From 94dee576bfda2e05a8feaadb82fffc23c196ce57 Mon Sep 17 00:00:00 2001
From: fan <fancg@outlook.com>
Date: Sun, 5 May 2019 19:04:54 +0800
Subject: [PATCH] add support http forward

---
 context.go      | 21 +++++++++++++++++++++
 context_test.go | 38 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/context.go b/context.go
index 5dc7f8a0..db18187b 100644
--- a/context.go
+++ b/context.go
@@ -13,6 +13,7 @@ import (
 	"mime/multipart"
 	"net"
 	"net/http"
+	"net/http/httputil"
 	"net/url"
 	"os"
 	"strings"
@@ -1026,3 +1027,23 @@ func (c *Context) Value(key interface{}) interface{} {
 	}
 	return nil
 }
+
+// ReverseProxy is an HTTP Handler that takes an incoming request and
+// sends it to another server, proxying the response back to the client.
+// You can use it to forward.
+func (c *Context) Forward(target string) {
+	host := c.Request.Host
+	scheme := c.Request.URL.Scheme
+	if scheme == "" {
+		scheme = "http"
+	}
+	var proxy = httputil.ReverseProxy{
+		Director: func(req *http.Request) {
+			req.URL.Scheme = scheme
+			req.URL.Host = host
+			req.Host = host
+		},
+	}
+	c.Request.URL.Path = target
+	proxy.ServeHTTP(c.Writer, c.Request)
+}
diff --git a/context_test.go b/context_test.go
index 0da5fbe6..43b7499a 100644
--- a/context_test.go
+++ b/context_test.go
@@ -10,21 +10,22 @@ import (
 	"fmt"
 	"html/template"
 	"io"
+	"io/ioutil"
 	"mime/multipart"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
 	"github.com/gin-contrib/sse"
 	"github.com/gin-gonic/gin/binding"
+	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 	"github.com/golang/protobuf/proto"
 	"github.com/stretchr/testify/assert"
 	"golang.org/x/net/context"
-
-	testdata "github.com/gin-gonic/gin/testdata/protoexample"
 )
 
 var _ context.Context = &Context{}
@@ -1812,3 +1813,36 @@ func TestContextResetInHandler(t *testing.T) {
 		c.Next()
 	})
 }
+
+func TestContext_Forward(t *testing.T) {
+	g := sync.WaitGroup{}
+	g.Add(1)
+	go func(g *sync.WaitGroup) {
+		g.Done()
+		e := Default()
+		e.GET("/test", func(c *Context) {
+			c.Forward("/test2")
+		})
+		e.GET("/test2", func(c *Context) {
+			p := c.Query("p")
+			c.String(http.StatusOK, p)
+
+		})
+		e.Run(":9998")
+
+	}(&g)
+
+	g.Wait()
+
+	p := "test"
+	resp, err := http.Get("http://127.0.0.1:9998/test?p=" + p)
+	assert.NoError(t, err)
+	defer resp.Body.Close()
+
+	bytes, err := ioutil.ReadAll(resp.Body)
+
+	assert.NoError(t, err)
+
+	assert.Equal(t, p, string(bytes))
+
+}