废弃 huey，多数据库连接的时候存在 connection 无法释放的问题，回到 celery

oj/settings.py

@@ -10,7 +10,7 @@ https://docs.djangoproject.com/en/1.8/topics/settings/
 For the full list of settings and their values, see
 https://docs.djangoproject.com/en/1.8/ref/settings/
 """
-
+from __future__ import absolute_import
 # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
 import os
 
@@ -22,6 +22,9 @@ if ENV == "local":
 elif ENV == "server":
     from .server_settings import *
 
+import djcelery
+djcelery.setup_loader()
+
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 
 
@@ -53,7 +56,7 @@ INSTALLED_APPS = (
     'judge_dispatcher',
 
     'rest_framework',
-    'huey.djhuey',
+    'djcelery',
 )
 
 if DEBUG:
@@ -186,14 +189,6 @@ WEBSITE_INFO = {"website_name": "qduoj",
                 "website_footer": u"青岛大学信息工程学院 创新实验室 <a href=\"http://www.miibeian.gov.cn/\">京ICP备15062075号-1</a>",
                 "url": "https://qduoj.com"}
 
-HUEY = {
-    'backend': 'huey.backends.redis_backend',
-    'name': 'task_queue',
-    'connection': {'host': REDIS_QUEUE["host"], 'port': REDIS_QUEUE["port"], 'db': REDIS_QUEUE["db"]},
-    'always_eager': False,  # Defaults to False when running via manage.py run_huey
-    # Options to pass into the consumer when running ``manage.py run_huey``
-    'consumer_options': {'workers': 50},
-}
 
 SMTP_CONFIG = {"smtp_server": "smtp.mxhichina.com",
                "email": "noreply@qduoj.com",