error handle by non-json formatted s3i messages

ml/thing.py

@@ -449,24 +449,27 @@ def __on_broker_callback(self, ch, method, properties, body):
                 pass
 
         elif isinstance(body, int):
-            return
+            pass
         elif isinstance(body, str):
-            return
+            pass
 
-        ch.basic_ack(method.delivery_tag)
-        message_type = body.get("messageType")
-        if message_type == "userMessage":
-            self.on_user_message(body)
-        elif message_type == "serviceRequest":
-            self.on_service_request(body)
-        elif message_type == "getValueRequest":
-            self.on_get_value_request(body)
-        elif message_type == "getValueReply":
-            self.on_get_value_reply(body)
-        elif message_type == "serviceReply":
-            self.on_service_reply(body)
-        else:
-            ### TODO send user message reply back
+        self.broker.receiver.acknowledge_message(method.delivery_tag)
+        try:
+            message_type = body.get("messageType")
+            if message_type == "userMessage":
+                self.on_user_message(body)
+            elif message_type == "serviceRequest":
+                self.on_service_request(body)
+            elif message_type == "getValueRequest":
+                self.on_get_value_request(body)
+            elif message_type == "getValueReply":
+                self.on_get_value_reply(body)
+            elif message_type == "serviceReply":
+                self.on_service_reply(body)
+            else:
+                ### TODO send user message reply back
+                pass
+        except AttributeError:
             pass
 
     def __send_message_to_broker(self, receiver_endpoints, msg):