django1/django/template/loaders/base.py

108 lines
3.8 KiB
Python

import warnings
from django.template import Origin, Template, TemplateDoesNotExist
from django.utils.deprecation import RemovedInDjango20Warning
from django.utils.inspect import func_supports_parameter
class Loader(object):
# Only used to raise a deprecation warning. Remove in Django 1.10.
is_usable = False
_accepts_engine_in_init = True
def __init__(self, engine):
self.engine = engine
def __call__(self, template_name, template_dirs=None):
# RemovedInDjango20Warning: Allow loaders to be called like functions.
return self.load_template(template_name, template_dirs)
def get_template(self, template_name, template_dirs=None, skip=None):
"""
Calls self.get_template_sources() and returns a Template object for
the first template matching template_name. If skip is provided,
template origins in skip are ignored. This is used to avoid recursion
during template extending.
"""
tried = []
args = [template_name]
# RemovedInDjango20Warning: Add template_dirs for compatibility with
# old loaders
if func_supports_parameter(self.get_template_sources, 'template_dirs'):
args.append(template_dirs)
for origin in self.get_template_sources(*args):
if skip is not None and origin in skip:
tried.append((origin, 'Skipped'))
continue
try:
contents = self.get_contents(origin)
except TemplateDoesNotExist:
tried.append((origin, 'Source does not exist'))
continue
else:
return Template(
contents, origin, origin.template_name, self.engine,
)
raise TemplateDoesNotExist(template_name, tried=tried)
def load_template(self, template_name, template_dirs=None):
warnings.warn(
'The load_template() method is deprecated. Use get_template() '
'instead.', RemovedInDjango20Warning,
)
source, display_name = self.load_template_source(
template_name, template_dirs,
)
origin = Origin(
name=display_name,
template_name=template_name,
loader=self,
)
try:
template = Template(source, origin, template_name, self.engine)
except TemplateDoesNotExist:
# If compiling the template we found raises TemplateDoesNotExist,
# back off to returning the source and display name for the
# template we were asked to load. This allows for correct
# identification of the actual template that does not exist.
return source, display_name
else:
return template, None
def get_template_sources(self, template_name):
"""
An iterator that yields possible matching template paths for a
template name.
"""
raise NotImplementedError(
'subclasses of Loader must provide a get_template_sources() method'
)
def load_template_source(self, template_name, template_dirs=None):
"""
RemovedInDjango20Warning: Returns a tuple containing the source and
origin for the given template name.
"""
raise NotImplementedError(
'subclasses of Loader must provide a load_template_source() method'
)
def reset(self):
"""
Resets any state maintained by the loader instance (e.g. cached
templates or cached loader modules).
"""
pass
@property
def supports_recursion(self):
"""
RemovedInDjango20Warning: This is an internal property used by the
ExtendsNode during the deprecation of non-recursive loaders.
"""
return hasattr(self, 'get_contents')