Can't run Celery task in Django - I either get "AppRegistryNotReady: Apps aren't loaded yet" or "RuntimeError: populate() isn't reentrant"

Question

我正在尝试在 Django 中使用 Celery 设置一个任务，每天运行 23:00。

app = Celery('App.tasks', broker='redis://localhost')
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "App.settings")

django.setup() <== PROBLEM

@app.on_after_configure.connect
def setup_periodic_tasks(sender, **kwargs):
    sender.add_periodic_task(
        crontab(hour=23),
        calc_average_rating.s(),
    )


@app.task
def calc_average_rating(final_content_id):

问题是，在这个函数中，我有 Rating = apps.get_model(app_label='App', model_name='Rating')，如果我不调用 django.setup()，那么我会得到 django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.。

但是，如果我调用 django.setup()，任务运行没问题，但我无法执行 manage.py runserver，因为我得到 RuntimeError: populate() isn't reentrant。

有什么解决办法吗？

Answer 1

我不确定如何重现您所处的环境，所以这里是我对环境的一些观察，希望它们对您有所帮助

我有一个 Celery() 对象的唯一地方是在一个独立的文件中，保存在“manage.py startproject”生成的包中，

我认为与大多数 Django 用户相比，我布局 Django 应用程序的方式不同寻常，所以要描述它：

# .git/  # top folder is my vcs
# setup.py  # packaging for exampleapp
# env/  # python venv created to this service
# exampleapp/  # package generated from startapp
# exampleapp/tasks.py  # package generated from startapp
# exampleproject/  # folder generated from startproject
# exampleproject/exampleproject/  # package generated by startproject
# exampleproject/exampleproject/settings.py  # generated
# exampleproject/exampleproject/celery.py  # created based on celery docs

# exampleproject/exampleproject/celery.py
import os

from celery import Celery

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'exampleproject.settings')

app = Celery('exampleproject')

app.config_from_object('django.conf:settings', namespace='CELERY')
app.autodiscover_tasks()

@app.task(bind=True)
def debug_task(self):
    print('Request: {self.request!r}'.format(self=self))

if __name__ == '__main__':
    app.start()

然后我开始 celery 作业，如下所示，其中我的 python 虚拟环境文件夹 'env' 是生成的示例项目包

的同级

(
        cd exampleproject
        ../env/bin/python3 -m celery -A exampleproject  worker -l INFO
        # or 
        ../env/bin/python3 -m celery -A exampleproject  beat -l INFO --scheduler django_celery_beat.schedulers:DatabaseScheduler

)
# and for django
./env/bin/python3 exampleproject/manage.py runserver

可能也有兴趣

# exampleapp/tasks.py
from celery import shared_task

@shared_task
def add(x, y):
    return x+y

# exampleproject/exampleproject/settings.py
# suffixed to end of generated file

INSTALLED_APPS.extend([
    'django_celery_results',
    'django_celery_beat',
])

CELERY_TASK_TRACK_STARTED = True
CELERY_TASK_TIME_LIMIT = 30 * 60
CELERY_RESULT_BACKEND = 'django-db'
#CELERY_RESULT_BACKEND = 'django-cache'

对于这些部分，我没有注意到加载入口点有任何问题

Can't run Celery task in Django - I either get "AppRegistryNotReady: Apps aren't loaded yet" or "RuntimeError: populate() isn't reentrant"

Can't run Celery task in Django - I either get "AppRegistryNotReady: Apps aren't loaded yet" or "RuntimeError: populate() isn't reentrant"

django

celery

django-celery