[Django] #26603: Can't use lazy objects as template names with cached loader anymore
Django
---------------------------------+--------------------
Reporter: sephii | Owner: nobody
Type: Bug | Status: new
Component: Template system | Version: 1.9
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
---------------------------------+--------------------
It looks like commit
https://github.com/django/django/commit/bd145e7209a0e628cced10384bd6f62d65c0f211
introduced a regression in Django 1.9.6. Before this commit, you could
pass a lazy object to the {% extends %} tag and it would work just fine,
however with Django 1.9.6 the following exception is raised:
{{{
Template error:
In template /home/vagrant/ENV/local/lib/python2.7/site-
packages/parler/templates/admin/parler/change_form.html, error at line 1
sequence item 0: expected string, __proxy__ found 1 : {% extends
default_change_form_template|default:"admin/change_form.html" %}
2 :
3 : {% block field_sets %}
4 : {% if language_tabs %}{% include "admin/parler/language_tabs.html"
%}{% endif %}
5 : {{ block.super }}
6 : {% endblock %}
7 :
Traceback:
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/core/handlers/base.py" in get_response
174. response =
self.process_exception_by_middleware(e, request)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/core/handlers/base.py" in get_response
172. response = response.render()
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/response.py" in render
160. self.content = self.rendered_content
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/response.py" in rendered_content
137. content = template.render(context, self._request)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/backends/django.py" in render
95. return self.template.render(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/base.py" in render
206. return self._render(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/test/utils.py" in instrumented_test_render
92. return self.nodelist.render(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/base.py" in render
992. bit = node.render_annotated(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/base.py" in render_annotated
959. return self.render(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/loader_tags.py" in render
151. compiled_parent = self.get_parent(context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/loader_tags.py" in get_parent
148. return self.find_template(parent, context)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/loader_tags.py" in find_template
128. template_name, skip=history,
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/engine.py" in find_template
157. name, template_dirs=dirs, skip=skip,
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/loaders/cached.py" in get_template
49. key = self.cache_key(template_name, template_dirs, skip)
File "/home/vagrant/ENV/local/lib/python2.7/site-
packages/django/template/loaders/cached.py" in cache_key
103. return '-'.join(filter(bool, [template_name, skip_prefix,
dirs_prefix]))
Exception Type: TypeError at
/en/admin/aldryn_newsblog/newsblogconfig/1/change/
Exception Value: sequence item 0: expected string, __proxy__ found
}}}
You can easily reproduce the problem in a new project by using the
following code in the urls.py file:
{{{
#!python
from django.views.generic import TemplateView
from django.utils.functional import lazy
class TestView(TemplateView):
template_name = 'home.html'
def get_context_data(self, **kwargs):
context = super(TestView, self).get_context_data(**kwargs)
context['extended_template'] = lazy(lambda: 'base.html')
return context
urlpatterns = [
url(r'^$', TestView.as_view()),
]
}}}
And create a file templates/home.html (and adapt the template dirs
accordingly):
{{{
{% extends extended_template %}
}}}
The bug is present on master as well.
--
Ticket URL: <https://code.djangoproject.com/ticket/26603>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: assigned
Component: Template system | Version: 1.9
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
Changes (by charettes):
* status: new => assigned
* severity: Normal => Release blocker
* needs_better_patch: => 0
* needs_tests: => 0
* owner: nobody => charettes
* needs_docs: => 0
* stage: Unreviewed => Accepted
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:1>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: assigned
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
Changes (by charettes):
* has_patch: 0 => 1
Comment:
[https://github.com/django/django/pull/6580 PR]
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:2>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: assigned
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by timgraham):
* stage: Accepted => Ready for checkin
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:3>
Django
Reporter: sephii | Owner: charettes
Component: Template system | Version: 1.9
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by Simon Charette <charette.s@…>):
* status: assigned => closed
* resolution: => fixed
Comment:
In [changeset:"207c5b4acd410dd39bac31457dae26a0d15b8b93" 207c5b4]:
{{{
#!CommitTicketReference repository=""
revision="207c5b4acd410dd39bac31457dae26a0d15b8b93"
Fixed #26603 -- Forced lazy template names to text when computing cache
key.
Refs #26536.
Thanks Sylvain Fankhauser for the very detailed report.
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:4>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: closed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Simon Charette <charette.s@…>):
In [changeset:"6a67dce9ccbb2533cbb3fb8d16affdf17dd1f8e7" 6a67dce]:
{{{
#!CommitTicketReference repository=""
revision="6a67dce9ccbb2533cbb3fb8d16affdf17dd1f8e7"
[1.9.x] Fixed #26603 -- Forced lazy template names to text when computing
cache key.
Refs #26536.
Thanks Sylvain Fankhauser for the very detailed report.
Backport of 207c5b4acd410dd39bac31457dae26a0d15b8b93 from master
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:5>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: closed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by vytisb):
The last commit breaks tests in 1.9 because `lazystr` doesn't exist yet.
{{{
======================================================================
ERROR: template_tests.test_loaders (unittest.loader.ModuleImportFailure)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/lib64/python3.4/unittest/case.py", line 58, in
testPartExecutor
yield
File "/usr/lib64/python3.4/unittest/case.py", line 577, in run
testMethod()
File "/usr/lib64/python3.4/unittest/loader.py", line 32, in testFailure
raise exception
ImportError: Failed to import test module: template_tests.test_loaders
Traceback (most recent call last):
File "/usr/lib64/python3.4/unittest/loader.py", line 312, in _find_tests
module = self._get_module_from_name(name)
File "/usr/lib64/python3.4/unittest/loader.py", line 290, in
_get_module_from_name
__import__(name)
File "/home/vytis/src/django/tests/template_tests/test_loaders.py", line
16, in <module>
from django.utils.functional import lazystr
ImportError: cannot import name 'lazystr'
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:6>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: closed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by charettes):
I'll take care of that.
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:7>
Django
Reporter: sephii | Owner: charettes
Type: Bug | Status: closed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Simon Charette <charette.s@…>):
In [changeset:"de22123d3f0eab9495f2f04f972a3bcee7ad1b1c" de22123d]:
{{{
#!CommitTicketReference repository=""
revision="de22123d3f0eab9495f2f04f972a3bcee7ad1b1c"
[1.9.x] Refs #26603 -- Defined lazystr for a template loader test.
Thanks vytisb for the report.
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/26603#comment:8>