def conditional_response_app(self, environ, start_response):
"""
Like the normal __call__ interface, but checks conditional headers:
* If-Modified-Since (304 Not Modified; only on GET, HEAD)
* If-None-Match (304 Not Modified; only on GET, HEAD)
* Range (406 Partial Content; only on GET, HEAD)
"""
req = BaseRequest(environ)
headerlist = self._abs_headerlist(environ)
method = environ.get('REQUEST_METHOD', 'GET')
if method in self._safe_methods:
status304 = False
if req.if_none_match and self.etag:
status304 = self.etag in req.if_none_match
elif req.if_modified_since and self.last_modified:
status304 = self.last_modified <= req.if_modified_since
if status304:
start_response('304 Not Modified', filter_headers(headerlist))
return EmptyResponse(self._app_iter)
if (req.range and self in req.if_range and self.content_range is None
and method in ('HEAD', 'GET') and self.status_code == 200
and self.content_length is not None):
content_range = req.range.content_range(self.content_length)
if content_range is None:
iter_close(self._app_iter)
body = bytes_("Requested range not satisfiable: %s" %
req.range)
headerlist = [
('Content-Length', str(len(body))),
('Content-Range',
str(ContentRange(None, None, self.content_length))),
('Content-Type', 'text/plain'),
] + filter_headers(headerlist)
start_response('416 Requested Range Not Satisfiable',
headerlist)
if method == 'HEAD':
return ()
return [body]
else:
app_iter = self.app_iter_range(content_range.start,
content_range.stop)
if app_iter is not None:
# the following should be guaranteed by
# Range.range_for_length(length)
assert content_range.start is not None
headerlist = [
('Content-Length',
str(content_range.stop - content_range.start)),
('Content-Range', str(content_range)),
] + filter_headers(headerlist, ('content-length', ))
start_response('206 Partial Content', headerlist)
if method == 'HEAD':
return EmptyResponse(app_iter)
return app_iter
start_response(self.status, headerlist)
if method == 'HEAD':
return EmptyResponse(self._app_iter)
return self._app_iter
