django1/django/template/response.py

109 lines
4.2 KiB
Python

from django.http import HttpResponse
from django.template import loader, Context, RequestContext
class ContentNotRenderedError(Exception):
pass
class SimpleTemplateResponse(HttpResponse):
def __init__(self, template, context=None, mimetype=None, status=None,
content_type=None):
# It would seem obvious to call these next two members 'template' and
# 'context', but those names are reserved as part of the test Client API.
# To avoid the name collision, we use
# tricky-to-debug problems
self.template_name = template
self.context_data = context
# _is_rendered tracks whether the template and context has been baked into
# a final response.
self._is_rendered = False
# content argument doesn't make sense here because it will be replaced
# with rendered template so we always pass empty string in order to
# prevent errors and provide shorter signature.
super(SimpleTemplateResponse, self).__init__('', mimetype, status,
content_type)
def resolve_template(self, template):
"Accepts a template object, path-to-template or list of paths"
if isinstance(template, (list, tuple)):
return loader.select_template(template)
elif isinstance(template, basestring):
return loader.get_template(template)
else:
return template
def resolve_context(self, context):
"""Convert context data into a full Context object
(assuming it isn't already a Context object).
"""
if isinstance(context, Context):
return context
else:
return Context(context)
@property
def rendered_content(self):
"""Returns the freshly rendered content for the template and context
described by the TemplateResponse.
This *does not* set the final content of the response. To set the
response content, you must either call render(), or set the
content explicitly using the value of this property.
"""
template = self.resolve_template(self.template_name)
context = self.resolve_context(self.context_data)
content = template.render(context)
return content
def render(self):
"""Render (thereby finalizing) the content of the response.
If the content has already been rendered, this is a no-op.
Returns the baked response instance.
"""
if not self._is_rendered:
self._set_content(self.rendered_content)
return self
is_rendered = property(lambda self: self._is_rendered)
def __iter__(self):
if not self._is_rendered:
raise ContentNotRenderedError('The response content must be rendered before it can be iterated over.')
return super(SimpleTemplateResponse, self).__iter__()
def _get_content(self):
if not self._is_rendered:
raise ContentNotRenderedError('The response content must be rendered before it can be accessed.')
return super(SimpleTemplateResponse, self)._get_content()
def _set_content(self, value):
"Overrides rendered content, unless you later call render()"
super(SimpleTemplateResponse, self)._set_content(value)
self._is_rendered = True
content = property(_get_content, _set_content)
class TemplateResponse(SimpleTemplateResponse):
def __init__(self, request, template, context=None, mimetype=None,
status=None, content_type=None):
# self.request gets over-written by django.test.client.Client - and
# unlike context_data and template_name the _request should not
# be considered part of the public API.
self._request = request
super(TemplateResponse, self).__init__(
template, context, mimetype, status, content_type)
def resolve_context(self, context):
"""Convert context data into a full RequestContext object
(assuming it isn't already a Context object).
"""
if isinstance(context, Context):
return context
else:
return RequestContext(self._request, context)