Question

I am using reportlab with my Google AppEngine project and I cannot get it to work with the dev_appserver. It runs great in production without any issues. I have placed Reportlab in my project as the entire directory from the 2.5.5 source, I am not using the zip version which previously reported this same issue.

It seems to run fine the first time, but then every subsequent time there seem to be issues. I tried shutting everything down and erasing the pyc files and that doesn’t seem to get the problem to go away, however if I delete the entire Reportlab directory and recopy it from the source then it will work 1 time, and never work again.

I am using the latest SDK(1.6.6) and latest production Reportlab(2.5) with Python 2.7 and NDB. My dev_appserver is running on Mac osX Lion

Here is the traceback I am getting.

Traceback (most recent call last):
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/runtime/wsgi.py", line 187, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/runtime/wsgi.py", line 225, in _LoadHandler
    handler = __import__(path[0])
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1858, in load_module
    return self.FindAndLoadModule(submodule, fullname, search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1722, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1665, in LoadModuleRestricted
    description)
  File "/Users/dramus/gatherthefamily/gtf.py", line 16, in <module>
    from controllers.sharing import SharingPage, BookPage, BookTask
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1858, in load_module
    return self.FindAndLoadModule(submodule, fullname, search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1722, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1665, in LoadModuleRestricted
    description)
  File "/Users/dramus/gatherthefamily/controllers/sharing.py", line 11, in <module>
    from projects.bookmaker import BookMaker
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1858, in load_module
    return self.FindAndLoadModule(submodule, fullname, search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1722, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1665, in LoadModuleRestricted
    description)
  File "/Users/dramus/gatherthefamily/projects/bookmaker.py", line 7, in <module>
    from reportlab.lib.styles import ParagraphStyle as PS
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1858, in load_module
    return self.FindAndLoadModule(submodule, fullname, search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1722, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1665, in LoadModuleRestricted
    description)
  File "/Users/dramus/gatherthefamily/reportlab/lib/styles.py", line 27, in <module>
    from reportlab.rl_config import canvas_basefontname as _baseFontName
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1858, in load_module
    return self.FindAndLoadModule(submodule, fullname, search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1722, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 676, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver_import_hook.py", line 1665, in LoadModuleRestricted
    description)
  File "/Users/dramus/gatherthefamily/reportlab/rl_config.py", line 235, in <module>
    _startUp()
  File "/Users/dramus/gatherthefamily/reportlab/rl_config.py", line 207, in _startUp
    if rl_isdir(d): P.append(d)
  File "/Users/dramus/gatherthefamily/reportlab/lib/utils.py", line 468, in rl_isdir
    return len(filter(lambda x,pn=pn: x.startswith(pn),__loader__._files.keys()))>0
AttributeError: 'HardenedModulesHook' object has no attribute '_files'
INFO     2012-06-14 01:09:54,504 dev_appserver.py:2904] "GET / HTTP/1.1" 500 -

Answer 1

If you look at the reportlab 2.5 code, lib/utils.py lines 463 to 468

def rl_isdir(pn,os_path_isdir=os.path.isdir,os_path_normpath=os.path.normpath):
    if os_path_isdir(pn): return True
    if _isFSD or __loader__ is None: return False
    pn = _startswith_rl(os_path_normpath(pn))
    if not pn.endswith(os.sep): pn += os.sep
    return len(filter(lambda x,pn=pn: x.startswith(pn),__loader__._files.keys()))>0

There seems to be some magic in that utils file, and in this method there are assumptions about internal structure of the loader. The HardenedModulesHook (used for emulating sandbox) does not have a _files attribute, so it fails with the SDK.

As it works in production, rl_isdir might return True or False on any of the lines before the last one, or the __loader__ might look different.

I suggest modifying the utils.py file as it’s included in your application directory anyway, perhaps replace line 468 to just return False.