~azzar1/unity/add-show-desktop-key

# IVLE

# Copyright (C) 2007-2009 The University of Melbourne

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

# Author: Will Grant, Nick Chadwick

import urllib

import datetime

try:

    import mod_python.Cookie

except ImportError:

    # This needs to be importable from outside Apache.

    pass

import ivle.pulldown_subj

import ivle.webapp.security

from ivle.auth import authenticate, AuthError

from ivle.webapp.base.xhtml import XHTMLView

from ivle.webapp.base.plugins import CookiePlugin

class LoginView(XHTMLView):

    '''A view to allow a user to log in.'''

    template = 'login.html'

    allow_overlays = False

    def authorize(self, req):

        return True

    def populate(self, req, ctx):

        fields = req.get_fieldstorage()

        nexturl = fields.getfirst('url')

        # XXX Warning that Internet Explorer is unsupported

        # Test if the user is in Internet Explorer

        try:

            useragent = req.headers_in['User-Agent']

            # A bit of very basic UA string detection

            ctx['msie'] = ('MSIE' in useragent

                           and 'AppleWebKit' not in useragent

                           and 'Gecko' not in useragent

                           and 'Opera' not in useragent)

        except KeyError:

            ctx['msie'] = False

        if nexturl is None:

            nexturl = '/'

        # We are already logged in. If it is a POST, they might be trying to

        # clobber their session with some new credentials. That's their own

        # business, so we let them do it. Otherwise, we don't bother prompting

        # and just redirect to the destination.

        # Note that req.user is None even if we are 'logged in', if the user is

        # invalid (state != enabled, or expired).

        if req.method != "POST" and req.user is not None:

            req.throw_redirect(nexturl)

        # Don't give any URL if we want /.

        if nexturl == '/':

            query_string = ''

        else:

            query_string = '?url=' + urllib.quote(nexturl, safe="/~")

        ctx['path'] = req.make_path('+login') + query_string

        # If this succeeds, the user is invalid.

        user = ivle.webapp.security.get_user_details(req)

        if user is not None:

            if user.state == "no_agreement":

                # Authenticated, but need to accept the ToS. Send them there.

                # IMPORTANT NOTE FOR HACKERS: You can't simply disable this

                # if you are not planning to display a ToS page - the ToS

                # acceptance process actually calls usrmgt to create the user

                # jails and related stuff.

                req.throw_redirect(req.make_path('+tos') + query_string)

            elif user.state == "pending":

                # FIXME: this isn't quite the right answer, but it

                # should be more robust in the short term.

                session = req.get_session()

                session.invalidate()

                session.delete()

                user.state = u'no_agreement'

                req.store.commit()

                req.throw_redirect(nexturl)

        if req.method == "POST":

            # While req.user is normally set to get_user_details, it won't set

            # it if the account isn't valid. So we get it ourselves.

            user = ivle.webapp.security.get_user_details(req)

            badlogin = None

            username = fields.getfirst('user')

            password = fields.getfirst('pass')

            if username is not None:

                # From this point onwards, we will be showing an error message

                # if unsuccessful.

                # Authenticate

                if password is None:

                    badlogin = "No password supplied."

                else:

                    user = None

                    try:

                        # Username is case insensitive

                        user = authenticate.authenticate(req.config, req.store,

                                    username.value.lower(), password.value)

                    except AuthError, msg:

                        badlogin = msg

                    if user is None:

                        # Must have got an error. Do not authenticate.

                        # The except: above will have set a message.

                        pass

                    else:

                        # Success - Set the session and redirect to the URL.

                        session = req.get_session()

                        session['login'] = user.login

                        session.save()

                        session.unlock()

                        user.last_login = datetime.datetime.now()

                        # Create cookies for plugins that might request them.

                        for plugin in req.config.plugin_index[CookiePlugin]:

                            for cookie in plugin.cookies:

                                # The function can be None if they just need to be

                                # deleted at logout.

                                if plugin.cookies[cookie] is not None:

                                    req.add_cookie(mod_python.Cookie.Cookie(cookie,

                                          plugin.cookies[cookie](user), path='/'))

                        # Add any new enrolments.

                        ivle.pulldown_subj.enrol_user(req.config, req.store, user)

                        req.store.commit()

                        req.throw_redirect(nexturl)

                # We didn't succeed.

                # Render the login form with the error message.

                ctx['error'] = badlogin

class LogoutView(XHTMLView):

    '''A view to log the current session out.'''

    template = 'logout.html'

    allow_overlays = False

    def authorize(self, req):

        # This can be used by any authenticated user, even if they haven't

        # accepted the ToS yet.

        return ivle.webapp.security.get_user_details(req) is not None

    def populate(self, req, ctx):

        if req.method == "POST":

            req.logout()

        else:

            ctx['path'] =  req.make_path('+logout')