fix(pyra2yr): Race condition in WebSocketClient

In send_message(), when retrieving result from out_queue, another task
could put a message to in_queue, resulting in wrong message to be
retrieved from out_queue.

Fixed by introducing a lock.

Closes #5

pyra2yr/pyra2yr/network.py

@@ -94,6 +94,7 @@ def __init__(self, uri: str, timeout=5.0):
         self.task = None
         self._tries = 15
         self._connect_delay = 1.0
+        self._lock = asyncio.Lock()
 
     def open(self):
         self.task = asyncio.create_task(async_log_exceptions(self.main()))
@@ -103,8 +104,9 @@ async def close(self):
         await self.task
 
     async def send_message(self, m: str) -> aiohttp.WSMessage:
-        await self.in_queue.put(m)
-        return await self.out_queue.get()
+        async with self._lock:
+            await self.in_queue.put(m)
+            return await self.out_queue.get()
 
     async def main(self):
         # send the initial message