TMSS-556: Add first skeleton of WebSocket class to handle auth

SAS/TMSS/backend/services/websocket/lib/websocket_service.py

@@ -44,6 +44,23 @@ HTTP Headers are not supported inside the WebSocket protocol (see https://tools.
 WS traffic is either UTC-8 text or binary data (see https://tools.ietf.org/html/rfc6455#page-39).
 '''
 
+
+class TMSSWebSocket(WebSocket):
+    authenticated = False
+    # TODO: Handle list of connected clients.
+
+    def handleMessage(self):
+        if not self.authenticated:  # Not (yet) authenticated
+            token = json.loads(self.data).get('token', '')
+            self.authenticated = True  # TODO: Check if token is valid.
+            if not self.authenticated:
+                logging.info('> Client unauthenticated %s' % self.address[0])
+                self.close(1011, u'unauthenticated')
+            else:
+                logging.info('> Client authenticated %s' % self.address[0])
+                self.sendMessage('Successfully authenticated.')
+
+
 class TMSSEventMessageHandlerForWebsocket(TMSSEventMessageHandler):
     '''
     '''
@@ -71,7 +88,7 @@ class TMSSEventMessageHandlerForWebsocket(TMSSEventMessageHandler):
         # Create and run a simple ws server
         def start_ws_server():
             logger.debug("starting websocket server on port %s", self.websocket_port)
-            self._ws_server = SimpleWebSocketServer('', self.websocket_port, WebSocket)
+            self._ws_server = SimpleWebSocketServer('', self.websocket_port, TMSSWebSocket)
             socket_started_event.set()
             logger.info("started websocket server on port %s", self.websocket_port)
             while self._run_ws: # Run the server till the stop_handling
@@ -100,6 +117,7 @@ class TMSSEventMessageHandlerForWebsocket(TMSSEventMessageHandler):
             try:
                 model_class = apps.get_model("tmssapp", object_type.value.replace('_',''))
                 model_instance = model_class.objects.get(id=id)
+                # TODO: Check user permissions for the model_instance.
                 if hasattr(model_instance, 'process_start_time') and model_instance.process_start_time is not None:
                     json_blob['object_details']['process_start_time'] = model_instance.process_start_time.isoformat()
                 if hasattr(model_instance, 'process_stop_time') and model_instance.process_stop_time is not None: