Wsgi content length

[d-maurer]

Allows administrators to fix #1171.

The PR defines the new paste.filter_app_factory entry point content_length corresponding to a WSGI middleware component honoring a Content-Length request header.

Administrators can integrate this middleware into the WSGI pipeline when the used WSGI server does not honor the Content-Length request header. The WSGI spec recommends in note 1 of section Input and Error Streams that servers should honor the Content-Length request header. Therefore, most servers will do and the middleware should rarely be necessary; but there are exceptions, e.g. Python's wsgiref.simple_server.

[icemac]

I like the approach especially the change in the zope.ini skel file documenting the usage.

[dataflake]

Just the one test module name change

[d-maurer]

Michael Howitz wrote at 2023-10-17 23:07 -0700:

@icemac approved this pull request. I like the approach especially the change in the zope.ini skel file documenting the usage. On src/ZPublisher/tests/test_paste.py: The module under test is called `pastefilter`, so I'd prefer the test module to be called `test_pastefilter`.

I have used the more general `test_paste` because initially I wanted to test more of the WSGI related configuration. e.g. `paste.deploy.loadapp` (applied to `Zope2.utilities:skel/zope.ini.in`). As far as I know, there are not yet tests for this. After the recognition that the WSGI middleware already used by `Zope` (--> `httpexceptions`) has no filter definition in `zope.ini` but is included in the pipeline via a direct `egg:` reference, I decided to do the same with the new middleware component. Its test therefore did not require a `zope.ini` reference and I postponed other WSGI configuration tests. Do you think that such tests would be beneficial? Would `ZPublisher` be an appropriate place for such tests? If you answer twice with "yes", I think `test_paste` could be retained as container for future paste/WSGI configuration tests. If you would put such tests elsewhere (they depend on `setup.py` for `egg:` references and potentially `Zope2.utilities:skel` for server, application tests), I agree that `test_paste` should get renamed.