From 9ffd83af7d38ea35ecd621b2e06ee1f8b3eac13b Mon Sep 17 00:00:00 2001
From: Livio Amstutz <livio.a@gmail.com>
Date: Wed, 27 Apr 2022 10:10:54 +0200
Subject: [PATCH] fix: header matcher of grpc-web route (#3524)

---
 internal/api/api.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/internal/api/api.go b/internal/api/api.go
index 64859dce58..6a29364266 100644
--- a/internal/api/api.go
+++ b/internal/api/api.go
@@ -98,7 +98,13 @@ func (a *API) routeGRPC() {
 }
 
 func (a *API) routeGRPCWeb(router *mux.Router) {
-	router.NewRoute().HeadersRegexp("Content-Type", "application/grpc-web.*").Handler(
+	router.NewRoute().MatcherFunc(
+		func(r *http.Request, _ *mux.RouteMatch) bool {
+			if strings.Contains(r.Header.Get("content-type"), "application/grpc-web+") {
+				return true
+			}
+			return strings.Contains(r.Header.Get("access-control-request-headers"), "x-grpc-web")
+		}).Handler(
 		grpcweb.WrapServer(a.grpcServer,
 			grpcweb.WithAllowedRequestHeaders(
 				[]string{