🔥 feat: Add Skip function to logger middleware (#3333)

* 🔥 Feature(logger): Add Filter option to logger middleware

* 📚 Doc(logger): Clarify Filter middleware description

* 🚨 Test(logger): Enhance logger filter test with parallel subtests

* 🔒 Test(logger): Add mutex to prevent race conditions in logger test

* 🔥 Feature(logger): Add Filter option to logger middleware

* 📚 Doc(logger): Clarify Filter middleware description

* 🚨 Test(logger): Enhance logger filter test with parallel subtests

* 🔒 Test(logger): Add mutex to prevent race conditions in logger test

* 🚨 Test(logger): Refactor logger test to improve test isolation

* Fix issue with unit-tests

* Update middleware/logger/logger_test.go

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

* Apply logger filter as soon as possible

* 📚 Doc: Add logger filter configuration example to whats_new.md

* 📚 Doc: Update logger filter documentation in whats_new.md

* 📚 Doc: Update logger filter documentation and examples

* 🩹 Fix: improve what_new.md

* Update logic for Filter() in Logger middleware. Add more unit-tests

* Rename fields to match expressjs/morgan

* Update middleware/logger/default_logger.go

---------

Co-authored-by: Juan Calderon-Perez <jgcalderonperez@protonmail.com>
Co-authored-by: Juan Calderon-Perez <835733+gaby@users.noreply.github.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Co-authored-by: RW <rene@gofiber.io>

docs/middleware/logger.md

@@ -55,13 +55,13 @@ app.Use(logger.New(logger.Config{
 }))
 
 // Custom File Writer
-file, err := os.OpenFile("./123.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+accessLog, err := os.OpenFile("./access.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
 if err != nil {
-    log.Fatalf("error opening file: %v", err)
+    log.Fatalf("error opening access.log file: %v", err)
 }
-defer file.Close()
+defer accessLog.Close()
 app.Use(logger.New(logger.Config{
-    Output: file,
+    Stream: accessLog,
 }))
 
 // Add Custom Tags
@@ -115,7 +115,7 @@ func main() {
 
     // Use the logger middleware with zerolog logger
     app.Use(logger.New(logger.Config{
-        Output: logger.LoggerToWriter(zap, log.LevelDebug),
+        Stream: logger.LoggerToWriter(zap, log.LevelDebug),
     }))
 
     // Define a route
@@ -129,7 +129,7 @@ func main() {
 ```
 
 :::tip
-Writing to os.File is goroutine-safe, but if you are using a custom Output that is not goroutine-safe, make sure to implement locking to properly serialize writes.
+Writing to os.File is goroutine-safe, but if you are using a custom Stream that is not goroutine-safe, make sure to implement locking to properly serialize writes.
 :::
 
 ## Config
@@ -138,31 +138,30 @@ Writing to os.File is goroutine-safe, but if you are using a custom Output that
 
 | Property         | Type                       | Description                                                                                                                      | Default                                                               |
 |:-----------------|:---------------------------|:---------------------------------------------------------------------------------------------------------------------------------|:----------------------------------------------------------------------|
-| Next             | `func(fiber.Ctx) bool`    | Next defines a function to skip this middleware when returned true.                                                              | `nil`                                                                 |
+| Next             | `func(fiber.Ctx) bool`     | Next defines a function to skip this middleware when returned true.                                                               | `nil`                                                                 |
-| Done             | `func(fiber.Ctx, []byte)` | Done is a function that is called after the log string for a request is written to Output, and pass the log string as parameter. | `nil`                                                                 |
+| Skip             | `func(fiber.Ctx) bool`     | Skip is a function to determine if logging is skipped or written to Stream.                                                       | `nil`                                                                 |
+| Done             | `func(fiber.Ctx, []byte)`  | Done is a function that is called after the log string for a request is written to Stream, and pass the log string as parameter.  | `nil`                                                                 |
 | CustomTags       | `map[string]LogFunc`       | tagFunctions defines the custom tag action.                                                                                      | `map[string]LogFunc`                                                  |
 | Format           | `string`                   | Format defines the logging tags.                                                                                                 | `[${time}] ${ip} ${status} - ${latency} ${method} ${path} ${error}\n` |
 | TimeFormat       | `string`                   | TimeFormat defines the time format for log timestamps.                                                                           | `15:04:05`                                                            |
 | TimeZone         | `string`                   | TimeZone can be specified, such as "UTC" and "America/New_York" and "Asia/Chongqing", etc                                        | `"Local"`                                                             |
 | TimeInterval     | `time.Duration`            | TimeInterval is the delay before the timestamp is updated.                                                                       | `500 * time.Millisecond`                                              |
-| Output           | `io.Writer`                | Output is a writer where logs are written.                                                                                       | `os.Stdout`                                                           |
+| Stream           | `io.Writer`                | Stream is a writer where logs are written.                                                                                       | `os.Stdout`                                                           |
 | LoggerFunc | `func(c fiber.Ctx, data *Data, cfg Config) error` | Custom logger function for integration with logging libraries (Zerolog, Zap, Logrus, etc). Defaults to Fiber's default logger if not defined. | `see default_logger.go defaultLoggerInstance` |
 | DisableColors    | `bool`                     | DisableColors defines if the logs output should be colorized.                                                                    | `false`                                                               |
-| enableColors     | `bool`                     | Internal field for enabling colors in the log output. (This is not a user-configurable field)                                    | -                                                                     |
-| enableLatency    | `bool`                     | Internal field for enabling latency measurement in logs. (This is not a user-configurable field)                                 | -                                                                     |
-| timeZoneLocation | `*time.Location`           | Internal field for the time zone location. (This is not a user-configurable field)                                               | -                                                                     |
 
 ## Default Config
 
