feat: adds cookie binding

.gitignore

@@ -5,3 +5,4 @@ count.out
 test
 profile.out
 tmp.out
+.idea

binding/binding.go

@@ -85,6 +85,7 @@ var (
 	Uri           = uriBinding{}
 	Header        = headerBinding{}
 	TOML          = tomlBinding{}
+	Cookie        = cookieBinding{}
 )
 
 // Default returns the appropriate Binding instance based on the HTTP method

binding/cookie.go

@@ -0,0 +1,22 @@
+// Copyright 2017 Manu Martinez-Almeida. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package binding
+
+import "net/http"
+
+type cookieBinding struct{}
+
+func (cookieBinding) Name() string {
+	return "cookie"
+}
+
+func (c cookieBinding) Bind(req *http.Request, obj any) error {
+	cookies := make(map[string][]string, len(req.Cookies()))
+	for _, cookie := range req.Cookies() {
+		cookies[cookie.Name] = append(cookies[cookie.Name], cookie.Value)
+	}
+
+	return mapFormByTag(obj, cookies, c.Name())
+}

context.go

@@ -726,6 +726,11 @@ func (c *Context) ShouldBindHeader(obj any) error {
 	return c.ShouldBindWith(obj, binding.Header)
 }
 
+// ShouldBindCookie is a shortcut for c.ShouldBindWith(obj, binding.Cookie).
+func (c *Context) ShouldBindCookie(obj any) error {
+	return c.ShouldBindWith(obj, binding.Cookie)
+}
+
 // ShouldBindUri binds the passed struct pointer using the specified binding engine.
 func (c *Context) ShouldBindUri(obj any) error {
 	m := make(map[string][]string)

context_test.go

@@ -1802,6 +1802,27 @@ func TestContextShouldBindHeader(t *testing.T) {
 	assert.Equal(t, 0, w.Body.Len())
 }
 
+func TestContextShouldBindCookie(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+
+	c.Request, _ = http.NewRequest("POST", "/", nil)
+	c.Request.AddCookie(&http.Cookie{Name: "rate", Value: "8000"})
+	c.Request.AddCookie(&http.Cookie{Name: "domain", Value: "music"})
+	c.Request.AddCookie(&http.Cookie{Name: "limit", Value: "1000"})
+
+	var testCookie struct {
+		Rate   int    `cookie:"rate"`
+		Domain string `cookie:"domain"`
+		Limit  int    `cookie:"limit"`
+	}
+
+	assert.NoError(t, c.ShouldBindCookie(&testCookie))
+	assert.Equal(t, 8000, testCookie.Rate)
+	assert.Equal(t, "music", testCookie.Domain)
+	assert.Equal(t, 1000, testCookie.Limit)
+}
+
 func TestContextShouldBindWithQuery(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)

docs/doc.md

@@ -28,6 +28,7 @@
   - [Bind Query String or Post Data](#bind-query-string-or-post-data)
   - [Bind Uri](#bind-uri)
   - [Bind Header](#bind-header)
+  - [Bind Cookie](#bind-cookie)
   - [Bind HTML checkboxes](#bind-html-checkboxes)
   - [Multipart/Urlencoded binding](#multiparturlencoded-binding)
   - [XML, JSON, YAML, TOML and ProtoBuf rendering](#xml-json-yaml-toml-and-protobuf-rendering)
@@ -900,6 +901,45 @@ func main() {
 }
 ```
 
+### Bind Cookie
+
+```go
+package main
+
+import (
+  "fmt"
+  "net/http"
+
+  "github.com/gin-gonic/gin"
+)
+
+type testCookie struct {
+  Rate   int    `cookie:"Rate"`
+  Domain string `cookie:"Domain"`
+}
+
+func main() {
+  r := gin.Default()
+  r.GET("/", func(c *gin.Context) {
+    h := testCookie{}
+
+    if err := c.ShouldBindCookie(&h); err != nil {
+      c.JSON(http.StatusOK, err)
+    }
+
+    fmt.Printf("%#v\n", h)
+    c.JSON(http.StatusOK, gin.H{"Rate": h.Rate, "Domain": h.Domain})
+  })
+
+  r.Run()
+
+// client
+// curl -H "rate:300" -H "domain:music" 127.0.0.1:8080/
+// output
+// {"Domain":"music","Rate":300}
+}
+```
+
 ### Bind HTML checkboxes
 
 See the [detail information](https://github.com/gin-gonic/gin/issues/129#issuecomment-124260092)