Make syndication's lastBuildDate timezone aware

[didrix]

The lastBuildDate element in an RSS feed is not timezone aware. For instance on a non-utc timezone ('Europe/Amsterdam') it will generate a response with

<lastBuildDate>Mon, 23 May 2016 11:36:39 -0000</lastBuildDate>

while it should be

<lastBuildDate>Mon, 23 May 2016 11:36:39 +0200</lastBuildDate>

relevant files:
django/utils/feedgenerator.py

Seen in version 1.9.6 and 1.10a1, probably more versions affected.
pytz._version_ = 2016.4

[Tim Graham]

I guess a patch might look like:

django/utils/feedgenerator.py

@@ -26 +26 @@
 import datetime
 import warnings
 
-from django.utils import datetime_safe, six
+from django.utils import datetime_safe, six, timezone
 from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.encoding import force_text, iri_to_uri
 from django.utils.six import StringIO
@@ -223 +223 @@
                     if latest_date is None or item_date > latest_date:
                         latest_date = item_date
 
-        return latest_date or datetime.datetime.now()
+        return latest_date or timezone.now()
 
 
 class Enclosure(object):

[didrix]

Replying to timgraham:

I guess a patch might look like:

django/utils/feedgenerator.py

@@ -226 @@
-        return latest_date or datetime.datetime.now()
+        return latest_date or timezone.now()

Could also do this:

django/utils/feedgenerator.py

@@ -226 @@
-        return latest_date or datetime.datetime.now()
+        return latest_date or timezone.localtime(timezone.now())

What do you reckon?

[Aymeric Augustin]

Let's use UTC.

[Ketan Bhatt]

Hey,

This is the first time I am contributing to Django, so please help me if I do some mistakes.

I followed the steps from this guideline ​https://docs.djangoproject.com/en/1.9/internals/contributing/writing-code/working-with-git/

Here is the link to the branch I have done my changes on: ​https://github.com/ketanbhatt/django/tree/ticket_26653

And here is a diff of the master and my branch: ​https://github.com/django/django/compare/master...ketanbhatt:ticket_26653?expand=1

Please take a look and let me know the next steps.

Thank you

[Berker Peksag]

​PR #6648 looks good to me.

[Tim Graham <timograham@…>]

In f31fbba:

Fixed #26653 -- Made SyndicationFeed.latest_post_date() return time in UTC.

[Tim Graham <timograham@…>]

In 37aec6b1:

Refs #26653 -- Fixed a feedgenerator test that requires a database query on PostgreSQL.