support bind http header param #1956

README.md

@@ -40,6 +40,7 @@ Gin is a web framework written in Go (Golang). It features a martini-like API wi
     - [Only Bind Query String](#only-bind-query-string)
     - [Bind Query String or Post Data](#bind-query-string-or-post-data)
     - [Bind Uri](#bind-uri)
+    - [Bind Header](#bind-header)
     - [Bind HTML checkboxes](#bind-html-checkboxes)
     - [Multipart/Urlencoded binding](#multiparturlencoded-binding)
     - [XML, JSON, YAML and ProtoBuf rendering](#xml-json-yaml-and-protobuf-rendering)
@@ -910,6 +911,43 @@ $ curl -v localhost:8088/thinkerou/987fbc97-4bed-5078-9f07-9141ba07c9f3
 $ curl -v localhost:8088/thinkerou/not-uuid
 ```
 
+### Bind Header
+
+```go
+package main
+
+import (
+	"fmt"
+	"github.com/gin-gonic/gin"
+)
+
+type testHeader struct {
+	Rate   int    `header:"Rate"`
+	Domain string `header:"Domain"`
+}
+
+func main() {
+	r := gin.Default()
+	r.GET("/", func(c *gin.Context) {
+		h := testHeader{}
+
+		if err := c.ShouldBindHeader(&h); err != nil {
+			c.JSON(200, err)
+		}
+
+		fmt.Printf("%#v\n", h)
+		c.JSON(200, 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)

binding/binding.go

@@ -78,6 +78,7 @@ var (
 	MsgPack       = msgpackBinding{}
 	YAML          = yamlBinding{}
 	Uri           = uriBinding{}
+	Header        = headerBinding{}
 )
 
 // Default returns the appropriate Binding instance based on the HTTP method

binding/binding_test.go

@@ -667,6 +667,31 @@ func TestExistsFails(t *testing.T) {
 	assert.Error(t, err)
 }
 
+func TestHeaderBinding(t *testing.T) {
+	h := Header
+	assert.Equal(t, "header", h.Name())
+
+	type tHeader struct {
+		Limit int `header:"limit"`
+	}
+
+	var theader tHeader
+	req := requestWithBody("GET", "/", "")
+	req.Header.Add("limit", "1000")
+	assert.NoError(t, h.Bind(req, &theader))
+	assert.Equal(t, 1000, theader.Limit)
+
+	req = requestWithBody("GET", "/", "")
+	req.Header.Add("fail", `{fail:fail}`)
+
+	type failStruct struct {
+		Fail map[string]interface{} `header:"fail"`
+	}
+
+	err := h.Bind(req, &failStruct{})
+	assert.Error(t, err)
+}
+
 func TestUriBinding(t *testing.T) {
 	b := Uri
 	assert.Equal(t, "uri", b.Name())

binding/header.go

@@ -0,0 +1,34 @@
+package binding
+
+import (
+	"net/http"
+	"net/textproto"
+	"reflect"
+)
+
+type headerBinding struct{}
+
+func (headerBinding) Name() string {
+	return "header"
+}
+
+func (headerBinding) Bind(req *http.Request, obj interface{}) error {
+
+	if err := mapHeader(obj, req.Header); err != nil {
+		return err
+	}
+
+	return validate(obj)
+}
+
+func mapHeader(ptr interface{}, h map[string][]string) error {
+	return mappingByPtr(ptr, headerSource(h), "header")
+}
+
+type headerSource map[string][]string
+
+var _ setter = headerSource(nil)
+
+func (hs headerSource) TrySet(value reflect.Value, field reflect.StructField, tagValue string, opt setOptions) (isSetted bool, err error) {
+	return setByForm(value, field, hs, textproto.CanonicalMIMEHeaderKey(tagValue), opt)
+}

context.go

@@ -583,6 +583,11 @@ func (c *Context) BindYAML(obj interface{}) error {
 	return c.MustBindWith(obj, binding.YAML)
 }
 
+// BindHeader is a shortcut for c.MustBindWith(obj, binding.Header).
+func (c *Context) BindHeader(obj interface{}) error {
+	return c.MustBindWith(obj, binding.Header)
+}
+
 // BindUri binds the passed struct pointer using binding.Uri.
 // It will abort the request with HTTP 400 if any error occurs.
 func (c *Context) BindUri(obj interface{}) error {
@@ -637,6 +642,11 @@ func (c *Context) ShouldBindYAML(obj interface{}) error {
 	return c.ShouldBindWith(obj, binding.YAML)
 }
 
+// ShouldBindHeader is a shortcut for c.ShouldBindWith(obj, binding.Header).
+func (c *Context) ShouldBindHeader(obj interface{}) error {
+	return c.ShouldBindWith(obj, binding.Header)
+}
+
 // ShouldBindUri binds the passed struct pointer using the specified binding engine.
 func (c *Context) ShouldBindUri(obj interface{}) error {
 	m := make(map[string][]string)

context_test.go

@@ -1436,6 +1436,28 @@ func TestContextBindWithXML(t *testing.T) {
 	assert.Equal(t, 0, w.Body.Len())
 }
 
+func TestContextBindHeader(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+
+	c.Request, _ = http.NewRequest("POST", "/", nil)
+	c.Request.Header.Add("rate", "8000")
+	c.Request.Header.Add("domain", "music")
+	c.Request.Header.Add("limit", "1000")
+
+	var testHeader struct {
+		Rate   int    `header:"Rate"`
+		Domain string `header:"Domain"`
+		Limit  int    `header:"limit"`
+	}
+
+	assert.NoError(t, c.BindHeader(&testHeader))
+	assert.Equal(t, 8000, testHeader.Rate)
+	assert.Equal(t, "music", testHeader.Domain)
+	assert.Equal(t, 1000, testHeader.Limit)
+	assert.Equal(t, 0, w.Body.Len())
+}
+
 func TestContextBindWithQuery(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)
@@ -1543,6 +1565,28 @@ func TestContextShouldBindWithXML(t *testing.T) {
 	assert.Equal(t, 0, w.Body.Len())
 }
 
+func TestContextShouldBindHeader(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+
+	c.Request, _ = http.NewRequest("POST", "/", nil)
+	c.Request.Header.Add("rate", "8000")
+	c.Request.Header.Add("domain", "music")
+	c.Request.Header.Add("limit", "1000")
+
+	var testHeader struct {
+		Rate   int    `header:"Rate"`
+		Domain string `header:"Domain"`
+		Limit  int    `header:"limit"`
+	}
+
+	assert.NoError(t, c.ShouldBindHeader(&testHeader))
+	assert.Equal(t, 8000, testHeader.Rate)
+	assert.Equal(t, "music", testHeader.Domain)
+	assert.Equal(t, 1000, testHeader.Limit)
+	assert.Equal(t, 0, w.Body.Len())
+}
+
 func TestContextShouldBindWithQuery(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)