From 5bc5ddd8b5d787c5e744efead184d46c55d03687 Mon Sep 17 00:00:00 2001 From: Preston Timmons Date: Tue, 3 Feb 2015 15:35:55 -0600 Subject: [PATCH] Fixed #24235 -- Removed is_usable attribute from template loaders. --- django/template/engine.py | 13 +---------- django/template/loaders/app_directories.py | 1 - django/template/loaders/base.py | 1 - django/template/loaders/cached.py | 1 - django/template/loaders/eggs.py | 25 ++++++++++++---------- django/template/loaders/filesystem.py | 2 -- django/template/loaders/locmem.py | 1 - docs/releases/1.9.txt | 10 +++++++++ 8 files changed, 25 insertions(+), 29 deletions(-) diff --git a/django/template/engine.py b/django/template/engine.py index edd731a46c..b346f41f8b 100644 --- a/django/template/engine.py +++ b/django/template/engine.py @@ -121,18 +121,7 @@ class Engine(object): "instead of django.template.loaders.base.Loader. " % loader, RemovedInDjango20Warning, stacklevel=2) - loader_instance = loader_class(*args) - - if not loader_instance.is_usable: - warnings.warn( - "Your template loaders configuration includes %r, but " - "your Python installation doesn't support that type of " - "template loading. Consider removing that line from " - "your settings." % loader) - return None - else: - return loader_instance - + return loader_class(*args) else: raise ImproperlyConfigured( "Invalid value in template loaders configuration: %r" % loader) diff --git a/django/template/loaders/app_directories.py b/django/template/loaders/app_directories.py index 00ca56c84a..17e2183bfc 100644 --- a/django/template/loaders/app_directories.py +++ b/django/template/loaders/app_directories.py @@ -14,7 +14,6 @@ from .base import Loader as BaseLoader class Loader(BaseLoader): - is_usable = True def get_template_sources(self, template_name, template_dirs=None): """ diff --git a/django/template/loaders/base.py b/django/template/loaders/base.py index c7060725c7..66c2986343 100644 --- a/django/template/loaders/base.py +++ b/django/template/loaders/base.py @@ -2,7 +2,6 @@ from django.template.base import Template, TemplateDoesNotExist class Loader(object): - is_usable = False # Only used to raise a deprecation warning. Remove in Django 2.0. _accepts_engine_in_init = True diff --git a/django/template/loaders/cached.py b/django/template/loaders/cached.py index aead14490a..5c53b0a658 100644 --- a/django/template/loaders/cached.py +++ b/django/template/loaders/cached.py @@ -11,7 +11,6 @@ from .base import Loader as BaseLoader class Loader(BaseLoader): - is_usable = True def __init__(self, engine, loaders): self.template_cache = {} diff --git a/django/template/loaders/eggs.py b/django/template/loaders/eggs.py index 42b43bab2d..4ced12936f 100644 --- a/django/template/loaders/eggs.py +++ b/django/template/loaders/eggs.py @@ -14,7 +14,11 @@ from .base import Loader as BaseLoader class Loader(BaseLoader): - is_usable = resource_string is not None + + def __init__(self, engine): + if resource_string is None: + raise RuntimeError("Setuptools must be installed to use the egg loader") + super(Loader, self).__init__(engine) def load_template_source(self, template_name, template_dirs=None): """ @@ -22,14 +26,13 @@ class Loader(BaseLoader): For every installed app, it tries to get the resource (app, template_name). """ - if resource_string is not None: - pkg_name = 'templates/' + template_name - for app_config in apps.get_app_configs(): - try: - resource = resource_string(app_config.name, pkg_name) - except Exception: - continue - if six.PY2: - resource = resource.decode(self.engine.file_charset) - return (resource, 'egg:%s:%s' % (app_config.name, pkg_name)) + pkg_name = 'templates/' + template_name + for app_config in apps.get_app_configs(): + try: + resource = resource_string(app_config.name, pkg_name) + except Exception: + continue + if six.PY2: + resource = resource.decode(self.engine.file_charset) + return (resource, 'egg:%s:%s' % (app_config.name, pkg_name)) raise TemplateDoesNotExist(template_name) diff --git a/django/template/loaders/filesystem.py b/django/template/loaders/filesystem.py index 44d814a951..4ca19d2b02 100644 --- a/django/template/loaders/filesystem.py +++ b/django/template/loaders/filesystem.py @@ -12,7 +12,6 @@ from .base import Loader as BaseLoader class Loader(BaseLoader): - is_usable = True def get_template_sources(self, template_name, template_dirs=None): """ @@ -44,4 +43,3 @@ class Loader(BaseLoader): error_msg = ("Your template directories configuration is empty. " "Change it to point to at least one template directory.") raise TemplateDoesNotExist(error_msg) - load_template_source.is_usable = True diff --git a/django/template/loaders/locmem.py b/django/template/loaders/locmem.py index 3085d69258..598907bb71 100644 --- a/django/template/loaders/locmem.py +++ b/django/template/loaders/locmem.py @@ -8,7 +8,6 @@ from .base import Loader as BaseLoader class Loader(BaseLoader): - is_usable = True def __init__(self, engine, templates_dict): self.templates_dict = templates_dict diff --git a/docs/releases/1.9.txt b/docs/releases/1.9.txt index 0ff65dec7f..eee63c6f6d 100644 --- a/docs/releases/1.9.txt +++ b/docs/releases/1.9.txt @@ -182,6 +182,16 @@ Default settings that were tuples are now lists The default settings in ``django.conf.global_settings`` were a combination of lists and tuples. All settings that were formerly tuples are now lists. +``is_usable`` attribute on template loaders is removed +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Django template loaders previously required an ``is_usable`` attribute to be +defined. If a loader was configured in the template settings and this attribute +was ``False``, the loader would be silently ignored. In practice, this was only +used by the egg loader to detect if setuptools was installed. The ``is_usable`` +attribute is now removed and the egg loader instead fails at runtime if +setuptools is not installed. + Miscellaneous ~~~~~~~~~~~~~