Stop Celery caching Django template - django

I have Django 3.24, celery 4.4.7 and celerybeat 2.2.0 setup via the RabbitMQ broker.
I have have a celery task that renders a Django template and then sends it to a number of email recipients.
The Django template is dynamic in as much as changes can be made to it's content at any time, which in turn rewrites the template. The trouble is that on occasions, I have to restart celery to get it to re-read the template.
My question is, is there any way of forcing celery to reread the template file, without requiring a full celery restart?
celery.py
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'backoffice.settings')
app = Celery('backoffice')
default_config = 'backoffice.celery_config'
app.config_from_object(default_config)
app.autodiscover_tasks()
#app.task(bind=True)
def debug_task(self):
print('Request: {0!r}'.format(self.request))
celery_config.py
from django.conf import settings
broker_url = "amqp://someusername:somepassword#webserver:5672/backoffice"
worker_send_task_event = False
task_ignore_result = True
task_time_limit = 60
task_soft_time_limit = 50
task_acks_late = True
worker_prefetch_multiplier = 10
worker_cancel_long_running_tasks_on_connection_loss = True
celery command
celery -A backoffice worker -B -l info --without-heartbeat --without-gossip --without-mingle

Related

Celery beat sends scheduled task only once and then doesn't send task when restarted

I am using Celery beat to perform a task that is supposed to be executed at on specific time. I was trying to excute it now by changing the time just to see if it works correctly. What I have noticed is it sends the task correctly when I run a fresh command that is celery -A jgs beat -l INFO but then suppose I change the time in the schedule section from two minutes or three minutes from now and then again run the above command, beat does not send the task. Then I noticed something strange. If I go to the admin area and delete all the other old tasks that were created in the crontab table, and then run the command again it sends the task again to the worker.
The tasks are being traced by the worker correctly and also the celery worker is working correctly. Below are the codes that I wrote to perform the task.
celery.py
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
from django.conf import settings
from celery.schedules import crontab
from django.utils import timezone
from datetime import timezone
# Set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'jgs.settings')
app = Celery('jgs')
# Using a string here means the worker doesn't have to serialize
# the configuration object to child processes.
# - namespace='CELERY' means all celery-related configuration keys
# should have a `CELERY_` prefix.
app.conf.enable_utc = False
app.conf.update(timezone = 'Asia/Kolkata')
# app.conf.update(BROKER_URL=os.environ['REDIS_URL'],
# CELERY_RESULT_BACKEND=os.environ['REDIS_URL'])
app.config_from_object('django.conf:settings', namespace='CELERY')
# Celery beat settings
app.conf.beat_schedule = {
'send-expiry-email-everyday': {
'task': 'control.tasks.send_expiry_mail',
'schedule': crontab(hour=1, minute=5),
}
}
# Load task modules from all registered Django apps.
app.autodiscover_tasks()
#app.task(bind=True)
def debug_task(self):
print(f'Request: {self.request!r}')
control/tasks.py
from celery import shared_task
from django.core.mail import message, send_mail, EmailMessage
from django.conf import settings
from django.template.loader import render_to_string
from datetime import datetime, timedelta
from account.models import CustomUser
from home.models import Contract
#shared_task
def send_expiry_mail():
template = render_to_string('expiry_email.html')
email = EmailMessage(
'Registration Successfull', #subject
template, # body
settings.EMAIL_HOST_USER,
['emaiid#gmail.com'], # sender email
)
email.fail_silently = False
email.content_subtype = 'html' # WITHOUT THIS THE HTML WILL GET RENDERED AS PLAIN TEXT
email.send()
return "Done"
settings.py
############# CELERY SETTINGS #######################
CELERY_BROKER_URL = 'redis://127.0.0.1:6379'
# CELERY_BROKER_URL = os.environ['REDIS_URL']
CELERY_ACCEPT_CONTENT =['application/json']
CELERY_RESULT_SERIALIZER = 'json'
CELERY_TASK_SERIALIZER = 'json'
CELERY_TIMEZONE = 'Asia/Kolkata'
CELERY_RESULT_BACKEND = 'django-db'
# CELERY BEAT CONFIGURATIONS
CELERY_BEAT_SCHEDULER = 'django_celery_beat.schedulers:DatabaseScheduler'
commands that I am using
for worker
celery -A jgs.celery worker --pool=solo -l info
for beat
celery -A jgs beat -l INFO
Please correct me where I going wrong or what I am writing wrong, I completely in beginer phase in this async part.
I am really sorry if my sentences were confusing above.

