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Celery

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Reference:docs.celeryproject.org

Install ​

shell
sudo apt install rabbitmq-server
pip install celery

Create the task method ​

python
## tasks.py
from celery import Celery

app = Celery('tasks', broker='pyamqp://guest@localhost//')

@app.task
def add(x, y):
    return x + y

Run Celery worker server ​

shell
celery -A tasks worker --loglevel=info

Calling the task ​

python
>>> from tasks import add
>>> add.delay(2, 3)  # Returns AsyncResult

Task status ​

python
from celery.result import AsyncResult
task = AsyncResult("task-id")
task.ready()  # True or False

Raise SoftTimeLimitExceeded exception on the task ​

python
task.revoke(terminate=True, signal='SIGUSR1')

Abortable task ​

python
from celery.contrib.abortable import AbortableTask, AbortableAsyncResult

@app.task(bind=True, base=AbortableTask)
def long_running_task(self):
    # ...
    if self.is_aborted():
        # respect aborted state, and terminate gracefully.
        logger.warning('Task aborted')
        return
    # ...

def cancel_task(task_id):
    task = AbortableAsyncResult(task_id)
    task.abort()