Set progress no update #2901
Set progress no update #2901
Conversation
| @@ -36,7 +36,9 @@ | |||
| ) | |||
| def on_bg_progress(set_progress, _): | |||
| set_progress("start") | |||
| time.sleep(2) | |||
| time.sleep(1) | |||
There was a problem hiding this comment.
Might be better to change this to lock to make sure it's not reset.
There was a problem hiding this comment.
I'm assuming you meant to write look instead of lock. Would 7437e2b work?
The final results for this test (tests/integration/long_callback/test_basic_long_callback014.py) would be:
- Using
dev
- Using this PR
In dev, the #progress-counter is 3 because the value gets incremented every time set_progress is called, but it's correctly being left as 2 with this PR's changes.
As for why #progress-output is set back to start in dev, I am not sure 🤔. However, it's correctly being left as stop in this PR.
There was a problem hiding this comment.
I think @T4rk1n was referring to multiprocessing.Lock, which you can find in some of the other Dash tests. This can remove the need for any explicit sleep statements, which not only makes the tests faster but also more robust on CI where you never know what else is running on the same hardware and can lead to unexpected delays that will intermittently break tests based on sleep.
There was a problem hiding this comment.
Yes, I was talking about a multiprocessing.Lock.
Basically you would do in the callback
with lock:
set_progress(no_update)
Then in the test you can also request the lock and do the assertions, so you can be sure the call to set_progress is done before the assertions.
There was a problem hiding this comment.
Ohh I see, that makes sense. I added the lock in 21bc4b2 🔒
Fixes #2846.
While I wasn't able to replicate the error from the issue, I did find that
set_progress((no_update, str(total)))sets the progress to 0:This is because the progress bar's value is being set to
"[object Object]", which is probably being interpreted as 0. The progress bar's HTML being:<progress id="progress_bar" value="[object Object]" max="5" style="visibility: visible;"></progress>.I modified it so that if
set_progresshasno_updatefor a component's output, that component will not be updated, but the other components—assuming they are notno_update—will be updated.Contributor Checklist
optionals
CHANGELOG.md