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errors not reported in new async code

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#1,279 0 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
jupyter, python
Domain
backend

Research direction

Start by locating the ipykernel async launch sites that use start_soon and inspect how their exceptions are handled. The work is done when unhandled exceptions from these launches are caught and logged instead of disappearing into the captured stderr stream.

Written by the indexing model from the issue text.

Description

bug

If errors are raised in the new async code, as I'm seeing in trying to update IPython Parallel to the new async APIs, there is often no indication of a problem, messages just don't get handled.

We need to be careful to catch and log all errors in ipykernel code, because the default excepthook sends them to the captured stderr stream, which won't be seen in the kernel logs. That means everything we launch with e.g. start_soon etc. must be hooked up to a generic try/except to catch and log all unhandled exceptions instead of letting them raise.

Dominant language
Python
Stars
734
Forks
411
Avg merge
1d 2h
Merged PRs (30d)
9

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