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

1099 by matt.giuca
dispatch/__init__.py: Updated header comments to new policy, updated copyright.
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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2009 The University of Melbourne
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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# Author: Matt Giuca, Will Grant
1099 by matt.giuca
dispatch/__init__.py: Updated header comments to new policy, updated copyright.
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"""
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This is a mod_python handler program. The correct way to call it is to have
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Apache send all requests to be handled by the module 'dispatch'.
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Top-level handler. Handles all requests to all pages in IVLE.
1099.1.166 by William Grant
Remove the odd handler() -> handler_() chaining in ivle.dispatch.
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Handles authentication and delegates to views for authorization,
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then passes the request along to the appropriate view.
1099 by matt.giuca
dispatch/__init__.py: Updated header comments to new policy, updated copyright.
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"""
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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import sys
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import os
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import os.path
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import urllib
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import cgi
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import traceback
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import logging
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import socket
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import time
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import mod_python
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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import routes
1079 by William Grant
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from ivle import util
1199 by William Grant
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import ivle.config
1099.1.5 by William Grant
ivle.dispatch{,.{login,request}}: Fix mod_python imports to ensure that we can
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from ivle.dispatch.request import Request
1099.1.161 by William Grant
Move ivle.dispatch.login.get_user_details() to ivle.webapp.security.
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import ivle.webapp.security
1099.1.146 by William Grant
Add support for public mode views to the new framework.
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from ivle.webapp.base.plugins import ViewPlugin, PublicViewPlugin
1099.1.202 by William Grant
XHTMLErrorView is now the default error view, so we get nice 404s.
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from ivle.webapp.base.xhtml import XHTMLView, XHTMLErrorView
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from ivle.webapp.errors import HTTPError, Unauthorized, NotFound
1079 by William Grant
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1199 by William Grant
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config = ivle.config.Config()
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def generate_router(view_plugins, attr):
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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    """
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    Build a Mapper object for doing URL matching using 'routes', based on the
1099.1.59 by William Grant
Provide a media file framework in ivle.webapp.media.
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    given plugin registry.
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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    """
1099.1.13 by William Grant
ivle.dispatch: Throw the routes mapper into req.mapper, and make it explicit.
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    m = routes.Mapper(explicit=True)
1099.1.72 by Nick Chadwick
Dispatch now generates an index for each plugin type, allowing plugins to
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    for plugin in view_plugins:
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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        # Establish a URL pattern for each element of plugin.urls
1099.1.72 by Nick Chadwick
Dispatch now generates an index for each plugin type, allowing plugins to
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        assert hasattr(plugin, 'urls'), "%r does not have any urls" % plugin 
1099.1.146 by William Grant
Add support for public mode views to the new framework.
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        for url in getattr(plugin, attr):
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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            routex = url[0]
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            view_class = url[1]
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            kwargs_dict = url[2] if len(url) >= 3 else {}
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            m.connect(routex, view=view_class, **kwargs_dict)
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    return m
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1099.1.166 by William Grant
Remove the odd handler() -> handler_() chaining in ivle.dispatch.
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def handler(apachereq):
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    """Handles an HTTP request.
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1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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    Intended to be called by mod_python, as a handler.
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1099.1.166 by William Grant
Remove the odd handler() -> handler_() chaining in ivle.dispatch.
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    @param apachereq: An Apache request object.
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    """
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    # Make the request object into an IVLE request which can be given to views
1199 by William Grant
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    req = Request(apachereq, config)
1099.1.166 by William Grant
Remove the odd handler() -> handler_() chaining in ivle.dispatch.
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1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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    # Hack? Try and get the user login early just in case we throw an error
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    # (most likely 404) to stop us seeing not logged in even when we are.
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    if not req.publicmode:
1099.1.161 by William Grant
Move ivle.dispatch.login.get_user_details() to ivle.webapp.security.
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        user = ivle.webapp.security.get_user_details(req)
1099.1.121 by William Grant
Don't set req.user unless the login in the session specifies a valid user.
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        # Don't set the user if it is disabled or hasn't accepted the ToS.
1099.1.123 by William Grant
Don't crash when not authenticated, and display an error on password absence.
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        if user and user.valid:
1099.1.121 by William Grant
Don't set req.user unless the login in the session specifies a valid user.
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            req.user = user
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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1099.1.146 by William Grant
Add support for public mode views to the new framework.
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    if req.publicmode:
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        req.mapper = generate_router(config.plugin_index[PublicViewPlugin],
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                                    'public_urls')
1099.1.146 by William Grant
Add support for public mode views to the new framework.
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    else:
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Populate req.config in a cleaner manner.
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        req.mapper = generate_router(config.plugin_index[ViewPlugin], 'urls')
1099.1.59 by William Grant
Provide a media file framework in ivle.webapp.media.
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1099.1.13 by William Grant
ivle.dispatch: Throw the routes mapper into req.mapper, and make it explicit.
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    matchdict = req.mapper.match(req.uri)
1099.1.1 by Matt Giuca
Began implementing new dispatch framework (with Will Grant and Nick Chadwick).
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    if matchdict is not None:
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        viewcls = matchdict['view']
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        # Get the remaining arguments, less 'view', 'action' and 'controller'
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        # (The latter two seem to be built-in, and we don't want them).
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        kwargs = matchdict.copy()
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        del kwargs['view']
1099.1.84 by William Grant
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        try:
1099.1.86 by William Grant
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            # Instantiate the view, which should be a BaseView class
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            view = viewcls(req, **kwargs)
1099.1.110 by William Grant
Implement an authorization system in the new framework. This breaks the REST
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            # Check that the request (mainly the user) is permitted to access
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            # the view.
