small fix to websocketchannel and relay

freqtrade/rpc/api_server/ws/channel.py

@@ -77,6 +77,7 @@ class WebSocketChannel:
         # until self.drain_timeout for the relay to drain the outgoing queue
         # We can't use asyncio.wait_for here because the queue may have been created with a
         # different eventloop
+        if not self.is_closed():
             start = time.time()
             while self.queue.full():
                 await asyncio.sleep(1)
@@ -91,6 +92,8 @@ class WebSocketChannel:
 
             # If we got here everything is ok
             return True
+        else:
+            return False
 
     async def recv(self):
         """
@@ -109,14 +112,14 @@ class WebSocketChannel:
         Close the WebSocketChannel
         """
 
+        self._closed.set()
+        self._relay_task.cancel()
+
         try:
             await self.raw_websocket.close()
         except Exception:
             pass
 
-        self._closed.set()
-        self._relay_task.cancel()
-
     def is_closed(self) -> bool:
         """
         Closed flag