[ckan-dev] pylons/webob issue

Fri Jul 8 13:29:16 UTC 2011

On Fri, Jul 8, 2011 at 1:22 PM, David Read <david.read at okfn.org> wrote:
> This question is for James really with his Pylons knowledge, but I'd
> appreciate thoughts from others with experience in the wider open
> source world.
>
> The latest version of WebOb seems to be incompatible with Pylons
> 0.9.7. It's just a minor thing but it has broken buildbot - pylons
> 0.9.7 imports the class Multidict from webob and Multidict has moved
> to webob.multidict.

It seems that MutiDict was removed from webob in WebOb 0.9.7, with
isn't so recent.

> For a while there has been an import of Multidict
> into webob itself as well to cope with pylons 0.9.7, but this has just
> been removed.

Do you know where in the Pylons 0.9.7 code MultDict is imported from
webob? I can't find it.

Pylons 0.9.7 does import UnicodeMultiDict from webob though, in
decorators / __init__.py. The latest WebOb release, namely WebOb
1.0.8, does have UnicodeMultiDict in the webob namespace. So Pylons
does work with WebOb 1.0.8.

But it seems that things will change in WebOb 1.1. WebOb 1.1beta1 does
indeed not have UnicodeMultiDict in webob. Is it what you're talking
about?

>
> What's the best way to solve this in the short term? Options:
>
> 1) Ask the WebOb maintainer to put back the extra import of MultiDict
> into webob and continue support of Pylons 0.9.7
> 2) Fork Pylons 0.9.7 and force it to use the old version of WebOb
> 3) Fork Pylons 0.9.7 and fix the import of Multidict from WebOb
> 4) Upgrade to Pylons 1.0 (a fair number of small changes required)
>
> Background:
> WebOb has a new maintainer Sergey Schetinin and has been releasing new
> versions in the past couple of weeks that have been changing behaviour
> subtley and caused a couple of buildbot failures in the past week
> already. Today he pushed out version 1.1beta1, which buildbot uses
> straight away because Pylons specifies in its setup.py "Web>=0.9.6.1".

As a short term solution can't you just have WebOb<=1.0.8 in the
requirements of CKAN?

Cheers,

-- 
Eric