update for supporting file binding

binding/binding.go

@@ -69,6 +69,8 @@ func Default(method, contentType string) Binding {
 		return ProtoBuf
 	case MIMEMSGPACK, MIMEMSGPACK2:
 		return MsgPack
+	case MIMEMultipartPOSTForm:
+		return FormMultipart
 	default: //case MIMEPOSTForm, MIMEMultipartPOSTForm:
 		return Form
 	}

binding/binding_test.go

@@ -8,9 +8,11 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"io"
 	"io/ioutil"
 	"mime/multipart"
 	"net/http"
+	"os"
 	"testing"
 	"time"
 
@@ -29,6 +31,18 @@ type FooBarStruct struct {
 	Bar string `msgpack:"bar" json:"bar" form:"bar" xml:"bar" binding:"required"`
 }
 
+type FooBarFileStruct struct {
+	FooBarStruct
+	File *multipart.FileHeader `form:"file" binding:"required"`
+}
+
+type FooBarFileFailStruct struct {
+	FooBarStruct
+	File *multipart.FileHeader `invalid_name:"file" binding:"required"`
+	// for unexport test
+	data *multipart.FileHeader `form:"data" binding:"required"`
+}
+
 type FooStructUseNumber struct {
 	Foo interface{} `json:"foo" binding:"required"`
 }
@@ -152,8 +166,8 @@ func TestBindingDefault(t *testing.T) {
 	assert.Equal(t, Default("POST", MIMEPOSTForm), Form)
 	assert.Equal(t, Default("PUT", MIMEPOSTForm), Form)
 
-	assert.Equal(t, Default("POST", MIMEMultipartPOSTForm), Form)
+	assert.Equal(t, Default("POST", MIMEMultipartPOSTForm), FormMultipart)
-	assert.Equal(t, Default("PUT", MIMEMultipartPOSTForm), Form)
+	assert.Equal(t, Default("PUT", MIMEMultipartPOSTForm), FormMultipart)
 
 	assert.Equal(t, Default("POST", MIMEPROTOBUF), ProtoBuf)
 	assert.Equal(t, Default("PUT", MIMEPROTOBUF), ProtoBuf)
@@ -413,6 +427,48 @@ func createFormPostRequestFail() *http.Request {
 	return req
 }
 
+func createFormFilesMultipartRequest() *http.Request {
+	boundary := "--testboundary"
+	body := new(bytes.Buffer)
+	mw := multipart.NewWriter(body)
+	defer mw.Close()
+
+	mw.SetBoundary(boundary)
+	mw.WriteField("foo", "bar")
+	mw.WriteField("bar", "foo")
+
+	f, _ := os.Open("form.go")
+	defer f.Close()
+	fw, _ := mw.CreateFormFile("file", "form.go")
+	io.Copy(fw, f)
+
+	req, _ := http.NewRequest("POST", "/?foo=getfoo&bar=getbar", body)
+	req.Header.Set("Content-Type", MIMEMultipartPOSTForm+"; boundary="+boundary)
+
+	return req
+}
+
+func createFormFilesMultipartRequestFail() *http.Request {
+	boundary := "--testboundary"
+	body := new(bytes.Buffer)
+	mw := multipart.NewWriter(body)
+	defer mw.Close()
+
+	mw.SetBoundary(boundary)
+	mw.WriteField("foo", "bar")
+	mw.WriteField("bar", "foo")
+
+	f, _ := os.Open("form.go")
+	defer f.Close()
+	fw, _ := mw.CreateFormFile("file_foo", "form_foo.go")
+	io.Copy(fw, f)
+
+	req, _ := http.NewRequest("POST", "/?foo=getfoo&bar=getbar", body)
+	req.Header.Set("Content-Type", MIMEMultipartPOSTForm+"; boundary="+boundary)
+
+	return req
+}
+
 func createFormMultipartRequest() *http.Request {
 	boundary := "--testboundary"
 	body := new(bytes.Buffer)
@@ -457,6 +513,34 @@ func TestBindingFormPostFail(t *testing.T) {
 	assert.Error(t, err)
 }
 
+func TestBindingFormFilesMultipart(t *testing.T) {
+	req := createFormFilesMultipartRequest()
+	var obj FooBarFileStruct
+	FormMultipart.Bind(req, &obj)
+
+	// file from os
+	f, _ := os.Open("form.go")
+	defer f.Close()
+	fileActual, _ := ioutil.ReadAll(f)
+
+	// file from multipart
+	mf, _ := obj.File.Open()
+	defer mf.Close()
+	fileExpect, _ := ioutil.ReadAll(mf)
+
+	assert.Equal(t, FormMultipart.Name(), "multipart/form-data")
+	assert.Equal(t, obj.Foo, "bar")
+	assert.Equal(t, obj.Bar, "foo")
+	assert.Equal(t, fileExpect, fileActual)
+}
+
+func TestBindingFormFilesMultipartFail(t *testing.T) {
+	req := createFormFilesMultipartRequestFail()
+	var obj FooBarFileFailStruct
+	err := FormMultipart.Bind(req, &obj)
+	assert.Error(t, err)
+}
+
 func TestBindingFormMultipart(t *testing.T) {
 	req := createFormMultipartRequest()
 	var obj FooBarStruct

binding/form.go

@@ -52,5 +52,10 @@ func (formMultipartBinding) Bind(req *http.Request, obj interface{}) error {
 	if err := mapForm(obj, req.MultipartForm.Value); err != nil {
 		return err
 	}
+
+	if err := mapFiles(obj, req); err != nil {
+		return err
+	}
+
 	return validate(obj)
 }

binding/form_mapping.go

@@ -6,11 +6,41 @@ package binding
 
 import (
 	"errors"
+	"fmt"
+	"net/http"
 	"reflect"
 	"strconv"
 	"time"
 )
 
+func mapFiles(ptr interface{}, req *http.Request) error {
+	typ := reflect.TypeOf(ptr).Elem()
+	val := reflect.ValueOf(ptr).Elem()
+	for i := 0; i < typ.NumField(); i++ {
+		typeField := typ.Field(i)
+		structField := val.Field(i)
+
+		t := fmt.Sprintf("%s", typeField.Type)
+		if string(t) != "*multipart.FileHeader" {
+			continue
+		}
+
+		inputFieldName := typeField.Tag.Get("form")
+		if inputFieldName == "" {
+			inputFieldName = typeField.Name
+		}
+
+		_, fileHeader, err := req.FormFile(inputFieldName)
+		if err != nil {
+			return err
+		}
+
+		structField.Set(reflect.ValueOf(fileHeader))
+
+	}
+	return nil
+}
+
 func mapForm(ptr interface{}, form map[string][]string) error {
 	typ := reflect.TypeOf(ptr).Elem()
 	val := reflect.ValueOf(ptr).Elem()