add the "new_topic" param to the open message

server/message_cache_test.go

@@ -32,8 +32,8 @@ func testCacheMessages(t *testing.T, c *messageCache) {
 	require.Nil(t, c.AddMessage(m2))
 
 	// Adding invalid
-	require.Equal(t, errUnexpectedMessageType, c.AddMessage(newKeepaliveMessage("mytopic"))) // These should not be added!
-	require.Equal(t, errUnexpectedMessageType, c.AddMessage(newOpenMessage("example")))      // These should not be added!
+	require.Equal(t, errUnexpectedMessageType, c.AddMessage(newKeepaliveMessage("mytopic")))   // These should not be added!
+	require.Equal(t, errUnexpectedMessageType, c.AddMessage(newOpenMessage("example", false))) // These should not be added!
 
 	// mytopic: count
 	counts, err := c.MessageCounts()

server/server_firebase_test.go

@@ -92,7 +92,7 @@ func TestToFirebaseMessage_Keepalive(t *testing.T) {
 }
 
 func TestToFirebaseMessage_Open(t *testing.T) {
-	m := newOpenMessage("mytopic")
+	m := newOpenMessage("mytopic", false)
 	fbm, err := toFirebaseMessage(m, nil)
 	require.Nil(t, err)
 	require.Equal(t, "mytopic", fbm.Topic)

server/types.go

@@ -17,6 +17,7 @@ const (
 	keepaliveEvent   = "keepalive"
 	messageEvent     = "message"
 	pollRequestEvent = "poll_request"
+	createdNewTopicParameter = "new_topic"
 )
 
 const (
@@ -123,8 +124,12 @@ func newMessage(event, topic, msg string) *message {
 }
 
 // newOpenMessage is a convenience method to create an open message
-func newOpenMessage(topic string) *message {
-	return newMessage(openEvent, topic, "")
+func newOpenMessage(topic string, createdNewTopics bool) *message {
+	msg := ""
+	if createdNewTopics { // can expand this to a comma seperated string for more future parameters
+		msg = createdNewTopicParameter
+	}
+	return newMessage(openEvent, topic, msg)
 }
 
 // newKeepaliveMessage is a convenience method to create a keepalive message