'k'
+		vfloat32    float32    = 13
+		vfloat64    float64    = 13
+		vcomplex64  complex64  = 13
+		vcomplex128 complex128 = 13
+	)
 	sess.Set("vuser", vuser)
 	sess.Set("vbool", vbool)
 	sess.Set("vstring", vstring)
@@ -212,7 +217,8 @@ func Test_Session_Store_Reset(t *testing.T) {
 	defer app.ReleaseCtx(ctx)
 
 	// get session
-	sess, _ := store.Get(ctx)
+	sess, err := store.Get(ctx)
+	utils.AssertEqual(t, nil, err)
 	// make sure its new
 	utils.AssertEqual(t, true, sess.Fresh())
 	// set value & save
@@ -224,7 +230,8 @@ func Test_Session_Store_Reset(t *testing.T) {
 	utils.AssertEqual(t, nil, store.Reset())
 
 	// make sure the session is recreated
-	sess, _ = store.Get(ctx)
+	sess, err = store.Get(ctx)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, true, sess.Fresh())
 	utils.AssertEqual(t, nil, sess.Get("hello"))
 }
@@ -242,12 +249,13 @@ func Test_Session_Save(t *testing.T) {
 		ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 		defer app.ReleaseCtx(ctx)
 		// get session
-		sess, _ := store.Get(ctx)
+		sess, err := store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 		// set value
 		sess.Set("name", "john")
 
 		// save session
-		err := sess.Save()
+		err = sess.Save()
 		utils.AssertEqual(t, nil, err)
 	})
 
@@ -262,12 +270,13 @@ func Test_Session_Save(t *testing.T) {
 		ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 		defer app.ReleaseCtx(ctx)
 		// get session
-		sess, _ := store.Get(ctx)
+		sess, err := store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 		// set value
 		sess.Set("name", "john")
 
 		// save session
-		err := sess.Save()
+		err = sess.Save()
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, store.getSessionID(ctx), string(ctx.Response().Header.Peek(store.sessionName)))
 		utils.AssertEqual(t, store.getSessionID(ctx), string(ctx.Request().Header.Peek(store.sessionName)))
@@ -287,7 +296,8 @@ func Test_Session_Save_Expiration(t *testing.T) {
 		ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 		defer app.ReleaseCtx(ctx)
 		// get session
-		sess, _ := store.Get(ctx)
+		sess, err := store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 		// set value
 		sess.Set("name", "john")
 
@@ -295,18 +305,20 @@ func Test_Session_Save_Expiration(t *testing.T) {
 		sess.SetExpiry(time.Second * 5)
 
 		// save session
-		err := sess.Save()
+		err = sess.Save()
 		utils.AssertEqual(t, nil, err)
 
 		// here you need to get the old session yet
-		sess, _ = store.Get(ctx)
+		sess, err = store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, "john", sess.Get("name"))
 
 		// just to make sure the session has been expired
 		time.Sleep(time.Second * 5)
 
 		// here you should get a new session
-		sess, _ = store.Get(ctx)
+		sess, err = store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, nil, sess.Get("name"))
 	})
 }
@@ -325,7 +337,8 @@ func Test_Session_Reset(t *testing.T) {
 		ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 		defer app.ReleaseCtx(ctx)
 		// get session
-		sess, _ := store.Get(ctx)
+		sess, err := store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 
 		sess.Set("name", "fenny")
 		utils.AssertEqual(t, nil, sess.Destroy())
@@ -345,14 +358,16 @@ func Test_Session_Reset(t *testing.T) {
 		ctx := app.AcquireCtx(&fasthttp.RequestCtx{})
 		defer app.ReleaseCtx(ctx)
 		// get session
-		sess, _ := store.Get(ctx)
+		sess, err := store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 
 		// set value & save
 		sess.Set("name", "fenny")
 		utils.AssertEqual(t, nil, sess.Save())
-		sess, _ = store.Get(ctx)
+		sess, err = store.Get(ctx)
+		utils.AssertEqual(t, nil, err)
 
