[Django] #36293: Add test to verify non-blocking behavior of compress_sequence() with zfile.flush()

[Django]

#36293: Add test to verify non-blocking behavior of compress_sequence() with
zfile.flush()
-------------------------------+-----------------------------------------
Reporter: huoyinghui | Type: Uncategorized
Status: new | Component: Uncategorized
Version: 5.2 | Severity: Normal
Keywords: gzip blocking | Triage Stage: Unreviewed
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+-----------------------------------------
This ticket proposes adding a test to confirm that `compress_sequence()`
in `django.utils.text` correctly flushes each chunk during gzip streaming.

The absence of `zfile.flush()` would cause compressed output to be
buffered,
delaying response delivery in streaming contexts. This test uses timed
chunk generation to verify that data is emitted approximately once per
second,
indicating that gzip output is non-blocking when `flush()` is used.

See related PR: https://github.com/django/django/pull/XXXXX
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Ticket URL: <https://code.djangoproject.com/ticket/36293>
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[Django]

#36293: Add test to verify non-blocking behavior of compress_sequence() with
zfile.flush()
-------------------------------+--------------------------------------

Reporter: huoyinghui | Owner: (none)

Type: Uncategorized | Status: new
Component: Uncategorized | Version: 5.2

Severity: Normal | Resolution:

Keywords: gzip blocking | Triage Stage: Unreviewed
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------------------------

Comment (by huoyinghui):

https://github.com/django/django/pull/19335
--
Ticket URL: <https://code.djangoproject.com/ticket/36293#comment:1>

[Django]

#36293: Add test to verify non-blocking behavior of compress_sequence() with
zfile.flush()
-------------------------------+--------------------------------------
Reporter: huoyinghui | Owner: (none)
Type: Uncategorized | Status: new
Component: Uncategorized | Version: 5.2
Severity: Normal | Resolution:
Keywords: gzip blocking | Triage Stage: Unreviewed
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------------------------

Description changed by huoyinghui:

Old description:

> This ticket proposes adding a test to confirm that `compress_sequence()`
> in `django.utils.text` correctly flushes each chunk during gzip
> streaming.
>
> The absence of `zfile.flush()` would cause compressed output to be
> buffered,
> delaying response delivery in streaming contexts. This test uses timed
> chunk generation to verify that data is emitted approximately once per
> second,
> indicating that gzip output is non-blocking when `flush()` is used.
>
> See related PR: https://github.com/django/django/pull/XXXXX

New description:

This ticket proposes adding a test to confirm that `compress_sequence()`
in `django.utils.text` correctly flushes each chunk during gzip streaming.

The absence of `zfile.flush()` would cause compressed output to be
buffered,
delaying response delivery in streaming contexts. This test uses timed
chunk generation to verify that data is emitted approximately once per
second,
indicating that gzip output is non-blocking when `flush()` is used.

See related PR: https://github.com/django/django/pull/19335

--
--
Ticket URL: <https://code.djangoproject.com/ticket/36293#comment:2>

[Django]

#36293: Add test to verify non-blocking behavior of compress_sequence() with
zfile.flush()
-------------------------------+--------------------------------------
Reporter: huoyinghui | Owner: (none)

Type: New feature | Status: closed
Component: HTTP handling | Version: dev
Severity: Normal | Resolution: needsinfo
Keywords: gzip flush | Triage Stage: Unreviewed

Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------------------------

Changes (by Natalia Bidart):

* cc: Carlton Gibson, Matthew Somerville (added)
* component: Uncategorized => HTTP handling
* keywords: gzip blocking => gzip flush
* resolution: => needsinfo
* status: new => closed
* type: Uncategorized => New feature
* version: 5.2 => dev

Comment:

Hello huoyinghui, thank you for taking the time to create this ticket.
Initially your request made sense, but I did some archeology and in fact
`zfile.flush()` was removed in caa3562d5bec1196502352a715a539bdb0f73c2d
(while fixing #24242). I can see in your patch how you added a flag to
control whether the flushing occurs or not, but I'm not convinced this is
the right solution.

We would need some stronger evidence that the lack of flushing is causing
any issues with a streamed response. The commit above mentions:

> Testing shows without the flush() the buffer is being flushed every 17k
or so and compresses the same as if it had been done as a whole string.

I'll close as `needsinfo`, I'll add as cc a few folks, and edit the ticket
title to be more precise. Please reopen when you can provide more evidence
via a Django test project for proper assestment. Thank you!
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Ticket URL: <https://code.djangoproject.com/ticket/36293#comment:3>