Error messages should be simplified in some cases

[saper]

One of MediaWiki users reported recently this error (it's here reformatted, since the HTML output is in plain):

An error occured on the render server: 
RuntimeError: 
RuntimeError: command failed with returncode 256: ['mw-zip', 
   '-o', '/home/pp/cache/27/276bad5cc679d168/collection.zip', 
   '-m', '/home/pp/cache/27/276bad5cc679d168/metabook.json', 
   '--status', 'qserve://localhost:14311/276bad5cc679d168:makezip', 
   '--template-blacklist', 'MediaWiki:PDF Template Blacklist', 
   '--template-exclusion-category', 'Exclude in print', 
   '--print-template-prefix', 'Print', 
   '--print-template-pattern', '$1/Print', 
   '--username', 'wikicollect', '--password', '{OMITTED}']
Last Output:
    2012-06-19T21:24:01 mwlib.options.warn >> Both --print-template-pattern and 
          --print-template-prefix (deprecated) specified. Using --print-template-pattern only.
    1%  creating nuwiki in u'/home/pp/cache/27/276bad5cc679d168/tmpbw0czq/nuwiki'
    removing tmpdir u'/home/pp/cache/27/276bad5cc679d168/tmpbw0czq'
    memory used: res=16.4 virt=123.1
    1% error Traceback (most recent call last):
      File "/home/pp/local/bin/mw-zip", line 9, in <module>
        load_entry_point('mwlib==0.13.6', 'console_scripts', 'mw-zip')()
      File "/home/pp/local/lib/python2.7/site-packages/mwlib/apps/buildzip.py", line 155, in main
        make_zip(output, options, env.metabook, podclient=podclient, status=status)
      File "/home/pp/local/lib/python2.7/site-packages/mwlib/apps/buildzip.py", line 50, in make_zip
        make_nuwiki(fsdir, metabook=metabook, options=options, podclient=podclient, status=status)
      File "/home/pp/local/lib/python2.7/site-packages/mwlib/apps/make_nuwiki.py", line 152, in make_nuwiki
        assert x.wikiident in id2wiki, "no wikiconf for %r (%s)" % (x.wikiident,  x)
    AssertionError: no wikiconf for None (<article {'_env': <mwlib.wiki.Environment object at 0x1d8d6d0>, 
           'content_type': u'text/x-wiki', 'title': u'Main Page', 'timestamp': u'1325800496', 'type': 'article', 'revision': u'1'}>)
     in function system, file ./bin/nslave.py, line 63 in function qaddw, file /home/pp/local/lib/python2.7/site-packages/qs/slave.py, line 66

This is basically saying "Could not figure out your MediaWiki URL configuration", as his Short URL setup prevented PediaPress service to access this wiki properly.

This verbose output was helpful to figure out what's wrong, but maybe in some cases a dedicated exception should be delivered.

[ajithhub]

That would be super helpful. I just spent quite some time trying to track down a similar problem. In my case it wasn't the ShortURL config, but the fact that my wiki is at the root of my site.

pediapress/Collection#1