Merge pull request #783 from gin-gonic/ip

Update getClientIP()

context.go

@@ -349,13 +349,10 @@ func (c *Context) BindWith(obj interface{}, b binding.Binding) error {
 
 // ClientIP implements a best effort algorithm to return the real client IP, it parses
 // X-Real-IP and X-Forwarded-For in order to work properly with reverse-proxies such us: nginx or haproxy.
+// Use X-Forwarded-For before X-Real-Ip as nginx uses X-Real-Ip with the proxy's IP.
 func (c *Context) ClientIP() string {
 	if c.engine.ForwardedByClientIP {
-		clientIP := strings.TrimSpace(c.requestHeader("X-Real-Ip"))
-		if len(clientIP) > 0 {
-			return clientIP
-		}
-		clientIP = c.requestHeader("X-Forwarded-For")
+		clientIP := c.requestHeader("X-Forwarded-For")
 		if index := strings.IndexByte(clientIP, ','); index >= 0 {
 			clientIP = clientIP[0:index]
 		}
@@ -363,6 +360,10 @@ func (c *Context) ClientIP() string {
 		if len(clientIP) > 0 {
 			return clientIP
 		}
+		clientIP = strings.TrimSpace(c.requestHeader("X-Real-Ip"))
+		if len(clientIP) > 0 {
+			return clientIP
+		}
 	}
 
 	if c.engine.AppEngine {

context_test.go

@@ -718,24 +718,25 @@ func TestContextClientIP(t *testing.T) {
 	c.Request.Header.Set("X-Appengine-Remote-Addr", "50.50.50.50")
 	c.Request.RemoteAddr = "  40.40.40.40:42123 "
 
-	assert.Equal(t, c.ClientIP(), "10.10.10.10")
+	assert.Equal(t, "20.20.20.20", c.ClientIP())
 
-	c.Request.Header.Del("X-Real-IP")
-	assert.Equal(t, c.ClientIP(), "20.20.20.20")
+	c.Request.Header.Del("X-Forwarded-For")
+	assert.Equal(t, "10.10.10.10", c.ClientIP())
 
 	c.Request.Header.Set("X-Forwarded-For", "30.30.30.30  ")
-	assert.Equal(t, c.ClientIP(), "30.30.30.30")
+	assert.Equal(t, "30.30.30.30", c.ClientIP())
 
 	c.Request.Header.Del("X-Forwarded-For")
+	c.Request.Header.Del("X-Real-IP")
 	c.engine.AppEngine = true
-	assert.Equal(t, c.ClientIP(), "50.50.50.50")
+	assert.Equal(t, "50.50.50.50", c.ClientIP())
 
 	c.Request.Header.Del("X-Appengine-Remote-Addr")
-	assert.Equal(t, c.ClientIP(), "40.40.40.40")
+	assert.Equal(t, "40.40.40.40", c.ClientIP())
 
 	// no port
 	c.Request.RemoteAddr = "50.50.50.50"
-	assert.Equal(t, c.ClientIP(), "")
+	assert.Equal(t, "", c.ClientIP())
 }
 
 func TestContextContentType(t *testing.T) {