Re: [Twisted-Python] Fwd: [Twisted-commits] r11721 - revert r11685

On Sep 19, 2004, at 12:30 PM, wrote:

twisted/web2 has an unacceptable dependency on nevow that will need to be discussed or removed before this subpackage can be added.

First off -- I consider this a rude thing to do, considering I am far from being unreachable. What was the emergency that prompted this removal at midnight on a saturday night? None? Yeah, that's what I thought.

On Sun, 19 Sep 2004 10:07:57 -0400, Itamar Shtull-Trauring wrote:

...

Why is this unacceptable? We depend on pyOpenSSL for TLS support, etc..

The logistical reasons:

There is no release of Nevow.

There is. Although it's old. This is a very good reason for not releasing twisted.web2. Fortunately, since we have decoupled releases now, it doesn't affect anything else.

None of the buildslaves have even an SVN trunk checkout installed, nor have any of them been asked to install one.

True.

Developers weren't told about this new dependency, so they may not have it installed.

twisted-web ml was. I don't expect developers that don't care about twisted web to install Nevow.

This leads to strangely failing tests, making it difficult to tell if outstanding changes that a developer wants to commit are broken.

I assume you mean "Could not import twisted.web2.test.test_web: Traceback: exceptions.ImportError, No module named nevow.". If so, "strangely failing tests" is quite a hyperbole.

The technical reasons:

Nevow imports Twisted. Therefore, Twisted should not import Nevow.

Twisted is the networking framework and the web server framework. It is lower level than the application server and the templating system. The latter should depend on the former, if a dependency exists, not the reverse. _If_ it is desired for Twisted to gain functionality from a Nevow installed, Nevow must be careful to only import certain things from Twisted.

I would much prefer if Nevow gained functionality from Twisted and not the reverse, but if twisted.web/nevow developers desire things to work as they do currently in twisted.web2, at least the above issues need to be addressed. This thread should serve to resolve one of them (hopefully Twisted developers are now aware of the potential dependency ;).

Most of Twisted web2 does not/will not depend on Nevow. Generation of some server-generated pages does/will. Those tests should just be skipped if Nevow isn't installed. That they aren't is an issue, sure. If you want to have any input on these technical matters I suggest participating on the twisted-web mailing list instead of just randomly removing code. Please re-add it. James