Prevent unwanted events transmitted to UI (while T2 under development).

Change-Id: Ib96e01bd0992684429e048421c18a24bd11e4a92
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
index 0290857..328207d 100644
--- a/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
@@ -95,7 +95,12 @@
         Topo2Jsonifier t2json = new Topo2Jsonifier(directory);
         UiSharedTopologyModel sharedModel = directory.get(UiSharedTopologyModel.class);
         UiTopoLayoutService layoutService = directory.get(UiTopoLayoutService.class);
-        this.topoSession = new UiTopoSession(this, t2json, sharedModel, layoutService);
+
+        topoSession = new UiTopoSession(this, t2json, sharedModel, layoutService);
+
+        // FIXME: this is temporary to prevent unhandled events being set to GUI...
+        //         while Topo2 is still under development
+        topoSession.enableEvent(false);
     }
 
     @Override
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/UiTopoSession.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/UiTopoSession.java
index f13ebc5..288a343 100644
--- a/web/gui/src/main/java/org/onosproject/ui/impl/topo/UiTopoSession.java
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/UiTopoSession.java
@@ -66,7 +66,7 @@
 
     private UiTopoLayoutService layoutService;
     private UiTopoLayout currentLayout;
-    private boolean messagesEnabled;
+    private boolean messagesEnabled = true;
 
     /**
      * Creates a new topology session for the specified web socket connection,
@@ -130,16 +130,22 @@
 
     @Override
     public void event(UiModelEvent event) {
-        log.debug("Event received: {}", event);
-        ObjectNode payload = t2json.jsonEvent(event);
+        String msg = messagesEnabled
+                ? "Event received: {}"
+                : "Event received: {}, but not transmitted";
+        log.debug(msg, event);
 
-        // TODO: add filtering for relevant objects only...
-        // TO Decide: Since the session holds the state of what is being
-        //   displayed on the client, we should filter out any model events
-        //   that are not relevant, and only send up events for objects that
-        //   are currently being viewed by the user.
+        if (messagesEnabled) {
+            ObjectNode payload = t2json.jsonEvent(event);
 
-        webSocket.sendMessage(TOPO2_UI_MODEL_EVENT, payload);
+            // TODO: add filtering for relevant objects only...
+            // TO Decide: Since the session holds the state of what is being
+            //   displayed on the client, we should filter out any model events
+            //   that are not relevant, and only send up events for objects that
+            //   are currently being viewed by the user.
+
+            webSocket.sendMessage(TOPO2_UI_MODEL_EVENT, payload);
+        }
     }
 
     /**