#176 closed defect (fixed)

missing freeform-default.css -- nevow install error?

Reported by: zooko Owned by: warner
Priority: minor Milestone: eventually
Component: packaging Version: 0.6.1
Keywords: Cc:
Launchpad Bug:


When I click on an html file on win32 (namely my slide-1.html), then I get an unresponsive UI and these kinds of log messages:

2007-10-13 22:43:32.875Z [Uninitialized] Stopping factory <foolscap.negotiate.TubConnectorClientFactory object [from jbzjax2i] [to kzl7rg4a] at 0x0186E650>

2007-10-13 22:43:33.078Z [HTTPChannel,0,] - - [13/Oct/2007:22:43:32 +0000] "GET / HTTP/1.1" 200 2259 "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20070914 Firefox/"

2007-10-13 22:43:33.092Z [HTTPChannel,0,] Unhandled Error

	Traceback (most recent call last):

	  File "c:\Python25\Lib\site-packages\twisted\internet\defer.py", line 191, in addCallback


	  File "c:\Python25\Lib\site-packages\twisted\internet\defer.py", line 182, in addCallbacks


	  File "c:\Python25\Lib\site-packages\twisted\internet\defer.py", line 317, in _runCallbacks

	    self.result = callback(self.result, *args, **kw)

	  File "c:\python25\lib\site-packages\nevow-0.9.18-py2.5.egg\nevow\appserver.py", line 158, in gotPageContext

	    pageContext.tag.renderHTTP, pageContext

	--- <exception caught here> ---

	  File "c:\Python25\Lib\site-packages\twisted\internet\defer.py", line 107, in maybeDeferred

	    result = f(*args, **kw)

	  File "c:\python25\lib\site-packages\nevow-0.9.18-py2.5.egg\nevow\static.py", line 273, in renderHTTP


	  File "c:\Python25\Lib\site-packages\twisted\python\filepath.py", line 383, in restat

	    self.statinfo = stat(self.path)

	exceptions.WindowsError: [Error 2] The system cannot find the file specified: 'c:\\Python25\\lib\\site-packages\\nevow-0.9.18-py2.5.egg\\formless\\freeform-default.css'


2007-10-13 22:43:33.125Z [HTTPChannel,0,] - - [13/Oct/2007:22:43:32 +0000] "GET /webform_css HTTP/1.1" 500 5841 "http://localhost:8123/" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20070914 Firefox/"

Attachments (2)

nevow_setup.patch.txt (4.8 KB) - added by zooko at 2008-01-23T23:10:31Z.
Nevow-0.9.18-setup.patch.txt (5.6 KB) - added by zooko at 2008-01-24T00:12:33Z.

Download all attachments as: .zip

Change History (23)

comment:1 Changed at 2007-10-13T23:10:09Z by warner

hm, is that .css file not getting installed properly? Nevow ought to install that when its 'setup.py install' is run, but maybe the eggstuff is failing?

Weird that this should screw up the UI, though.. I'd have expected it to just report a 404. It's just a little CSS file, and in fact I think we aren't using anything from it.

comment:2 Changed at 2007-10-14T00:56:35Z by zooko

You are right that this doesn't actually screw up the UI.

The UI hung earlier for reasons unknown -- waiting for a storage server, perhaps? I can't reproduce the UI hanging now.

The error messages continues to appear in logs whenever I load a page.

comment:3 Changed at 2007-10-14T00:56:57Z by zooko

  • Summary changed from can't download and display html files on Windows -- nevow install error? to missing freeform-default.css -- nevow install error?

comment:4 Changed at 2007-10-14T00:57:02Z by zooko

  • Owner changed from somebody to zooko
  • Status changed from new to assigned

comment:5 Changed at 2007-10-14T00:59:25Z by zooko

The path that it gets installed to differs from the one it uses to stat the file:

          File "c:\python25\lib\site-packages\nevow-0.9.18-py2.5.egg\nevow\static.py", line 273, in renderHTTP
          File "c:\Python25\Lib\site-packages\twisted\python\filepath.py", line 383, in restat
            self.statinfo = stat(self.path)
        exceptions.WindowsError: [Error 2] The system cannot find the file specified: 'c:\\Python25\\lib\\site-packages\\nevow-0.9.18-py2.5.egg\\formless\\freeform-default.css'

compared to

$ find /c/Python25/ -iname '*freeform-default*'

comment:6 Changed at 2007-10-15T13:50:31Z by zooko

  • Owner changed from zooko to warner
  • Status changed from assigned to new

As far as I can tell, this installation glitch doesn't interfere with Tahoe functionality. Brian: if you think that this is unlikely to cause any actual problems for users (on Windows) in the current version, will you please bump this ticket out of Milestone v0.6.1?

comment:7 Changed at 2007-10-15T20:16:31Z by warner

  • Milestone changed from 0.6.1 to 0.7.0

ok, if the unresponsive UI thing was unrelated, then I'm ok with pushing this out

comment:8 Changed at 2007-10-18T23:29:46Z by zooko

  • Milestone changed from 0.7.0 to 0.6.2
  • Version changed from 0.6.0 to 0.6.1

comment:9 Changed at 2007-10-31T07:41:35Z by warner

I looked at this briefly, it looked like the problem was that the Nevow setup.py was manually assembling the target directory for it's package_data (using something like "/usr/lib/python%s" % sys.version), and the actual install process (setuptools?) was using /usr/lib/python/ (without the version number).

