Fixed #25373 -- Added warning logging for exceptions during {% include %} tag rendering. (392f6484) · Commits · Dom Sekotill / django

django/template/loader_tags.py

+10 −0

Original line number	Diff line number	Diff line
		import logging
		from collections import defaultdict

		from django.utils import six
		@@ -12,6 +13,8 @@ register = Library()

		BLOCK_CONTEXT_KEY = 'block_context'

		logger = logging.getLogger('django.template')


		class ExtendsError(Exception):
		pass
		@@ -207,6 +210,13 @@ class IncludeNode(Node):
		except Exception:
		if context.template.engine.debug:
		raise
		template_name = getattr(context, 'template_name', None) or 'unknown'
		logger.warn(
		"Exception raised while rendering {%% include %%} for "
		"template '%s'. Empty string rendered instead.",
		template_name,
		exc_info=True,
		)
		return ''

docs/ref/templates/builtins.txt

+8 −3

Original line number	Diff line number	Diff line
		@@ -673,9 +673,14 @@ if it's missing or has syntax errors), the behavior varies depending on the
		:class:`template engine's <django.template.Engine>` ``debug`` option (if not
		set, this option defaults to the value of :setting:`DEBUG`). When debug mode is
		turned on, an exception like :exc:`~django.template.TemplateDoesNotExist` or
		:exc:`~django.template.TemplateSyntaxError` will be raised; otherwise
		``{% include %}`` silences any exception that happens while rendering the
		included template and returns an empty string.
		:exc:`~django.template.TemplateSyntaxError` will be raised. When debug mode
		is turned off, ``{% include %}`` logs a warning to the ``django.template``
		logger with the exception that happens while rendering the included template
		and returns an empty string.

		.. versionchanged:: 1.9

		Template logging now includes the warning logging mentioned above.

		.. note::
		The :ttag:`include` tag should be considered as an implementation of

docs/releases/1.9.txt

+9 −2

Original line number	Diff line number	Diff line
		@@ -596,8 +596,15 @@ Templates
		* Added a :meth:`Context.setdefault() <django.template.Context.setdefault>`
		method.

		* A warning will now be logged for missing context variables. These messages
		will be logged to the :ref:`django.template <django-template-logger>` logger.
		* The :ref:`django.template <django-template-logger>` logger was added and
		includes the following messages:

		* A ``DEBUG`` level message for missing context variables.

		* A ``WARNING`` level message for uncaught exceptions raised
		during the rendering of an ``{% include %}`` when debug mode is off
		(helpful since ``{% include %}`` silences the exception and returns an
		empty string).

		* The :ttag:`firstof` template tag supports storing the output in a variable
		using 'as'.

tests/template_tests/test_logging.py

+48 −3

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@ from __future__ import unicode_literals

		import logging

		from django.template import Engine, Variable, VariableDoesNotExist
		from django.template import Context, Engine, Variable, VariableDoesNotExist
		from django.test import SimpleTestCase


		@@ -15,18 +15,22 @@ class TestHandler(logging.Handler):
		self.log_record = record


		class VariableResolveLoggingTests(SimpleTestCase):
		class BaseTemplateLoggingTestCase(SimpleTestCase):
		def setUp(self):
		self.test_handler = TestHandler()
		self.logger = logging.getLogger('django.template')
		self.original_level = self.logger.level
		self.logger.addHandler(self.test_handler)
		self.logger.setLevel(logging.DEBUG)
		self.logger.setLevel(self.loglevel)

		def tearDown(self):
		self.logger.removeHandler(self.test_handler)
		self.logger.level = self.original_level


		class VariableResolveLoggingTests(BaseTemplateLoggingTestCase):
		loglevel = logging.DEBUG

		def test_log_on_variable_does_not_exist_silent(self):
		class TestObject(object):
		class SilentDoesNotExist(Exception):
		@@ -78,3 +82,44 @@ class VariableResolveLoggingTests(SimpleTestCase):
		def test_no_log_when_variable_exists(self):
		Variable('article.section').resolve({'article': {'section': 'News'}})
		self.assertIsNone(self.test_handler.log_record)


		class IncludeNodeLoggingTests(BaseTemplateLoggingTestCase):
		loglevel = logging.WARN

		@classmethod
		def setUpClass(cls):
		super(IncludeNodeLoggingTests, cls).setUpClass()
		cls.engine = Engine(loaders=[
		('django.template.loaders.locmem.Loader', {
		'child': '{{ raises_exception }}',
		}),
		], debug=False)

		def error_method():
		raise IndexError("some generic exception")

		cls.ctx = Context({'raises_exception': error_method})

		def test_logs_exceptions_during_rendering_with_debug_disabled(self):
		template = self.engine.from_string('{% include "child" %}')
		template.name = 'template_name'
		self.assertEqual(template.render(self.ctx), '')
		self.assertEqual(
		self.test_handler.log_record.getMessage(),
		"Exception raised while rendering {% include %} for template "
		"'template_name'. Empty string rendered instead."
		)
		self.assertIsNotNone(self.test_handler.log_record.exc_info)
		self.assertEqual(self.test_handler.log_record.levelno, logging.WARN)

		def test_logs_exceptions_during_rendering_with_no_template_name(self):
		template = self.engine.from_string('{% include "child" %}')
		self.assertEqual(template.render(self.ctx), '')
		self.assertEqual(
		self.test_handler.log_record.getMessage(),
		"Exception raised while rendering {% include %} for template "
		"'unknown'. Empty string rendered instead."
		)
		self.assertIsNotNone(self.test_handler.log_record.exc_info)
		self.assertEqual(self.test_handler.log_record.levelno, logging.WARN)