From d54e4fa28f8f145587416ab30dd9bea1b300165a Mon Sep 17 00:00:00 2001
From: snoop <snoop@loafle.com>
Date: Thu, 8 Jun 2017 10:53:32 +0900
Subject: [PATCH] fixed   cors

---
 server/gwrpc.go | 31 +++++++++++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/server/gwrpc.go b/server/gwrpc.go
index 8ca0ce5..d0d82c2 100644
--- a/server/gwrpc.go
+++ b/server/gwrpc.go
@@ -7,10 +7,12 @@ import (
 	"google.golang.org/grpc"
 	pb "git.loafle.net/overflow/overflow_api_service/grpc"
 	"net/http"
+	"strings"
+	"github.com/golang/glog"
 )
 
 var (
-	overflowEndpoint = flag.String("echo_endpoint", "localhost:9090", "/v1/overflow/services")
+	overflowEndpoint = flag.String("echo_endpoint", ":9090", "/v1/overflow/services")
 )
 
 func RunGwRpc() (err error) {
@@ -27,5 +29,30 @@ func RunGwRpc() (err error) {
 		return err
 	}
 
-	return http.ListenAndServe(":8080", mux)
+	return http.ListenAndServe(":8080", allowCORS(mux))
+}
+
+
+//https://github.com/grpc-ecosystem/grpc-gateway/blob/master/examples/main.go
+
+func allowCORS(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if origin := r.Header.Get("Origin"); origin != "" {
+			w.Header().Set("Access-Control-Allow-Origin", origin)
+			if r.Method == "OPTIONS" && r.Header.Get("Access-Control-Request-Method") != "" {
+				preflightHandler(w, r)
+				return
+			}
+		}
+		h.ServeHTTP(w, r)
+	})
+}
+
+func preflightHandler(w http.ResponseWriter, r *http.Request) {
+	headers := []string{"Content-Type", "Accept"}
+	w.Header().Set("Access-Control-Allow-Headers", strings.Join(headers, ","))
+	methods := []string{"GET", "HEAD", "POST", "PUT", "DELETE"}
+	w.Header().Set("Access-Control-Allow-Methods", strings.Join(methods, ","))
+	glog.Infof("preflight request for %s", r.URL.Path)
+	return
 }
\ No newline at end of file