From bfa0cab89288e3a33be21b5386faff2019eafb3c Mon Sep 17 00:00:00 2001
From: Wayne Chen <c360785655@gmail.com>
Date: Sat, 29 Feb 2020 21:00:54 +0800
Subject: [PATCH 1/2] support for range header

---
 context.go      | 54 ++++++++++++++++++++++++++++++++++++++++++++-----
 context_test.go | 19 ++++++++++++++++-
 2 files changed, 67 insertions(+), 6 deletions(-)

diff --git a/context.go b/context.go
index 292e7f9f..d01e3e98 100644
--- a/context.go
+++ b/context.go
@@ -13,6 +13,7 @@ import (
 	"mime/multipart"
 	"net/url"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -36,6 +37,15 @@ type Ctx struct {
 	Fasthttp *fasthttp.RequestCtx
 }
 
+// RangeInfo info of range header
+type RangeInfo struct {
+	Type   string
+	Ranges []struct {
+		Start int64
+		End   int64
+	}
+}
+
 // Ctx pool
 var poolCtx = sync.Pool{
 	New: func() interface{} {
@@ -548,11 +558,45 @@ func (ctx *Ctx) Query(key string) (value string) {
 }
 
 // Range : https://fiber.wiki/context#range
-func (ctx *Ctx) Range() {
-	// https://expressjs.com/en/api.html#req.range
-	// https://github.com/jshttp/range-parser/blob/master/index.js
-	// r := ctx.Fasthttp.Request.Header.Peek(HeaderRange)
-	// *magic*
+func (ctx *Ctx) Range(size int64) (rangeInfo RangeInfo, err error) {
+	rangeStr := string(ctx.Fasthttp.Request.Header.Peek("range"))
+	if rangeStr == "" || strings.Index(rangeStr, "=") < 0 {
+		return rangeInfo, fmt.Errorf("malformed range header string")
+	}
+	data := strings.Split(rangeStr, "=")
+	rangeInfo.Type = data[0]
+	arr := strings.Split(data[1], ",")
+	for i := 0; i < len(arr); i++ {
+		item := strings.Split(arr[i], "-")
+		if len(item) == 1 {
+			return rangeInfo, fmt.Errorf("malformed range header string")
+		}
+		start, startErr := strconv.ParseInt(item[0], 10, 64)
+		end, endErr := strconv.ParseInt(item[1], 10, 64)
+		if startErr != nil { // -nnn
+			start = size - end
+			end = size - 1
+		} else if endErr != nil { // nnn-
+			end = size - 1
+		}
+		if end > size-1 { // limit last-byte-pos to current length
+			end = size - 1
+		}
+		if start > end || start < 0 {
+			continue
+		}
+		rangeInfo.Ranges = append(rangeInfo.Ranges, struct {
+			Start int64
+			End   int64
+		}{
+			start,
+			end,
+		})
+	}
+	if len(rangeInfo.Ranges) < 1 {
+		return rangeInfo, fmt.Errorf("unsatisfiable range")
+	}
+	return rangeInfo, nil
 }
 
 // Redirect : https://fiber.wiki/context#redirect
diff --git a/context_test.go b/context_test.go
index 5b60b02b..7be23278 100644
--- a/context_test.go
+++ b/context_test.go
@@ -543,9 +543,26 @@ func Test_Query(t *testing.T) {
 func Test_Range(t *testing.T) {
 	app := New()
 	app.Get("/test", func(c *Ctx) {
-		c.Range()
+		result, err := c.Range(1000)
+		if err != nil {
+			t.Fatalf(`%s: %s`, t.Name(), err)
+			return
+		}
+		expect := "bytes"
+		if result.Type != expect {
+			t.Fatalf(`%s: Expecting %s, got %s`, t.Name(), expect, result.Type)
+		}
+		expectNum := int64(500)
+		if result.Ranges[0].Start != expectNum {
+			t.Fatalf(`%s: Expecting %v, got %v`, t.Name(), expectNum, result.Ranges[0].Start)
+		}
+		expectNum = int64(700)
+		if result.Ranges[0].End != expectNum {
+			t.Fatalf(`%s: Expecting %v, got %v`, t.Name(), expectNum, result.Ranges[0].End)
+		}
 	})
 	req, _ := http.NewRequest("GET", "/test", nil)
+	req.Header.Set("range", "bytes=500-700")
 	_, err := app.Test(req)
 	if err != nil {
 		t.Fatalf(`%s: %s`, t.Name(), err)

From 34c5e46fd0a6c6c11d1b08f05b8f363b6a527577 Mon Sep 17 00:00:00 2001
From: Wayne Chen <c360785655@gmail.com>
Date: Sat, 29 Feb 2020 21:12:17 +0800
Subject: [PATCH 2/2] improve code

---
 context.go | 2 +-
 go.mod     | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/context.go b/context.go
index d01e3e98..ab05336e 100644
--- a/context.go
+++ b/context.go
@@ -560,7 +560,7 @@ func (ctx *Ctx) Query(key string) (value string) {
 // Range : https://fiber.wiki/context#range
 func (ctx *Ctx) Range(size int64) (rangeInfo RangeInfo, err error) {
 	rangeStr := string(ctx.Fasthttp.Request.Header.Peek("range"))
-	if rangeStr == "" || strings.Index(rangeStr, "=") < 0 {
+	if rangeStr == "" || !strings.Contains(rangeStr, "=") {
 		return rangeInfo, fmt.Errorf("malformed range header string")
 	}
 	data := strings.Split(rangeStr, "=")
diff --git a/go.mod b/go.mod
index a8b89739..61666dda 100644
--- a/go.mod
+++ b/go.mod
@@ -3,9 +3,9 @@ module github.com/gofiber/fiber
 go 1.11
 
 require (
-	github.com/gorilla/schema v1.1.0
+	github.com/fasthttp/websocket v1.4.2
 	github.com/gofiber/template v1.0.0
+	github.com/gorilla/schema v1.1.0
 	github.com/json-iterator/go v1.1.9
 	github.com/valyala/fasthttp v1.9.0
-  	github.com/fasthttp/websocket v1.4.2
 )