 ```go
 var ConfigDefault = Config{
     Next:          nil,
+    Skip           nil,
     Done:          nil,
     Format:        "[${time}] ${ip} ${status} - ${latency} ${method} ${path} ${error}\n",
     TimeFormat:    "15:04:05",
     TimeZone:      "Local",
     TimeInterval:  500 * time.Millisecond,
-    Output:        os.Stdout,
+    Stream:        os.Stdout,
     DisableColors: false,
     LoggerFunc:    defaultLoggerInstance,
 }

docs/whats_new.md

@@ -912,6 +912,31 @@ func main() {
 
 </details>
 
+The `Skip` is a function to determine if logging is skipped or written to `Stream`.
+
+<details>
+<summary>Example Usage</summary>
+
+```go
+app.Use(logger.New(logger.Config{
+    Skip: func(c fiber.Ctx) bool {
+        // Skip logging HTTP 200 requests
+        return c.Response().StatusCode() == fiber.StatusOK
+    },
+}))
+```
+
+```go
+app.Use(logger.New(logger.Config{
+    Skip: func(c fiber.Ctx) bool {
+        // Only log errors, similar to an error.log
+        return c.Response().StatusCode() < 400
+    },
+}))
+```
+
+</details>
+
 ### Filesystem
 
 We've decided to remove filesystem middleware to clear up the confusion between static and filesystem middleware.

middleware/logger/config.go

@@ -10,16 +10,21 @@ import (
 
 // Config defines the config for middleware.
 type Config struct {
-	// Output is a writer where logs are written
+	// Stream is a writer where logs are written
 	//
 	// Default: os.Stdout
-	Output io.Writer
+	Stream io.Writer
 
 	// Next defines a function to skip this middleware when returned true.
 	//
 	// Optional. Default: nil
 	Next func(c fiber.Ctx) bool
 
