matrix-org / matrix-org/matrix-python-sdk

429 responses w/o retry_after_ms cause exception

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#193 4 comments 0 reactions 0 assignees View on GitHub

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bug upstream
Dominant language
Python
Stars
266
Forks
118
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No merged PRs in 30d

Description

Sometimes (no idea how this is triggered) synapse sends responses with a 429 status code without the `retry_after_ms` field. In those cases, the python client crashes with a `KeyError` since https://github.com/matrix-org/matrix-python-sdk/blob/401439f020ba79197c719a9b2d51838d833b731e/matrix_client/api.py#L666 unconditionally expects `retry_after_ms` to be available on 429 responses.

A relatively simple solution would be to have our own internal exponential backoff counter that gets reset every time a request succeeds or an explicit `retry_after_ms` value is received.

What do you think?

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Research direction

Start at matrix_client/api.py around line 666 and inspect the 429 response handling. Done means a 429 response without retry_after_ms no longer raises KeyError, while the existing explicit retry_after_ms behavior and the proposed backoff behavior are addressed.

Written by the indexing model from the issue text.

Assessment

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

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