FreeNAS Code

#+
# Copyright 2010 iXsystems, Inc.
# All rights reserved
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted providing that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# $FreeBSD$
#####################################################################
from cStringIO import StringIO
import os
import re
import sys
import cProfile

from django.conf import settings
from django.contrib.auth.decorators import login_required
from django.contrib.auth.models import User, UNUSABLE_PASSWORD
from django.contrib.auth import login, get_backends
from django.utils.cache import patch_vary_headers
from django.utils import translation

from system.models import Settings

COMMENT_SYNTAX = ((re.compile(r'^application/(.*\+)?xml|text/html$', re.I), '<!--', '-->'),
                  (re.compile(r'^application/j(avascript|son)$',     re.I), '/*',   '*/' ))

def public(f):
    f.__is_public = True
    return f

class RequireLoginMiddleware(object):
    """
    Middleware component that makes every view be login_required
    unless its decorated with @public
    """
    def process_view(self,request,view_func,view_args,view_kwargs):
        if not request.user.is_authenticated():
            user = User.objects.filter(is_superuser=True,password=UNUSABLE_PASSWORD)
            if user.exists():
                user = user[0]
                backend = get_backends()[0]
                user.backend = "%s.%s" % (backend.__module__, backend.__class__.__name__)
                login(request, user)
        if request.path == settings.LOGIN_URL:
            return None
        if hasattr(view_func, '__is_public'):
            return None
        return login_required(view_func)(request,*view_args,**view_kwargs)

class LocaleMiddleware(object):

    def process_request(self, request):
        if request.method == 'GET' and 'lang' in request.GET:
                language = request.GET['lang']
        else:
            #FIXME we could avoid this db hit using a cache,
            # invalidated when settings are edited
            language = Settings.objects.order_by('-id')[0].stg_language

        for lang in settings.LANGUAGES:
            if lang[0] == language:
                translation.activate(language)

    def process_response(self, request, response):
        patch_vary_headers(response, ('Accept-Language',))
        if 'Content-Language' not in response:
            response['Content-Language'] = translation.get_language()
        translation.deactivate()
        return response


class ProfileMiddleware(object):
    """
    Based on
    http://www.no-ack.org/2010/12/yet-another-profiling-middleware-for.html

    Changed to cProfile, instead of hotshot
    """
    def process_view(self, request, callback, args, kwargs):
        self.profiler = cProfile.Profile()
        return self.profiler.runcall(callback, request, *args, **kwargs)

    def process_response(self, request, response):

        if not hasattr(self, "profiler"):
            return response
        self.profiler.create_stats()
        out = StringIO()
        old_stdout, sys.stdout = sys.stdout, out
        self.profiler.print_stats(1)
        sys.stdout = old_stdout

        # If we have got a 3xx status code, further
        # action needs to be taken by the user agent
        # in order to fulfill the request. So don't
        # attach any stats to the content, because of
        # the content is supposed to be empty and is
        # ignored by the user agent.
        if response.status_code // 100 == 3:
            return response

        # Detect the appropriate syntax based on the
        # Content-Type header.
        for regex, begin_comment, end_comment in COMMENT_SYNTAX:
            if regex.match(response['Content-Type'].split(';')[0].strip()):
                break
        else:
            # If the given Content-Type is not
            # supported, don't attach any stats to
            # the content and return the unchanged
            # response.
            return response

        # The response can hold an iterator, that
        # is executed when the content property
        # is accessed. So we also have to profile
        # the call of the content property.
        content = out.getvalue()

        # Construct an HTML/XML or Javascript comment, with
        # the formatted stats, written to the StringIO object
        # and attach it to the content of the response.
        comment = '\n%s\n\n%s\n\n%s\n' % (begin_comment, out.getvalue(), end_comment)
        response.content += comment

        # If the Content-Length header is given, add the
        # number of bytes we have added to it. If the
        # Content-Length header is ommited or incorrect,
        # it remains so in order to don't change the
        # behaviour of the web server or user agent.
        if response.has_header('Content-Length'):
            response['Content-Length'] = int(response['Content-Length']) + len(comment)

        return response