Nevow accesses static resources by filename (as opposed to by an open stream), which causes problems for packaging tools such as py2app

[Zooko Wilcox-O'Hearn]

Nevow loads resources by invoking "resource_filename", e.g. http://bazaar.launchpad.net/~divmod-dev/divmod.org/trunk/annotate/head:/Nevow/formless/webform.py#L26 . Packaging tools like py2exe and py2app can easily provide named resources through the "resource_string" or "resource_stream" APIs (http://pythonhosted.org/distribute/pkg_resources.html#resourcemanager-api), but it is more complicated to provide a resource through the "resource_filename" API, and it typically results in failures like this:

  File "allmydata/__init__.pyc", line 265, in <module>
  File "allmydata/__init__.pyc", line 180, in get_package_versions_and_locations
  File "nevow/__init__.pyc", line 143, in <module>
  File "nevow/__init__.pyc", line 29, in load
  File "nevow/util.pyc", line 183, in _namedAnyWithBuiltinTranslation
  File "twisted/python/reflect.pyc", line 464, in namedAny
  File "twisted/python/reflect.pyc", line 400, in _importAndCheckStack
  File "formless/webform.pyc", line 26, in <module>
  File "build/bdist.macosx-10.6-intel/egg/pkg_resources.py", line 884, in resource_filename
  File "build/bdist.macosx-10.6-intel/egg/pkg_resources.py", line 1516, in get_resource_filename
NotImplementedError: resource_filename() only supported for .egg, not .zip

(Copied from this bug report: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/182#comment:34 .)

One way to fix this bug would be to change Nevow to never need filenames for static resources and instead to make do with streams for static resources.