Maintain cleanup context and startup insertion order (#3191)

[Maillol]

What do these changes do?

We can mix app.cleanup_ctx and app.on_startup the order is preserved.

Are there changes in behavior for the user?

When the startup signal is sent, the handlers added to the on_startup list before the cleanup_ctx will
be executed firstly.

Related issue number

#3191

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
• If you provide code modification, please add yourself to CONTRIBUTORS.txt
  • The format is <Name> <Surname>.
  • Please keep alphabetical order, the file is sorted by names.
• Add a new news fragment into the CHANGES folder
  • name it <issue_id>.<type> for example (588.bugfix)
  • if you don't have an issue_id change it to the pr id after creating the pr
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    • .feature: Signifying a new feature.
    • .bugfix: Signifying a bug fix.
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    • .misc: A ticket has been closed, but it is not of interest to users.
  • Make sure to use full sentences with correct case and punctuation, for example: "Fix issue with non-ascii contents in doctest text files."

[Maillol]

I found an other way to have the same behavior, I add callback to on_startup and on_cleanup at each cleanup_ctx.append. The callback added to on_cleanup is enable only if on_startup is executed. I will push a new MR version tomorrow.

[asvetlov]

Please go ahead

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@c8485f6). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #3194   +/-   ##
=========================================
  Coverage          ?   97.97%           
=========================================
  Files             ?       44           
  Lines             ?     8068           
  Branches          ?     1356           
=========================================
  Hits              ?     7905           
  Misses            ?       68           
  Partials          ?       95

Impacted Files	Coverage Δ
aiohttp/web_app.py	95.97% <100%> (ø)

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[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