celery not working in django and just waiting (pending)

i'm trying found how celery is working. i have a project that have about 10 app.now i want use celery .
setting.py:
CELERY_BROKER_URL = 'amqp://rabbitmq:rabbitmq#localhost:5672/rabbitmq_vhost'
CELERY_RESULT_BACKEND = 'redis://localhost'
i created a user in rabbitmq with this info:username: rabbitq and password:rabbitmq . then i create a vhost with name rabbitmq_vhost and add rabbitmq permission to it. all is fine i think because all of error about rabbitmq disappear .
here is my test.py:
from .task import when_task_expiration
def test_celery():
result = when_task_expiration.apply_async((2, 2), countdown=3)
print(result.get())
task.py:
from __future__ import absolute_import, unicode_literals
import logging
from celery import shared_task
from proj.celery import app
#app.task
def when_task_expiration(task, x):
print(task.id, 'task done')
return True
celery.py:
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
# set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'proj.settings')
app = Celery('proj')
# Using a string here means the worker doesn't have to serialize
# the configuration object to child processes.
# - namespace='CELERY' means all celery-related configuration keys
# should have a `CELERY_` prefix.
app.config_from_object('django.conf:settings', namespace='CELERY')
# Load task modules from all registered Django app configs.
app.autodiscover_tasks()
now when i call test_celery() in python shell it's pending.i try to replace #shared_task and #app.task(bind=True) but noting changed.even i try use .delay() instead apply_async((2, 2), countdown=3) and again nothing happend.
i'm trying to use celery to call a function in specific time during this quesation that i ask in past.thank you.
You most likely forgot to run at least one Celery worker process. To do so, execute the following in the shell: celery worker -A proj.celery -c 4 -l DEBUG (here I assumed your Celery application is defined in proj/celery.py as you have Celery('proj') in there)

Running Management command with celery?

I have never used Celery before and am trying to configure it correctly. I am using redis as the broker and hosting on heroku. This is my first time trying to run asynchronous tasks and I'm struggling. I have a Management command that I would like to run periodically.
celery.py
from __future__ import absolute_import, unicode_literals
import os
import celery
from celery import Celery
import django
from django.conf import settings
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'coffee.settings')
app = Celery('coffee')
app.config_from_object('django.conf:settings', namespace = 'CELERY')
app.autodiscover_tasks(lambda: settings.INSTALLED_APPS)
#app.task(bind= True)
def debug_task(self):
print('Request: {0!r}'.format(self.request))
app.conf.beat_schedule = {
'add-every-30-seconds':{
'task': 'inventory.tasks.boarshead',
'schedule' : 30.0,
'args' : ()
},
}
settings.py
CACHES = {
"default": {
"BACKEND": "redis_cache.RedisCache",
"LOCATION": os.environ.get('REDIS_URL'),
}
}
tasks.py
from celery import shared_task
import celery
import time
from django.core import management
#celery.task
def boarshead():
try:
print("in celery module")
"""Boarshead expired sessions by using Django Management Command."""
management.call_command("clearsessions", verbosity=0)
CreateBoarsHeadList.py
return "success"
except:
print(e)
init.py
from __future__ import absolute_import, unicode_literals
from .celery import app as celery_app
procfile
worker: celery worker --app=tasks.inventory.app
On Celery+Rabbit (and REDIS, not used as backend for years) you will need a proc file for the "web" (Django) and one for the worker, did not see listed. Worker / dyno allocation allows use and access to the manage functionality. Here is the procfile from one of my apps:
web: gunicorn SOME_APP.wsgi --log-file -
worker: celery worker -A QUEUE_APP_NAME -l info --without-gossip --without-mingle --without-heartbeat
QUEUE_APP_NAME is the name of a module (app) where I have all my Celery work and code. worker is called via Procfile in the QUEUE_APP_NAME module (dir), similar code to your Celery file. May not solve you, but getting Celery working is a slow battle.