+	// Skip is a function to determine if logging is skipped or written to Stream.
+	//
+	// Optional. Default: nil
+	Skip func(c fiber.Ctx) bool
+
 	// Done is a function that is called after the log string for a request is written to Output,
 	// and pass the log string as parameter.
 	//
@@ -98,12 +103,13 @@ type LogFunc func(output Buffer, c fiber.Ctx, data *Data, extraParam string) (in
 // ConfigDefault is the default config
 var ConfigDefault = Config{
 	Next:              nil,
+	Skip:              nil,
 	Done:              nil,
 	Format:            defaultFormat,
 	TimeFormat:        "15:04:05",
 	TimeZone:          "Local",
 	TimeInterval:      500 * time.Millisecond,
-	Output:            os.Stdout,
+	Stream:            os.Stdout,
 	BeforeHandlerFunc: beforeHandlerFunc,
 	LoggerFunc:        defaultLoggerInstance,
 	enableColors:      true,
@@ -126,6 +132,9 @@ func configDefault(config ...Config) Config {
 	if cfg.Next == nil {
 		cfg.Next = ConfigDefault.Next
 	}
+	if cfg.Skip == nil {
+		cfg.Skip = ConfigDefault.Skip
+	}
 	if cfg.Done == nil {
 		cfg.Done = ConfigDefault.Done
 	}
@@ -141,8 +150,8 @@ func configDefault(config ...Config) Config {
 	if int(cfg.TimeInterval) <= 0 {
 		cfg.TimeInterval = ConfigDefault.TimeInterval
 	}
-	if cfg.Output == nil {
+	if cfg.Stream == nil {
-		cfg.Output = ConfigDefault.Output
+		cfg.Stream = ConfigDefault.Stream
 	}
 
 	if cfg.BeforeHandlerFunc == nil {
@@ -154,7 +163,7 @@ func configDefault(config ...Config) Config {
 	}
 
 	// Enable colors if no custom format or output is given
-	if !cfg.DisableColors && cfg.Output == ConfigDefault.Output {
+	if !cfg.DisableColors && cfg.Stream == ConfigDefault.Stream {
 		cfg.enableColors = true
 	}
 

middleware/logger/default_logger.go

@@ -15,6 +15,12 @@ import (
 
 // default logger for fiber
 func defaultLoggerInstance(c fiber.Ctx, data *Data, cfg Config) error {
+	// Check if Skip is defined and call it.
+	// Now, if Skip(c) == true, we SKIP logging:
+	if cfg.Skip != nil && cfg.Skip(c) {
+		return nil // Skip logging if Skip returns true
+	}
+
 	// Alias colors
 	colors := c.App().Config().ColorScheme
 
@@ -91,7 +97,7 @@ func defaultLoggerInstance(c fiber.Ctx, data *Data, cfg Config) error {
 		}
 
 		// Write buffer to output
-		writeLog(cfg.Output, buf.Bytes())
+		writeLog(cfg.Stream, buf.Bytes())
 
 		if cfg.Done != nil {
 			cfg.Done(c, buf.Bytes())
@@ -125,7 +131,7 @@ func defaultLoggerInstance(c fiber.Ctx, data *Data, cfg Config) error {
 		buf.WriteString(err.Error())
 	}
 
-	writeLog(cfg.Output, buf.Bytes())
+	writeLog(cfg.Stream, buf.Bytes())
 
 	if cfg.Done != nil {
 		cfg.Done(c, buf.Bytes())
@@ -141,9 +147,9 @@ func defaultLoggerInstance(c fiber.Ctx, data *Data, cfg Config) error {
 func beforeHandlerFunc(cfg Config) {
 	// If colors are enabled, check terminal compatibility
 	if cfg.enableColors {
-		cfg.Output = colorable.NewColorableStdout()
+		cfg.Stream = colorable.NewColorableStdout()
 		if os.Getenv("TERM") == "dumb" || os.Getenv("NO_COLOR") == "1" || (!isatty.IsTerminal(os.Stdout.Fd()) && !isatty.IsCygwinTerminal(os.Stdout.Fd())) {
-			cfg.Output = colorable.NewNonColorable(os.Stdout)
+			cfg.Stream = colorable.NewNonColorable(os.Stdout)
 		}
 	}
 }

middleware/logger/logger_test.go

@@ -71,7 +71,7 @@ func Test_Logger(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${error}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Get("/", func(_ fiber.Ctx) error {
@@ -94,7 +94,7 @@ func Test_Logger_locals(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${locals:demo}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Get("/", func(c fiber.Ctx) error {
@@ -171,6 +171,147 @@ func Test_Logger_Done(t *testing.T) {
 	require.Positive(t, buf.Len(), 0)
 }
 
