+
−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