Callbacks and Errbacks¶
All tasks accept a
url_errback argument, that allows
to specify a HTTP endpoint that will be called when the task is complete.
This alleviates the need to poll
POST /v2/status to check if a task was
completed and simplifies asynchronous code if you need to queue many tasks at
The callback endpoint will receive a POST containing the full task status as
soon as the task ends (the same JSON that you would get on
POST /v2/status). Note that the request is not form-encoded, the POST
request body contains directly the status in JSON.
If you poll
POST /v2/status just after receiving the callback, it
will most likely return an “executing” status. This is expected, because it
takes some time for the status to propagate to the database. This is also
unneeded, since the final status is contained in the callback request body.