+// Test_Logger_Filter tests the Filter functionality of the logger middleware.
+// It verifies that logs are written or skipped based on the filter condition.
+func Test_Logger_Filter(t *testing.T) {
+	t.Parallel()
+
+	t.Run("Test Not Found", func(t *testing.T) {
+		t.Parallel()
+		app := fiber.New()
+
+		logOutput := bytes.Buffer{}
+
+		// Return true to skip logging for all requests != 404
+		app.Use(New(Config{
+			Skip: func(c fiber.Ctx) bool {
+				return c.Response().StatusCode() != fiber.StatusNotFound
+			},
+			Stream: &logOutput,
+		}))
+
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/nonexistent", nil))
+		require.NoError(t, err)
+		require.Equal(t, fiber.StatusNotFound, resp.StatusCode)
+
+		// Expect logs for the 404 request
+		require.Contains(t, logOutput.String(), "404")
+	})
+
+	t.Run("Test OK", func(t *testing.T) {
+		t.Parallel()
+		app := fiber.New()
+
+		logOutput := bytes.Buffer{}
+
+		// Return true to skip logging for all requests == 200
+		app.Use(New(Config{
+			Skip: func(c fiber.Ctx) bool {
+				return c.Response().StatusCode() == fiber.StatusOK
+			},
+			Stream: &logOutput,
+		}))
+
+		app.Get("/", func(c fiber.Ctx) error {
+			return c.SendStatus(fiber.StatusOK)
+		})
+
+		resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+		require.NoError(t, err)
+		require.Equal(t, fiber.StatusOK, resp.StatusCode)
+
+		// We skip logging for status == 200, so "200" should not appear
+		require.NotContains(t, logOutput.String(), "200")
+	})
+
+	t.Run("Always Skip", func(t *testing.T) {
+		t.Parallel()
+		app := fiber.New()
+
+		logOutput := bytes.Buffer{}
+
+		// Filter always returns true => skip all logs
+		app.Use(New(Config{
+			Skip: func(_ fiber.Ctx) bool {
+				return true // always skip
+			},
+			Stream: &logOutput,
+		}))
+
+		app.Get("/something", func(c fiber.Ctx) error {
+			return c.Status(fiber.StatusTeapot).SendString("I'm a teapot")
+		})
+
+		_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/something", nil))
+		require.NoError(t, err)
+
+		// Expect NO logs
+		require.Empty(t, logOutput.String())
+	})
+
+	t.Run("Never Skip", func(t *testing.T) {
+		t.Parallel()
+		app := fiber.New()
+
+		logOutput := bytes.Buffer{}
+
+		// Filter always returns false => never skip logs
+		app.Use(New(Config{
+			Skip: func(_ fiber.Ctx) bool {
+				return false // never skip
+			},
+			Stream: &logOutput,
+		}))
+
+		app.Get("/always", func(c fiber.Ctx) error {
+			return c.Status(fiber.StatusTeapot).SendString("Teapot again")
+		})
+
+		_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/always", nil))
+		require.NoError(t, err)
+
+		// Expect some logging - check any substring
+		require.Contains(t, logOutput.String(), strconv.Itoa(fiber.StatusTeapot))
+	})
+
+	t.Run("Skip /healthz", func(t *testing.T) {
+		t.Parallel()
+		app := fiber.New()
+
+		logOutput := bytes.Buffer{}
+
+		// Filter returns true (skip logs) if the request path is /healthz
+		app.Use(New(Config{
+			Skip: func(c fiber.Ctx) bool {
+				return c.Path() == "/healthz"
+			},
+			Stream: &logOutput,
+		}))
+
+		// Normal route
+		app.Get("/", func(c fiber.Ctx) error {
+			return c.SendString("Hello World!")
+		})
+		// Health route
+		app.Get("/healthz", func(c fiber.Ctx) error {
+			return c.SendString("OK")
+		})
+
+		// Request to "/" -> should be logged
+		_, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+		require.NoError(t, err)
+		require.Contains(t, logOutput.String(), "200")
+
+		// Reset output buffer
+		logOutput.Reset()
+
+		// Request to "/healthz" -> should be skipped
+		_, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/healthz", nil))
+		require.NoError(t, err)
+		require.Empty(t, logOutput.String())
+	})
+}
+
 // go test -run Test_Logger_ErrorTimeZone
 func Test_Logger_ErrorTimeZone(t *testing.T) {
 	t.Parallel()
@@ -234,7 +375,7 @@ func Test_Logger_LoggerToWriter(t *testing.T) {
 
 			app.Use("/"+level, New(Config{
 				Format: "${error}",
-				Output: LoggerToWriter(logger, tc.
+				Stream: LoggerToWriter(logger, tc.
 					level),
 			}))
 
