Add Last-Modified header to feeds

[Julian Bez]

The patch adds a Last-Modified header to feeds generated by the syndication app.

We already have the latest date, so why not use it?

Works best with django.middleware.http.ConditionalGetMiddleware, which does the work of responding with 304 etc.

[James Bennett]

This is a minor feature and can safely be dealt with post-1.0.

[(none)]

Milestone post-1.0 deleted

[Julian Bez]

Would be nice to know when post-1.0 is.

[James Bennett]

This is a feature request, and so it cannot go on the 1.2 milestone; 1.2 is feature frozen.

[Julian Bez]

Patch updated against 1.2.1

[Matthias Kestenholz]

Tests are missing.

[Aymeric Augustin]

Patch no longer applies.

[Roman Gladkov]

​https://github.com/django/django/pull/409

[Claude Paroz <claude@…>]

In 08d675a98f1ae1d27f7e1946125ed5316c576802:

Fixed #7936 -- Added Last-Modified header to feeds

Thanks julianb for the report and the initial patch, and Roman
Gladkov for working on tests.

[Markus Holtermann]

Hi, There is another ticket requesting to back-port this feature to 1.4 (or even 1.3). Closed that one as duplicate #20087.

[Ramiro Morales <cramm0@…>]

In 62dfd79f8b4a1f7e702809cc21ce262f19da0f5b:

Fixed #21165 -- Fix test for syndication feed timestamp field on Windows.

Thanks Michael Manfre for the report, Raphaël Barrois for the patch and
Claude Paroz, Aymeric Augustin for the reviews.

Refs #7936.

[Ramiro Morales <ramiro@…>]

In 5252885494079cf28a337644a87e61b19340f09c:

[1.6.x] Fixed #21165 -- Fix test for syndication feed timestamp field on Windows.

Thanks Michael Manfre for the report, Raphaël Barrois for the patch and
Claude Paroz, Aymeric Augustin for the reviews.

Refs #7936

62dfd79f8b from master.