AttributeError: 'function' object has no attribute '__func__' when refreshing a page

[ghost]

When running manage.py runserver, if I access twice to a page using the {% render_placeholder %} tag, I get an error. I need to restart the server to fix the problem and if I ask for the page a second time, the error shows up again.

Traceback (most recent call last):
  File "....../lib/python3.4/site-packages/django/contrib/staticfiles/handlers.py", line 63, in __call__
    return self.application(environ, start_response)
  File "....../lib/python3.4/site-packages/django/core/handlers/wsgi.py", line 189, in __call__
    response = self.get_response(request)
  File "....../lib/python3.4/site-packages/django/core/handlers/base.py", line 218, in get_response
    response = self.handle_uncaught_exception(request, resolver, sys.exc_info())
  File "....../lib/python3.4/site-packages/django/core/handlers/base.py", line 261, in handle_uncaught_exception
    return debug.technical_500_response(request, *exc_info)
  File "....../lib/python3.4/site-packages/django_extensions/management/technical_response.py", line 5, in null_technical_500_response
    six.reraise(exc_type, exc_value, tb)
  File "....../lib/python3.4/site-packages/six.py", line 659, in reraise
    raise value
  File "....../lib/python3.4/site-packages/django/core/handlers/base.py", line 164, in get_response
    response = response.render()
  File "....../lib/python3.4/site-packages/django/template/response.py", line 158, in render
    self.content = self.rendered_content
  File "....../lib/python3.4/site-packages/django/template/response.py", line 135, in rendered_content
    content = template.render(context, self._request)
  File "....../lib/python3.4/site-packages/django/template/backends/django.py", line 74, in render
    return self.template.render(context)
  File "....../lib/python3.4/site-packages/django/template/base.py", line 209, in render
    return self._render(context)
  File "....../lib/python3.4/site-packages/django/test/utils.py", line 96, in instrumented_test_render
    return self.nodelist.render(context)
  File "....../lib/python3.4/site-packages/django/template/base.py", line 903, in render
    bit = self.render_node(node, context)
  File "....../lib/python3.4/site-packages/django/template/debug.py", line 79, in render_node
    return node.render(context)
  File "....../lib/python3.4/site-packages/django/template/loader_tags.py", line 135, in render
    return compiled_parent._render(context)
  File "....../lib/python3.4/site-packages/django/test/utils.py", line 96, in instrumented_test_render
    return self.nodelist.render(context)
  File "....../lib/python3.4/site-packages/django/template/base.py", line 903, in render
    bit = self.render_node(node, context)
  File "....../lib/python3.4/site-packages/django/template/debug.py", line 79, in render_node
    return node.render(context)
  File "....../lib/python3.4/site-packages/django/template/loader_tags.py", line 135, in render
    return compiled_parent._render(context)
  File "....../lib/python3.4/site-packages/django/test/utils.py", line 96, in instrumented_test_render
    return self.nodelist.render(context)
  File "....../lib/python3.4/site-packages/django/template/base.py", line 903, in render
    bit = self.render_node(node, context)
  File "....../lib/python3.4/site-packages/django/template/debug.py", line 79, in render_node
    return node.render(context)
  File "....../lib/python3.4/site-packages/django/template/loader_tags.py", line 65, in render
    result = block.nodelist.render(context)
  File "....../lib/python3.4/site-packages/django/template/base.py", line 903, in render
    bit = self.render_node(node, context)
  File "....../lib/python3.4/site-packages/django/template/debug.py", line 79, in render_node
    return node.render(context)
  File "....../lib/python3.4/site-packages/tag_parser/basetags.py", line 110, in render
    return self.render_tag(context, *tag_args, **tag_kwargs)
  File "....../lib/python3.4/site-packages/tag_parser/basetags.py", line 311, in render_tag
    return self.get_value(context, *tag_args, **tag_kwargs)
  File "....../lib/python3.4/site-packages/fluent_contents/templatetags/fluent_contents_tags.py", line 290, in get_value
    fallback_language=fallback_language
  File "....../lib/python3.4/site-packages/fluent_contents/rendering.py", line 141, in render_placeholder
    output = _render_items(request, placeholder, items, parent_object=parent_object, template_name=template_name, cachable=cachable)
  File "....../lib/python3.4/site-packages/fluent_contents/rendering.py", line 267, in _render_items
    if _is_template_updated(request, contentitem, cachekey):
  File "....../lib/python3.4/site-packages/fluent_contents/rendering.py", line 446, in _is_template_updated
    if plugin.get_render_template.__func__ is not ContentPlugin.get_render_template.__func__:
AttributeError: 'function' object has no attribute '__func__'

Some informations from the Werkzeug command-line :

>>> plugin.__class__
<class 'fluent_contents.plugins.text.content_plugins.TextPlugin'>
>>> hasattr(plugin.get_render_template, '__func__')
True
>>> hasattr(ContentPlugin.get_render_template, '__func__')
False

[vdboor]

Thanks for reporting this! This seems to be a Python 3.4 specific issue, in 3.3 everything still works.
I've fixed this in 9103ad7 You can use that git-release directly before 1.0.2 is released

[vdboor]

Note, you can also use FLUENT_CONTENTS_CACHE_OUTPUT = False in your local settings to workaround this issue. That avoids the _is_template_updated() test, which is only done for development. In production, this doesn't occur either, because it only happens with DEBUG = True.

[ghost]

Thanks, it works ! I put FLUENT_CONTENTS_CACHE_OUTPUT = not DEBUG in my settings just in case.

[vdboor]

Great, glad to hear!

If you have any plugins with dynamic output (e.g. forms) that differ per request, make sure you test them when you enable FLUENT_CONTENTS_CACHE_OUTPUT. These plugins need special attention.