Poll task resturns SUCCESS, but no results

[duncanwilson]

Intermittently, when you poll a submitted task in javascript, when it returns as status: SUCCESS the results are not listed.

This seems to occur most often when the task poll is done immediately after the POST to the celery queue.

However, it has happened other times, such as when I have the poll on a repeated loop if status=PENDING ... then re-poll after a wait period, for example. If I re-poll every 100 ms, then periodically I will see this problem pop up.

[mbstacy]

@duncanwilson I have also noticed this type of behavior. Also, sorry for the delay in responding to this issue. I'm currently planning to update celery application and API code. The API code definitely needs to be updated. The problem is that the task is finishing before the results are stored within the tombstone in the database(mongo). The status of the task "SUCCESS" but tombstone(results) are not available within the database. I really don't want to introduce code that will wait for results. @tdpearson Two options: 1. add code to wait for a second 2. Have frontend poll for results. Thoughts?

[tdpearson]

@mbstacy I would rather wait until the backend is updated to see if it resolves the timing issue than add latency to the whole system right now. As a work around until that happens, polling with error handling on the frontend would be my recommendation.

[jduckles]

Since the beginning I've thought opening a WebSocket might be a better thing than polling here.

[tdpearson]

I am not convinced that websockets is the solution here. However, it would be a great alternative to polling. I have seen Django Channels picking up speed.