from django.template import Template, TemplateDoesNotExist
class Loader:
def __init__(self, engine):
self.engine = engine
def get_template(self, template_name, skip=None):
"""
Call self.get_template_sources() and return a Template object for
the first template matching template_name. If skip is provided, ignore
template origins in skip. This is used to avoid recursion during
template extending.
"""
tried = []
for origin in self.get_template_sources(template_name):
if skip is not None and origin in skip:
tried.append((origin, "Skipped to avoid recursion"))
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 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 reset(self):
"""
Reset any state maintained by the loader instance (e.g. cached
templates or cached loader modules).
"""
pass