Do not hang on 206 Partial Content response with Content-Encoding: gzip

[pauleikis]

What do these changes do?

Do not raise ContentEncodingError('deflate') for gzip encoding when the response is partial. This can be a valid response in case of 206 Partial Content. The bug was not reproducible with deflate or brotli encoding

Are there changes in behavior for the user?

User behaviour is not affected

Related issue number

This fixes #3123

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
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[codecov-io]

Codecov Report

Merging #3124 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #3124   +/-   ##
=======================================
  Coverage   98.09%   98.09%           
=======================================
  Files          43       43           
  Lines        7833     7833           
  Branches     1351     1351           
=======================================
  Hits         7684     7684           
  Misses         57       57           
  Partials       92       92

Impacted Files	Coverage Δ
aiohttp/http_parser.py	98.06% <100%> (ø)	⬆️

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[asvetlov]

Hi.
Thanks for the contribution.
Would you add a test to make sure that the problem is fixed and will not return back by future code modifications?

[pauleikis]

Actually I was trying to reproduce it aiohttp server, but did not manage to send the required response. Luckily I found some in the wild (can be seen in #3123) Not sure how to write the test. If I understand correctly, aiohttp server does not support 206 for non-file responses.

[asvetlov]

You can gzip the body in web handler and return a regular response with the partial body and Content-Encoding header set.

[pauleikis]

OK, will try to cook something up

[pauleikis]

Added tests. Please review again.

[asvetlov]

thanks

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a [new issue] for related bugs.
If you feel like there's important points made in this discussion, please include those exceprts into that [new issue].
[new issue]: https://github.com/aio-libs/aiohttp/issues/new