fix: Mitigate gateway null responses. (#1053)

* fix: Handle gateway stream when None is given.

* refactor: Change occurrence of heartbeater task recreation

(This just mitigates an edgecase of heartbeating when the wsclient is None.

* chore: pre-commit ci

Author: FayeDel

interactions/api/gateway/client.py

@@ -262,7 +262,8 @@ async def run(self) -> None:
                 _receive.cancel()
                 return
 
-            await self._handle_stream(msg)
+            if msg is not None:  # this can happen
+                await self._handle_stream(msg)
 
     async def _handle_stream(self, stream: Dict[str, Any]):
         """
@@ -710,6 +711,13 @@ async def _reconnect(self, to_resume: bool, code: Optional[int] = 1012) -> None:
 
             self._client = None
 
+            # We need to check about existing heartbeater tasks for edge cases.
+
+            if self._task:
+                self._task.cancel()
+                if self.__heartbeat_event.is_set():
+                    self.__heartbeat_event.clear()  # Because we're hardresetting the process
+
             if not to_resume:
                 url = self.ws_url if self.ws_url else await self._http.get_gateway()
             else:
@@ -721,12 +729,7 @@ async def _reconnect(self, to_resume: bool, code: Optional[int] = 1012) -> None:
 
             self.__heartbeater.delay = data["d"]["heartbeat_interval"]
 
-            if self._task:
-                self._task.cancel()
-                if self.__heartbeat_event.is_set():
-                    self.__heartbeat_event.clear()  # Because we're hardresetting the process
-
-                self._task = create_task(self.run_heartbeat())
+            self._task = create_task(self.run_heartbeat())
 
             if not to_resume:
                 await self.__identify(self.__shard, self.__presence)
@@ -800,7 +803,19 @@ async def __receive_packet(self, ignore_lock: bool = False) -> Optional[Dict[str
             if packet.data is None:
                 continue  # We just loop it over because it could just be processing something.
 
-            return loads(packet.data) if isinstance(packet.data, str) else None
+            try:
+                msg = loads(packet.data)
+            except Exception as e:
+                import traceback
+
+                log.debug(
+                    f'Error serialising message: {"".join(traceback.format_exception(type(e), e, e.__traceback__))}.'
+                )
+                # There's an edge case when the packet's None... or some other deserialisation error.
+                # Instead of raising an exception, we just log it to debug, so it doesn't annoy end user's console logs.
+                msg = None
+
+            return msg
 
     async def _send_packet(self, data: Dict[str, Any]) -> None:
         """