feat: use forwardResponseOption for gateway HTTP redirection (#22)

* feat: use forwardResponseOption for gateway HTTP redirection

* fix: duplicate imports and add TODO comment

Co-authored-by: alok <aloknerurkar@no-reply.com>

go.mod

@@ -37,6 +37,7 @@ require (
 	github.com/slok/go-http-metrics v0.9.0
 	go.uber.org/fx v1.16.0
 	google.golang.org/grpc v1.42.0
+	google.golang.org/protobuf v1.27.1
 )
 
 require (
@@ -203,7 +204,6 @@ require (
 	golang.org/x/tools v0.1.7 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	google.golang.org/genproto v0.0.0-20210602131652-f16073e35f0c // indirect
-	google.golang.org/protobuf v1.27.1 // indirect
 	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
 	lukechampine.com/blake3 v1.1.7 // indirect

modules/node/http/http.go

@@ -12,6 +12,7 @@ import (
 	"github.com/plexsysio/go-msuite/modules/diag/status"
 	"github.com/plexsysio/go-msuite/utils"
 	"go.uber.org/fx"
+	"google.golang.org/protobuf/proto"
 )
 
 var log = logger.Logger("http")
@@ -42,8 +43,22 @@ func NewHTTPServerMux() *nhttp.ServeMux {
 	return nhttp.NewServeMux()
 }
 
+// HTTP redirect handler for gRPC gateway methods
+// TODO: maybe provide a way to configure these options using main Options
+func responseHeaderMatcher(_ context.Context, w nhttp.ResponseWriter, _ proto.Message) error {
+	headers := w.Header()
+	if location, ok := headers["Grpc-Metadata-Location"]; ok {
+		w.Header().Set("Location", location[0])
+		w.WriteHeader(nhttp.StatusFound)
+	}
+
+	return nil
+}
+
 func NewGRPCGateway() *runtime.ServeMux {
-	return runtime.NewServeMux()
+	return runtime.NewServeMux(
+		runtime.WithForwardResponseOption(responseHeaderMatcher),
+	)
 }
 
 type httpReporter struct {