@@ -276,7 +417,7 @@ func Test_Logger_ErrorOutput_WithoutColor(t *testing.T) {
 	app := fiber.New()
 
 	app.Use(New(Config{
-		Output:        o,
+		Stream:        o,
 		DisableColors: true,
 	}))
 
@@ -293,7 +434,7 @@ func Test_Logger_ErrorOutput(t *testing.T) {
 	app := fiber.New()
 
 	app.Use(New(Config{
-		Output: o,
+		Stream: o,
 	}))
 
 	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
@@ -312,7 +453,7 @@ func Test_Logger_All(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${pid}${reqHeaders}${referer}${scheme}${protocol}${ip}${ips}${host}${url}${ua}${body}${route}${black}${red}${green}${yellow}${blue}${magenta}${cyan}${white}${reset}${error}${reqHeader:test}${query:test}${form:test}${cookie:test}${non}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	// Alias colors
@@ -358,7 +499,7 @@ func Test_Logger_WithLatency(t *testing.T) {
 	app := fiber.New()
 
 	logger := New(Config{
-		Output: buff,
+		Stream: buff,
 		Format: "${latency}",
 	})
 	app.Use(logger)
@@ -403,7 +544,7 @@ func Test_Logger_WithLatency_DefaultFormat(t *testing.T) {
 	app := fiber.New()
 
 	logger := New(Config{
-		Output: buff,
+		Stream: buff,
 	})
 	app.Use(logger)
 
@@ -453,7 +594,7 @@ func Test_Query_Params(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${queryParams}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/?foo=bar&baz=moz", nil))
@@ -474,7 +615,7 @@ func Test_Response_Body(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${resBody}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Get("/", func(c fiber.Ctx) error {
@@ -508,7 +649,7 @@ func Test_Request_Body(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${bytesReceived} ${bytesSent} ${status}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Post("/", func(c fiber.Ctx) error {
@@ -536,7 +677,7 @@ func Test_Logger_AppendUint(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${bytesReceived} ${bytesSent} ${status}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Get("/", func(c fiber.Ctx) error {
@@ -611,7 +752,7 @@ func Test_Response_Header(t *testing.T) {
 	}))
 	app.Use(New(Config{
 		Format: "${respHeader:X-Request-ID}",
-		Output: buf,
+		Stream: buf,
 	}))
 	app.Get("/", func(c fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
@@ -634,7 +775,7 @@ func Test_Req_Header(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${reqHeader:test}",
-		Output: buf,
+		Stream: buf,
 	}))
 	app.Get("/", func(c fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
@@ -658,7 +799,7 @@ func Test_ReqHeader_Header(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${reqHeader:test}",
-		Output: buf,
+		Stream: buf,
 	}))
 	app.Get("/", func(c fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
@@ -689,7 +830,7 @@ func Test_CustomTags(t *testing.T) {
 				return output.WriteString(customTag)
 			},
 		},
-		Output: buf,
+		Stream: buf,
 	}))
 	app.Get("/", func(c fiber.Ctx) error {
 		return c.SendString("Hello fiber!")
@@ -713,7 +854,7 @@ func Test_Logger_ByteSent_Streaming(t *testing.T) {
 
 	app.Use(New(Config{
 		Format: "${bytesReceived} ${bytesSent} ${status}",
-		Output: buf,
+		Stream: buf,
 	}))
 
 	app.Get("/", func(c fiber.Ctx) error {
@@ -759,7 +900,7 @@ func Test_Logger_EnableColors(t *testing.T) {
 	app := fiber.New()
 
 	app.Use(New(Config{
-		Output: o,
+		Stream: o,
 	}))
 
