bugfix: handle grpc headers

Signed-off-by: Smuu <18609909+Smuu@users.noreply.github.com>

main.go

@@ -63,48 +63,6 @@ func proxyRequest(fullSubdomain, path string, buffer *bytes.Buffer, r *http.Requ
 	return resp.StatusCode, headers, nil
 }
 
-func proxyGrpcRequest(ctx context.Context, fullSubdomain, method string, r *http.Request) (codes.Code, map[string]string, []byte, error) {
-	target := "https://" + fullSubdomain + ".lunaroasis.net" + method
-	conn, err := grpc.Dial(target, grpc.WithInsecure())
-	if err != nil {
-		return 0, nil, nil, err
-	}
-	defer conn.Close()
-
-	stream, err := conn.NewStream(ctx, &grpc.StreamDesc{ServerStreams: true}, method)
-	if err != nil {
-		return 0, nil, nil, err
-	}
-
-	// Assume r.Body is a io.Reader containing the serialized request message
-	if err := stream.SendMsg(r.Body); err != nil {
-		return 0, nil, nil, err
-	}
-
-	// Create a buffer to hold the serialized response message
-	buffer := new(bytes.Buffer)
-	if err := stream.RecvMsg(buffer); err != nil {
-		return 0, nil, nil, err
-	}
-
-	headers, _ := metadata.FromIncomingContext(ctx)
-	headerMap := make(map[string]string)
-	for key, values := range headers {
-		for _, value := range values {
-			headerMap[key] = value
-		}
-	}
-
-	if err := stream.RecvMsg(buffer); err != nil {
-		st, ok := status.FromError(err)
-		if ok {
-			return st.Code(), nil, buffer.Bytes(), err
-		}
-		return codes.Unknown, nil, nil, err
-	}
-	return codes.Unknown, nil, nil, fmt.Errorf("unexpected error")
-}
-
 func handleHttpRequest(w http.ResponseWriter, r *http.Request) {
 	infoLog.Printf("Received request from %s", r.Host)
 	hostParts := strings.Split(r.Host, ".")
@@ -146,6 +104,59 @@ func handleHttpRequest(w http.ResponseWriter, r *http.Request) {
 	io.Copy(w, buffer)
 }
 
+func proxyGrpcRequest(ctx context.Context, fullSubdomain, method string, r *http.Request) (codes.Code, map[string]string, []byte, error) {
+	target := "https://" + fullSubdomain + ".lunaroasis.net" + method
+	conn, err := grpc.Dial(target, grpc.WithInsecure())
+	if err != nil {
+		return 0, nil, nil, err
+	}
+	defer conn.Close()
+
+	// Convert http.Header to map[string]string
+	headerMap := make(map[string]string)
+	for key, values := range r.Header {
+		headerMap[key] = strings.Join(values, ",")
+	}
+
+	// Create metadata from the header map
+	md := metadata.New(headerMap)
+
+	// Create a new outgoing context with the metadata
+	ctx = metadata.NewOutgoingContext(ctx, md)
+
+	stream, err := conn.NewStream(ctx, &grpc.StreamDesc{ServerStreams: true}, method)
+	if err != nil {
+		return 0, nil, nil, err
+	}
+
+	// Assume r.Body is a io.Reader containing the serialized request message
+	if err := stream.SendMsg(r.Body); err != nil {
+		return 0, nil, nil, err
+	}
+
+	// Create a buffer to hold the serialized response message
+	buffer := new(bytes.Buffer)
+	if err := stream.RecvMsg(buffer); err != nil {
+		return 0, nil, nil, err
+	}
+
+	// Collect headers from the gRPC response
+	headers, _ := metadata.FromIncomingContext(ctx)
+	responseHeaderMap := make(map[string]string)
+	for key, values := range headers {
+		responseHeaderMap[key] = strings.Join(values, ",")
+	}
+
+	if err := stream.RecvMsg(buffer); err != nil {
+		st, ok := status.FromError(err)
+		if ok {
+			return st.Code(), nil, buffer.Bytes(), err
+		}
+		return codes.Unknown, nil, nil, err
+	}
+	return codes.Unknown, nil, nil, fmt.Errorf("unexpected error")
+}
+
 func handleGrpcRequest(w http.ResponseWriter, r *http.Request) {
 	infoLog.Printf("Received gRPC request from %s", r.Host)
 	hostParts := strings.Split(r.Host, ".")