From fd5ed6472923624f63b584b6287c6ec4ddceced8 Mon Sep 17 00:00:00 2001
From: Vasiliy Tolstov <v.tolstov@unistack.org>
Date: Fri, 12 Feb 2021 17:10:35 +0300
Subject: [PATCH] metadata: fix nil metadata from FromIncoming/FromOutgoing
 context

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
---
 metadata/context.go       | 6 +++---
 metadata/metadata_test.go | 5 +++--
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/metadata/context.go b/metadata/context.go
index b7540c14..482d801a 100644
--- a/metadata/context.go
+++ b/metadata/context.go
@@ -16,7 +16,7 @@ func FromIncomingContext(ctx context.Context) (Metadata, bool) {
 		return nil, false
 	}
 	md, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata)
-	if !ok {
+	if !ok || md.md == nil {
 		return nil, false
 	}
 	return md.md, ok
@@ -29,7 +29,7 @@ func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
 		return nil, false
 	}
 	md, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata)
-	if !ok {
+	if !ok || md.md == nil {
 		return nil, false
 	}
 	return md.md, ok
@@ -44,7 +44,7 @@ func FromContext(ctx context.Context) (Metadata, bool) {
 		return nil, false
 	}
 	md, ok := ctx.Value(mdKey{}).(*rawMetadata)
-	if !ok {
+	if !ok || md.md == nil {
 		return nil, false
 	}
 	return md.md, ok
diff --git a/metadata/metadata_test.go b/metadata/metadata_test.go
index d1b91efb..f580f5aa 100644
--- a/metadata/metadata_test.go
+++ b/metadata/metadata_test.go
@@ -2,7 +2,6 @@ package metadata
 
 import (
 	"context"
-	"fmt"
 	"testing"
 )
 
@@ -25,7 +24,9 @@ func TestPassing(t *testing.T) {
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
 	}
-	fmt.Printf("%#+v\n", md)
+	if v, ok := md.Get("Key1"); !ok || v != "Val1_new" {
+		t.Fatalf("invalid metadata value %#+v", md)
+	}
 }
 
 func TestMerge(t *testing.T) {