django1/django/middleware/http.py

38 lines
1.4 KiB
Python

import datetime
class ConditionalGetMiddleware:
"""
Handles conditional GET operations. If the response has a ETag or
Last-Modified header, and the request has If-None-Match or
If-Modified-Since, the response is replaced by an HttpNotModified.
Removes the content from any response to a HEAD request.
Also sets the Date and Content-Length response-headers.
"""
def process_response(self, request, response):
now = datetime.datetime.utcnow()
response['Date'] = now.strftime('%a, %d %b %Y %H:%M:%S GMT')
if not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
if response.has_header('ETag'):
if_none_match = request.META.get('HTTP_IF_NONE_MATCH', None)
if if_none_match == response['ETag']:
response.status_code = 304
response.content = ''
response['Content-Length'] = '0'
if response.has_header('Last-Modified'):
last_mod = response['Last-Modified']
if_modified_since = request.META.get('HTTP_IF_MODIFIED_SINCE', None)
if if_modified_since == response['Last-Modified']:
response.status_code = 304
response.content = ''
response['Content-Length'] = '0'
if request.META['REQUEST_METHOD'] == 'HEAD':
response.content = ''
return response