diff --git a/signer/core/api.go b/signer/core/api.go
index 12acf925f0..3b7b53a312 100644
--- a/signer/core/api.go
+++ b/signer/core/api.go
@@ -196,8 +196,9 @@ func MetadataFromContext(ctx context.Context) Metadata {
 	if info.Transport != "" {
 		if info.Transport == "http" {
 			m.Scheme = info.HTTP.Version
+		} else {
+			m.Scheme = info.Transport
 		}
-		m.Scheme = info.Transport
 	}
 	if info.RemoteAddr != "" {
 		m.Remote = info.RemoteAddr