Re: [PATCH] pgarchives: Fix crash when receiving a request with an incorrect If-Modified-Since header

On Fri, 12 Jun 2026 at 10:52, Célestin Matte <celestin(dot)matte(at)cmatte(dot)me>
wrote:

> Django crashes when receiving a request containing a If-Modified-Since
> header with an incorrect date:
>
>
> Traceback (most recent call last):
> File
> "/path/lib/python3.13/site-packages/django/core/handlers/exception.py",
> line 55, in inner
> response = get_response(request)
> ^^^^^^^^^^^^^^^^^^^^^
> File
> "/path/lib/python3.13/site-packages/django/core/handlers/base.py", line
> 197, in _get_response
> response = wrapped_callback(request, *callback_args,
> **callback_kwargs)
>
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> File "/path/archives/mailarchives/views.py", line 112, in __cache
> resp = fn(request, *_args, **_kwargs)
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> File "/path/archives/mailarchives/views.py", line 500, in message
> if ims >= newest:
> ^^^^^^^^^^^^^
>
> Exception Type: TypeError at /message-id/<redacted>
> Exception Value: '>=' not supported between instances of 'NoneType' and
> 'int'
>
>
> This patch adds a condition to avoid this.
>

Good catch. Applied. Thanks!

>
> (For some reason, archives on postgresql.org do NOT crash on this. Are
> headers filtered before reaching pgarchives there? When deploying upstream
> version of pgarchives locally, I do have this crash)
>

IMS in particular is handled by the cache. So the brwoser does IMS <-> the
cache, and then varnish does it independently <-> backend. And Varnish will
always create the correct headers. And since headers from the client are
never passed through to the backend, it doesn't show up there.

--
Magnus Hagander
Me: https://www.hagander.net/ <http://www.hagander.net/>
Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>