-		err := sess.Destroy()
+		err = sess.Destroy()
 		utils.AssertEqual(t, nil, err)
 		utils.AssertEqual(t, "", string(ctx.Response().Header.Peek(store.sessionName)))
 		utils.AssertEqual(t, "", string(ctx.Request().Header.Peek(store.sessionName)))
@@ -383,7 +398,8 @@ func Test_Session_Cookie(t *testing.T) {
 	defer app.ReleaseCtx(ctx)
 
 	// get session
-	sess, _ := store.Get(ctx)
+	sess, err := store.Get(ctx)
+	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, nil, sess.Save())
 
 	// cookie should be set on Save ( even if empty data )
@@ -401,12 +417,14 @@ func Test_Session_Cookie_In_Response(t *testing.T) {
 	defer app.ReleaseCtx(ctx)
 
 	// get session
-	sess, _ := store.Get(ctx)
+	sess, err := store.Get(ctx)
+	utils.AssertEqual(t, nil, err)
 	sess.Set("id", "1")
 	utils.AssertEqual(t, true, sess.Fresh())
 	utils.AssertEqual(t, nil, sess.Save())
 
-	sess, _ = store.Get(ctx)
+	sess, err = store.Get(ctx)
+	utils.AssertEqual(t, nil, err)
 	sess.Set("name", "john")
 	utils.AssertEqual(t, true, sess.Fresh())
 
@@ -497,7 +515,7 @@ func Benchmark_Session(b *testing.B) {
 		b.ReportAllocs()
 		b.ResetTimer()
 		for n := 0; n < b.N; n++ {
-			sess, _ := store.Get(c)
+			sess, _ := store.Get(c) //nolint:errcheck // We're inside a benchmark
 			sess.Set("john", "doe")
 			err = sess.Save()
 		}
@@ -512,7 +530,7 @@ func Benchmark_Session(b *testing.B) {
 		b.ReportAllocs()
 		b.ResetTimer()
 		for n := 0; n < b.N; n++ {
-			sess, _ := store.Get(c)
+			sess, _ := store.Get(c) //nolint:errcheck // We're inside a benchmark
 			sess.Set("john", "doe")
 			err = sess.Save()
 		}

middleware/session/store.go

@@ -2,11 +2,13 @@ package session
 
 import (
 	"encoding/gob"
+	"fmt"
 	"sync"
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/internal/storage/memory"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 
@@ -14,6 +16,7 @@ type Store struct {
 	Config
 }
 
+//nolint:gochecknoglobals // TODO: Do not use a global var here
 var mux sync.Mutex
 
 func New(config ...Config) *Store {
@@ -31,7 +34,7 @@ func New(config ...Config) *Store {
 
 // RegisterType will allow you to encode/decode custom types
 // into any Storage provider
-func (s *Store) RegisterType(i interface{}) {
+func (*Store) RegisterType(i interface{}) {
 	gob.Register(i)
 }
 
@@ -70,11 +73,11 @@ func (s *Store) Get(c *fiber.Ctx) (*Session, error) {
 		if raw != nil && err == nil {
 			mux.Lock()
 			defer mux.Unlock()
-			_, _ = sess.byteBuffer.Write(raw)
+			_, _ = sess.byteBuffer.Write(raw) //nolint:errcheck // This will never fail
 			encCache := gob.NewDecoder(sess.byteBuffer)
 			err := encCache.Decode(&sess.data.Data)
 			if err != nil {
-				return nil, err
+				return nil, fmt.Errorf("failed to decode session data: %w", err)
 			}
 		} else if err != nil {
 			return nil, err

middleware/session/store_test.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/gofiber/fiber/v2"
 	"github.com/gofiber/fiber/v2/utils"
+
 	"github.com/valyala/fasthttp"
 )
 

middleware/skip/skip.go

@@ -1,6 +1,8 @@
 package skip
 
-import "github.com/gofiber/fiber/v2"
+import (
+	"github.com/gofiber/fiber/v2"
+)
 
 // New creates a middleware handler which skips the wrapped handler
 // if the exclude predicate returns true.

