Revert "work around a memory leak in channels_redis"

This reverts commit e25da217e8.

awx/main/consumers.py

@@ -1,5 +1,3 @@
-import collections
-import functools
 import json
 import logging
 import time
@@ -14,40 +12,12 @@ from django.contrib.auth.models import User
 from channels.generic.websocket import AsyncJsonWebsocketConsumer
 from channels.layers import get_channel_layer
 from channels.db import database_sync_to_async
-from channels_redis.core import RedisChannelLayer
 
 
 logger = logging.getLogger('awx.main.consumers')
 XRF_KEY = '_auth_user_xrf'
 
 
-class BoundedQueue(asyncio.Queue):
-
-    def put_nowait(self, item):
-        if self.full():
-            # dispose the oldest item
-            # if we actually get into this code block, it likely means that
-            # this specific consumer has stopped reading
-            # unfortunately, channels_redis will just happily continue to
-            # queue messages specific to their channel until the heat death
-            # of the sun: https://github.com/django/channels_redis/issues/212
-            # this isn't a huge deal for browser clients that disconnect,
-            # but it *does* cause a problem for our global broadcast topic
-            # that's used to broadcast messages to peers in a cluster
-            # if we get into this code block, it's better to drop messages
-            # than to continue to malloc() forever
-            self.get_nowait()
-        return super(BoundedQueue, self).put_nowait(item)
-
-
-class ExpiringRedisChannelLayer(RedisChannelLayer):
-    def __init__(self, *args, **kw):
-        super(ExpiringRedisChannelLayer, self).__init__(*args, **kw)
-        self.receive_buffer = collections.defaultdict(
-            functools.partial(BoundedQueue, self.capacity)
-        )
-
-
 class WebsocketSecretAuthHelper:
     """
     Middlewareish for websockets to verify node websocket broadcast interconnect.

awx/settings/defaults.py

@@ -790,7 +790,7 @@ ASGI_APPLICATION = "awx.main.routing.application"
 
 CHANNEL_LAYERS = {
     "default": {
-        "BACKEND": "awx.main.consumers.ExpiringRedisChannelLayer",
+        "BACKEND": "channels_redis.core.RedisChannelLayer",
         "CONFIG": {
             "hosts": [BROKER_URL],
             "capacity": 10000,