 	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
@@ -782,7 +923,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("test", "test")
@@ -794,7 +935,7 @@ func Benchmark_Logger(b *testing.B) {
 	b.Run("DefaultFormat", func(bb *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -805,7 +946,7 @@ func Benchmark_Logger(b *testing.B) {
 	b.Run("DefaultFormatDisableColors", func(bb *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
-			Output:        io.Discard,
+			Stream:        io.Discard,
 			DisableColors: true,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
@@ -819,7 +960,7 @@ func Benchmark_Logger(b *testing.B) {
 		logger := fiberlog.DefaultLogger()
 		logger.SetOutput(io.Discard)
 		app.Use(New(Config{
-			Output: LoggerToWriter(logger, fiberlog.LevelDebug),
+			Stream: LoggerToWriter(logger, fiberlog.LevelDebug),
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -831,7 +972,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status} ${reqHeader:test}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("test", "test")
@@ -844,7 +985,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${locals:demo}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Locals("demo", "johndoe")
@@ -857,7 +998,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${locals:demo}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/int", func(c fiber.Ctx) error {
 			c.Locals("demo", 55)
@@ -874,7 +1015,7 @@ func Benchmark_Logger(b *testing.B) {
 					io.Discard.Write(logString) //nolint:errcheck // ignore error
 				}
 			},
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/logging", func(ctx fiber.Ctx) error {
 			return ctx.SendStatus(fiber.StatusOK)
@@ -886,7 +1027,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${pid}${reqHeaders}${referer}${scheme}${protocol}${ip}${ips}${host}${url}${ua}${body}${route}${black}${red}${green}${yellow}${blue}${magenta}${cyan}${white}${reset}${error}${reqHeader:test}${query:test}${form:test}${cookie:test}${non}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -898,7 +1039,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("Connection", "keep-alive")
@@ -927,7 +1068,7 @@ func Benchmark_Logger(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${resBody}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Sample response body")
@@ -950,7 +1091,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("test", "test")
@@ -962,7 +1103,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 	b.Run("DefaultFormat", func(bb *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -975,7 +1116,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		logger := fiberlog.DefaultLogger()
 		logger.SetOutput(io.Discard)
 		app.Use(New(Config{
-			Output: LoggerToWriter(logger, fiberlog.LevelDebug),
+			Stream: LoggerToWriter(logger, fiberlog.LevelDebug),
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -986,7 +1127,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 	b.Run("DefaultFormatDisableColors", func(bb *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
-			Output:        io.Discard,
+			Stream:        io.Discard,
 			DisableColors: true,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
@@ -999,7 +1140,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status} ${reqHeader:test}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("test", "test")
@@ -1012,7 +1153,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${locals:demo}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Locals("demo", "johndoe")
@@ -1025,7 +1166,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${locals:demo}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/int", func(c fiber.Ctx) error {
 			c.Locals("demo", 55)
@@ -1042,7 +1183,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 					io.Discard.Write(logString) //nolint:errcheck // ignore error
 				}
 			},
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/logging", func(ctx fiber.Ctx) error {
 			return ctx.SendStatus(fiber.StatusOK)
@@ -1054,7 +1195,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${pid}${reqHeaders}${referer}${scheme}${protocol}${ip}${ips}${host}${url}${ua}${body}${route}${black}${red}${green}${yellow}${blue}${magenta}${cyan}${white}${reset}${error}${reqHeader:test}${query:test}${form:test}${cookie:test}${non}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Hello, World!")
@@ -1066,7 +1207,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${bytesReceived} ${bytesSent} ${status}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			c.Set("Connection", "keep-alive")
@@ -1095,7 +1236,7 @@ func Benchmark_Logger_Parallel(b *testing.B) {
 		app := fiber.New()
 		app.Use(New(Config{
 			Format: "${resBody}",
-			Output: io.Discard,
+			Stream: io.Discard,
 		}))
 		app.Get("/", func(c fiber.Ctx) error {
 			return c.SendString("Sample response body")