There's a comment in the Nevow setup.py saying "this sucks, we should use pkg_resources instead". Maybe we should write a patch for them? I think they were trying to maintain python2.3 compatibility at one point, though.

comment:10 Changed at 2007-10-31T15:58:28Z by zooko

Does that difference that you've observed also explain the fact that on Windows Nevow was attempting to stat c:\Python25\lib\site-packages\nevow-0.9.18-py2.5.egg\formless\freeform-default.css but the file was in C:\Python25\Lib\site-packages\nevow-0.9.18-py2.5.egg\Lib\site-packages\formless\freeform-default.css ?

The standard distutils behavior on Windows is to use C:\PythonXY\Lib\site-packages and on other systems to use $PREFIX\lib\pythonX.Y\site-packages.

How do we contact the Nevow folks -- through their trac?

comment:11 Changed at 2007-10-31T15:58:36Z by zooko

  • Milestone changed from 0.6.2 to 0.7.0

comment:12 Changed at 2007-10-31T18:42:48Z by warner

I suspect it does, but I didn't take careful notes when I noticed that stuff. I was trying to install nevow on an OS-X box into a non-.egg directory when I saw it, and I think I fixed the problem by patching the nevow setup.py .

And yes, the divmod Trac is probably the most persistent/public way to get them to fix it. The most immediate way would be to hassle them on the #twisted or #twisted-web irc channel, but in general trac tickets are preferred.

comment:13 Changed at 2007-11-01T18:14:55Z by zooko

  • Milestone changed from 0.7.0 to 0.7.1

We're focussing on an imminent v0.7.0 (see the roadmap) which hopefully has #197 -- Small Distributed Mutable Files and also a fix for #199 -- bad SHA-256. So I'm bumping less urgent tickets to v0.7.1.

comment:14 Changed at 2007-11-13T19:40:01Z by zooko

  • Priority changed from major to minor

comment:15 Changed at 2007-11-20T19:59:02Z by zooko

Hm. I did a quick query on the Nevow trac for "pkg_resources", and found these patches which apparently make Nevow use pkg_resources. The weird part is that these patches were apparently committed to Nevow trunk two years ago:

http://divmod.org/trac/changeset/2238 http://divmod.org/trac/changeset/2262 http://divmod.org/trac/changeset/2263

comment:16 Changed at 2008-01-23T02:51:39Z by zooko

  • Milestone changed from 0.7.1 to undecided

comment:17 Changed at 2008-01-23T23:10:04Z by zooko

Okay, the Nevow 0.9.29 release comes with a setup.py} and also with a [http://divmod.org/trac/browser/trunk/Nevow/setup_egg.py setup_egg.py. The latter uses setuptools to decide where to put the package_data so that pkg_resources can later find it. (It is worth comparing those two files visually -- the stanza at the top of nevow's setup.py which starts with "if sys.platform" is the place where that script is deciding where to put these files.

If we use the setuptools version then this bug is fixed -- Nevow can find its data files at runtime. I tested the fix on Cygwin, Windows, and Mac.

The problem is that our packaging policy forbids us to patch 3rd-party libraries that we use, and there isn't a way to automate the use of the setup_egg.py without patching the Nevow tarball (or else writing a script to build Nevow differently from the way we build other dependent libs, which is the moral equivalent of patching the Nevow tarball).

Attached is a patch for Nevow that makes Nevow's setup.py choose whether to use the custom-Nevow setup script or the setuptools setup script at build time, based on whether setuptools can be imported. This patch is not yet tested. I intend to add a unit test (to allmydata.org Tahoe) which fails if Nevow can't find its resources files at run-time, and then to provisionally patch Nevow with this patch. This violates our policy of not patching 3rd-party libraries, but I don't know of a better way to fix this issue.

Changed at 2008-01-23T23:10:31Z by zooko

comment:18 Changed at 2008-01-24T00:12:11Z by zooko

Here's a version of the patch for Nevow-0.9.18, which is the version that we currently use. I also wrote a unit test that simply calls


This incurs an exception -- can't find the default css file -- without the patch and passes with the patch.

Changed at 2008-01-24T00:12:33Z by zooko

comment:19 Changed at 2008-03-04T22:24:35Z by zooko

Submitted a patch to divmod: http://www.divmod.org/trac/ticket/2527

comment:20 Changed at 2008-12-05T23:36:50Z by zooko


Has finally been fixed on Nevow trunk. The next release of Nevow will no longer have this problem. I guess I should wait til then to close this ticket.

comment:21 Changed at 2009-06-30T19:19:44Z by zooko

  • Resolution set to fixed
  • Status changed from new to closed

This is fixed as of Nevow v0.9.33.

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