GitHub Gist: instantly share code, notes, and snippets. Losing task methods in 3.2 would cause me to rewrite my entire application. It makes a group of tasks so that I can time how long executing the tasks took, and perform something when they're all done (this is the purpose of res.join  and grouped_subs) The tasks that are grouped are pairs of chained tasks. A chain is a bunch of tasks linked together, when you do `resp = c.delay()` you are queuing all the tasks in the chain The object that `c.delay()` returns is not a pointer to the entire chain but a pointer to the last task int he chain. And that's true for us too. Default is the value of the result_backend setting. I have a check_orders task that's executed periodically. celery,solaris,eventlet. Interestingly enough, calling s = (a.add.s(1,1) | a.show.s(self=a) ).delay().get() spits back the following error: TypeError: s() got multiple values for keyword argument 'self'. Fix the issue and everybody wins. Use case description: Extend Celery so that each task logs its standard output and errors to files. When I try the things I have commented out after  (raising exceptions, removing callbacks)... we get stuck on the join() in check_orders for some reason (it breaks the group). I think you can consider it a failed experiment :(, That is a bummer. So when a subpart of the Chord failed, you can manage the Exception and do what you want with it (log something, requeue a task for alter execution, etc). We’ll occasionally send you account related emails. Mocking the Celery chain and the chained tasks is an easy and effective way to stay on top of your Celery workflow, however complex. celery.accumulate celery-worker_1 | . My celery experience so far has been quite awful to say the least. instruct Celery to do something (or nothing) with a failed task. GitHub Gist: instantly share code, notes, and snippets. If there is a task in between, or just a single group, it works as expected. Celery is not ready at the moment. Unlike the other users who can't seem to start celery regardless if they follow the documentation. Django, ImportError: cannot import name Celery, possible circular , Adding the following lines to cloud/celery.py: import celery print celery.__file__. To use it we can create a new task that just delays them: from celery import shared_task, chain @shared_task def fetch_data_and_store_it(): t1 = fetch_data.s() t2 = store_data.s() return chain(t1, t2).delay() Data returned from the first task will be given to the second one as we use signatures (.s()). To handle exceptions or not? celery.accumulate celery-worker_1 | . Reacting on calls to Celery tasks is one of the first things that you will want to dig deeper in as soon as you start scratching the surface of Celery. Edited to work with EAGER mode, as suggested by @PhilipGarnero in the comments. Task methods will no longer be supported in 3.2. Celery provides Python applications with great control over what it does internally. The following are 30 code examples for showing how to use celery.chain(). 58,547 developers are working on 6,064 open source repos using CodeTriage. It makes a group of tasks so that I can time how long executing the tasks took, and perform something when they're all done (this is the purpose of res.join  and grouped_subs) The tasks that are grouped are pairs of chained tasks. Return type. For example, background computation of expensive queries. Again, the source code for this tutorial can be found on GitHub. In this blog post you will learn how to: handle Celery task errors and automatically retry failed tasks .