Celery + Django not working at the same time

I have Django 2.0 project that is working fine, its integrated with Celery 4.1.0, I am using jquery to send ajax request to the backend but I just realized its loading endlessly due to some issues with celery.
Celery Settings (celery.py)
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
# set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'converter.settings')
app = Celery('converter', backend='amqp', broker='amqp://guest#localhost//')
# Using a string here means the worker doesn't have to serialize
# the configuration object to child processes.
# - namespace='CELERY' means all celery-related configuration keys
# should have a `CELERY_` prefix.
app.config_from_object('django.conf:settings', namespace='CELERY')
# Load task modules from all registered Django app configs.
app.autodiscover_tasks()
#app.task(bind=True)
def debug_task(self):
print('Request: {0!r}'.format(self.request))
Celery Tasks (tasks.py)
from __future__ import absolute_import, unicode_literals
from celery import shared_task
#shared_task(time_limit=300)
def add(number1, number2):
return number1 + number2
Django View (views.py)
class AddAjaxView(JSONResponseMixin, AjaxResponseMixin, View):
def post_ajax(self, request, *args, **kwargs):
url = request.POST.get('number', '')
task = tasks.convert.delay(url, client_ip)
result = AsyncResult(task.id)
data = {
'result': result.get(),
'is_ready': True,
}
if result.successful():
return self.render_json_response(data, status=200)
When I send ajax request to the Django app it is loading endlessly but when terminate Django server, and I run celery -A demoproject worker --loglevel=info that's when my tasks are running.
Question
How do I automate this so that when I run Django project my celery tasks will work automatically when I send ajax request?
If you are on development environment, you have to run manually celery worker as it does not run automatically on the background, in order to process the jobs in the queue. So if you want to have a flawless workflow, you need both Django default server and celery worker running. As stated in the documentation:
In a production environment you’ll want to run the worker in the background as a daemon - see Daemonization - but for testing and development it is useful to be able to start a worker instance by using the celery worker manage command, much as you’d use Django’s manage.py runserver:
celery -A proj worker -l info
You can read their documentation for daemonization.
http://docs.celeryproject.org/en/latest/userguide/daemonizing.html

Django - Celery with RabbitMQ: task always remains in PENDING

I have to use Celery 4.0.2 with RabbitMQ 3.6.10 to handle an async task. Then, I have followed this tutorial: https://www.codementor.io/uditagarwal/asynchronous-tasks-using-celery-with-django-du1087f5k
However, I have a slight problem with my task because it's impossible to have a result. My task always remains in "PENDING" state.
My question is what i have to do to get a result ?
Thank you in advance for your answer.
Here my code:
Here my __init_.py:
from __future__ import absolute_import, unicode_literals
# This will make sure the app is always imported when
# Django starts so that shared_task will use this app.
from .celery import app as celery_app
__all__ = ['celery_app']
Here a part of my setting.py:
BROKER_URL = 'amqp://guest:guest#localhost//'
CELERY_ACCEPT_CONTENT = ['json']
CELERY_TASK_SERIALIZER = 'json'
CELERY_RESULT_SERIALIZER = 'json'
Here my celery.py:
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
# set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mysite.settings')
app = Celery('mysite',
backend='amqp',
broker='amqp://guest#localhost//')
# Using a string here means the worker don't have to serialize
# the configuration object to child processes.
# - namespace='CELERY' means all celery-related configuration keys
# should have a `CELERY_` prefix.
app.config_from_object('django.conf:settings', namespace='CELERY')
# Load task modules from all registered Django app configs.
app.autodiscover_tasks()
#app.task(bind=True)
def debug_task(self):
print('Request: {0!r}'.format(self.request))
And my tasks.py
# Create your tasks here
from __future__ import absolute_import, unicode_literals
from celery import shared_task
#shared_task
def add(x, y):
test = "ok"
current_task.update_state(state='PROGRESS',
meta={'test': ok})
return x + y
And here my Django Shell:
>>> from blog.tasks import *
>>> job = add.delay(2,3)
>>> job.state
'PENDING'
>>> job.result
>>>
With a picture of my RabbitMQ interface:
You need to start a worker that will process the tasks you add to queue. From your virtualenv run:
celery worker -A blog -l info