app/django/middleware/gzip.py
author Sverre Rabbelier <srabbelier@gmail.com>
Wed, 05 Nov 2008 23:32:59 +0000
changeset 443 94568ac6e3e1
parent 54 03e267d67478
permissions -rw-r--r--
Implements base.Logic functions in home_settings, site_settings and work This patch implements the base.Logic funtions needed for making logic/key_name.py obsolete. This patch defines the needed functions in home_settings, site_settings and work. All modules in logic/models now have these functions defined. logic/models/site_settings.py now inherits from logic/models/home_settings.py because of their similar connection in the corresponding models. Please note that the self._keyName for these two modules still points to logic/key_name.py since entity_type is still used in views/home.py. A partial_path and link_name were added to HomeSettings as requested by SRabbelier.

import re

from django.utils.text import compress_string
from django.utils.cache import patch_vary_headers

re_accepts_gzip = re.compile(r'\bgzip\b')

class GZipMiddleware(object):
    """
    This middleware compresses content if the browser allows gzip compression.
    It sets the Vary header accordingly, so that caches will base their storage
    on the Accept-Encoding header.
    """
    def process_response(self, request, response):
        # It's not worth compressing non-OK or really short responses.
        if response.status_code != 200 or len(response.content) < 200:
            return response

        patch_vary_headers(response, ('Accept-Encoding',))

        # Avoid gzipping if we've already got a content-encoding.
        if response.has_header('Content-Encoding'):
            return response

        # Older versions of IE have issues with gzipped pages containing either
        # Javascript and PDF.
        if "msie" in request.META.get('HTTP_USER_AGENT', '').lower():
            ctype = response.get('Content-Type', '').lower()
            if "javascript" in ctype or ctype == "application/pdf":
                return response

        ae = request.META.get('HTTP_ACCEPT_ENCODING', '')
        if not re_accepts_gzip.search(ae):
            return response

        response.content = compress_string(response.content)
        response['Content-Encoding'] = 'gzip'
        response['Content-Length'] = str(len(response.content))
        return response