server: add server.SetHandlerOption helper

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

server/context.go

@@ -42,3 +42,13 @@ func SetSubscriberOption(k, v interface{}) SubscriberOption {
 		o.Context = context.WithValue(o.Context, k, v)
 	}
 }
+
+// SetHandlerOption returns a function to setup a context with given value
+func SetHandlerOption(k, v interface{}) HandlerOption {
+	return func(o *HandlerOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

server/options.go

@@ -322,7 +322,7 @@ type HandlerOption func(*HandlerOptions)
 type HandlerOptions struct {
 	// Context holds external options
 	Context context.Context
-	// Metadata for hondler
+	// Metadata for handler
 	Metadata map[string]metadata.Metadata
 }