middleware/skip/skip_test.go

@@ -17,7 +17,7 @@ func Test_Skip(t *testing.T) {
 	app.Use(skip.New(errTeapotHandler, func(*fiber.Ctx) bool { return true }))
 	app.Get("/", helloWorldHandler)
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode)
 }
@@ -30,7 +30,7 @@ func Test_SkipFalse(t *testing.T) {
 	app.Use(skip.New(errTeapotHandler, func(*fiber.Ctx) bool { return false }))
 	app.Get("/", helloWorldHandler)
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusTeapot, resp.StatusCode)
 }
@@ -43,7 +43,7 @@ func Test_SkipNilFunc(t *testing.T) {
 	app.Use(skip.New(errTeapotHandler, nil))
 	app.Get("/", helloWorldHandler)
 
-	resp, err := app.Test(httptest.NewRequest("GET", "/", nil))
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
 	utils.AssertEqual(t, nil, err)
 	utils.AssertEqual(t, fiber.StatusTeapot, resp.StatusCode)
 }

middleware/timeout/timeout_test.go

@@ -18,7 +18,8 @@ func Test_Timeout(t *testing.T) {
 	// fiber instance
 	app := fiber.New()
 	h := New(func(c *fiber.Ctx) error {
-		sleepTime, _ := time.ParseDuration(c.Params("sleepTime") + "ms")
+		sleepTime, err := time.ParseDuration(c.Params("sleepTime") + "ms")
+		utils.AssertEqual(t, nil, err)
 		if err := sleepWithContext(c.UserContext(), sleepTime, context.DeadlineExceeded); err != nil {
 			return fmt.Errorf("%w: l2 wrap", fmt.Errorf("%w: l1 wrap ", err))
 		}
@@ -26,12 +27,12 @@ func Test_Timeout(t *testing.T) {
 	}, 100*time.Millisecond)
 	app.Get("/test/:sleepTime", h)
 	testTimeout := func(timeoutStr string) {
-		resp, err := app.Test(httptest.NewRequest("GET", "/test/"+timeoutStr, nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/test/"+timeoutStr, nil))
 		utils.AssertEqual(t, nil, err, "app.Test(req)")
 		utils.AssertEqual(t, fiber.StatusRequestTimeout, resp.StatusCode, "Status code")
 	}
 	testSucces := func(timeoutStr string) {
-		resp, err := app.Test(httptest.NewRequest("GET", "/test/"+timeoutStr, nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/test/"+timeoutStr, nil))
 		utils.AssertEqual(t, nil, err, "app.Test(req)")
 		utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 	}
@@ -49,7 +50,8 @@ func Test_TimeoutWithCustomError(t *testing.T) {
 	// fiber instance
 	app := fiber.New()
 	h := New(func(c *fiber.Ctx) error {
-		sleepTime, _ := time.ParseDuration(c.Params("sleepTime") + "ms")
+		sleepTime, err := time.ParseDuration(c.Params("sleepTime") + "ms")
+		utils.AssertEqual(t, nil, err)
 		if err := sleepWithContext(c.UserContext(), sleepTime, ErrFooTimeOut); err != nil {
 			return fmt.Errorf("%w: execution error", err)
 		}
@@ -57,12 +59,12 @@ func Test_TimeoutWithCustomError(t *testing.T) {
 	}, 100*time.Millisecond, ErrFooTimeOut)
 	app.Get("/test/:sleepTime", h)
 	testTimeout := func(timeoutStr string) {
-		resp, err := app.Test(httptest.NewRequest("GET", "/test/"+timeoutStr, nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/test/"+timeoutStr, nil))
 		utils.AssertEqual(t, nil, err, "app.Test(req)")
 		utils.AssertEqual(t, fiber.StatusRequestTimeout, resp.StatusCode, "Status code")
 	}
 	testSucces := func(timeoutStr string) {
-		resp, err := app.Test(httptest.NewRequest("GET", "/test/"+timeoutStr, nil))
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/test/"+timeoutStr, nil))
 		utils.AssertEqual(t, nil, err, "app.Test(req)")
 		utils.AssertEqual(t, fiber.StatusOK, resp.StatusCode, "Status code")
 	}