Commit 8975bba7 authored by Malcolm Tredinnick's avatar Malcolm Tredinnick
Browse files

Fixed #4148 -- Changed the way attachments are served to IE to avoid some 

caching and header-related bugs there. Only comes into play when Internet
Explorer is the user-agent.

Patch from Michael Axiak, with testing from Axis_of_Entropy and Karen Tracey.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@7856 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 60483893

django/core/handlers/base.py

+6 −2
Original line number Diff line number Diff line
@@ -6,8 +6,12 @@ from django.dispatch import dispatcher 


class BaseHandler(object):

    # Changes that are always applied to a response (in this order).

    response_fixes = [http.fix_location_header,

            http.conditional_content_removal]

    response_fixes = [

        http.fix_location_header,

        http.conditional_content_removal,

        http.fix_IE_for_attach,

        http.fix_IE_for_vary,

    ]



    def __init__(self):

        self._request_middleware = self._view_middleware = self._response_middleware = self._exception_middleware = None

django/http/utils.py

+51 −0
Original line number Diff line number Diff line
@@ -31,3 +31,54 @@ def conditional_content_removal(request, response): 
    if request.method == 'HEAD':

        response.content = ''

    return response



def fix_IE_for_attach(request, response):

    """

    This function will prevent Django from serving a Content-Disposition header

    while expecting the browser to cache it (only when the browser is IE). This

    leads to IE not allowing the client to download.

    """

    if 'MSIE' not in request.META.get('HTTP_USER_AGENT', '').upper():

        return response



    offending_headers = ('no-cache', 'no-store')

    if response.has_header('Content-Disposition'):

        try:

            del response['Pragma']

        except KeyError:

            pass

        if response.has_header('Cache-Control'):

            cache_control_values = [value.strip() for value in

                    response['Cache-Control'].split(',')

                    if value.strip().lower() not in offending_headers]



            if not len(cache_control_values):

                del response['Cache-Control']

            else:

                response['Cache-Control'] = ', '.join(cache_control_values)



    return response



def fix_IE_for_vary(request, response):

    """

    This function will fix the bug reported at

    http://support.microsoft.com/kb/824847/en-us?spid=8722&sid=global

    by clearing the Vary header whenever the mime-type is not safe

    enough for Internet Explorer to handle.  Poor thing.

    """

    if 'MSIE' not in request.META.get('HTTP_USER_AGENT', '').upper():

        return response



    # These mime-types that are decreed "Vary-safe" for IE:

    safe_mime_types = ('text/html', 'text/plain', 'text/sgml')



    # The first part of the Content-Type field will be the MIME type,

    # everything after ';', such as character-set, can be ignored.

    if response['Content-Type'].split(';')[0] not in safe_mime_types:

        try:

            del response['Vary']

        except KeyError:

            pass



    return response