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            if not view.authorize(req):
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                raise Unauthorized()
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            # Render the output
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            view.render(req)
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        except HTTPError, e:
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            # A view explicitly raised an HTTP error. Respect it.
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            req.status = e.code
1099.1.91 by William Grant
Add support for custom error views. Plugins can now declare that errors
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            # Try to find a custom error view.
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Error views are now retrieved from a class method of the view, not the plugin
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            if hasattr(viewcls, 'get_error_view'):
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                errviewcls = viewcls.get_error_view(e)
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            else:
1099.1.202 by William Grant
XHTMLErrorView is now the default error view, so we get nice 404s.
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                errviewcls = XHTMLView.get_error_view(e)
1099.1.95 by William Grant
Error views are now retrieved from a class method of the view, not the plugin
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1099.1.91 by William Grant
Add support for custom error views. Plugins can now declare that errors
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            if errviewcls:
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                errview = errviewcls(req, e)
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                errview.render(req)
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                return req.OK
1099.1.135 by William Grant
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            elif e.message:
1099.1.91 by William Grant
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                req.write(e.message)
1099.1.135 by William Grant
In the new framework handler, either write the exception message or use
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                return req.OK
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            else:
1099.1.91 by William Grant
Add support for custom error views. Plugins can now declare that errors
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                return e.code
1155 by William Grant
Don't handle mod_python exceptions (eg. redirects) as unknown exceptions.
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        except mod_python.apache.SERVER_RETURN:
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            # A mod_python-specific Apache error.
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            # XXX: We need to raise these because req.throw_error() uses them.
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            # Remove this after Google Code issue 117 is fixed.
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            raise
1099.1.84 by William Grant
Handle HTTPErrors nicely in the new framework. Currently there is no facility
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        except Exception, e:
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            # A non-HTTPError appeared. We have an unknown exception. Panic.
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            handle_unknown_exception(req, *sys.exc_info())
1099.1.88 by William Grant
Make sure that we don't use the old framework if the new framework crashes.
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            return req.OK
1099.1.84 by William Grant
Handle HTTPErrors nicely in the new framework. Currently there is no facility
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        else:
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            req.store.commit()
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            return req.OK
1099.1.149 by William Grant
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    else:
1296 by William Grant
Actually 404 when a matching route is not found.
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        req.status = 404
1099.1.202 by William Grant
XHTMLErrorView is now the default error view, so we get nice 404s.
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        XHTMLErrorView(req, NotFound()).render(req)
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        return req.OK
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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def handle_unknown_exception(req, exc_type, exc_value, exc_traceback):
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    """
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    Given an exception that has just been thrown from IVLE, print its details
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    to the request.
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    This is a full handler. It assumes nothing has been written, and writes a
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    complete HTML page.
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    req: May be EITHER an IVLE req or an Apache req.
1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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    The handler code may pass an apache req if an exception occurs before
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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    the IVLE request is created.
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    """
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    req.content_type = "text/html"
1199 by William Grant
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    logfile = os.path.join(config['paths']['logs'], 'ivle_error.log')
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    logfail = False
1292 by William Grant
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    # XXX: This remains here for ivle.interpret's IVLEErrors. Once we rewrite
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    #      fileservice, req.status should always be 500 (ISE) here.
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    try:
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        httpcode = exc_value.httpcode
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        req.status = httpcode
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    except AttributeError:
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        httpcode = None
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        req.status = mod_python.apache.HTTP_INTERNAL_SERVER_ERROR
1286 by William Grant
Simplify (and deprettify) the crash handler. It's now only used to handle crashes, so needn't be pretty.
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1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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    try:
1087 by chadnickbok
Fixes Issue #3
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        publicmode = req.publicmode
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    except AttributeError:
1088 by chadnickbok
Fixed an issue with my previous patch to this file. Now, if
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        publicmode = True
1087 by chadnickbok
Fixes Issue #3
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    try:
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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        login = req.user.login
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    except AttributeError:
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        login = None
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    # Log File
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    try:
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        for h in logging.getLogger().handlers:
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            logging.getLogger().removeHandler(h)
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        logging.basicConfig(level=logging.INFO,
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            format='%(asctime)s %(levelname)s: ' +
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                '(HTTP: ' + str(req.status) +
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                ', Ref: ' + str(login) + '@' +
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                str(socket.gethostname()) + str(req.uri) +
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                ') %(message)s',
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            filename=logfile,
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            filemode='a')
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    except IOError:
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        logfail = True
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1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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    # A "bad" error message. We shouldn't get here unless IVLE
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    # misbehaves (which is currently very easy, if things aren't set up
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    # correctly).
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    # Write the traceback.
1286 by William Grant
Simplify (and deprettify) the crash handler. It's now only used to handle crashes, so needn't be pretty.
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    # We need to special-case IVLEJailError, as we can get another
1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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    # almost-exception out of it.
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    if exc_type is util.IVLEJailError:
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        tb = 'Exception information extracted from IVLEJailError:\n'
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        tb += urllib.unquote(exc_value.info)
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    else:
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        tb = ''.join(traceback.format_exception(exc_type, exc_value,
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                                                exc_traceback))
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1286 by William Grant
Simplify (and deprettify) the crash handler. It's now only used to handle crashes, so needn't be pretty.
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    logging.error('\n' + tb)
1099.1.167 by William Grant
Simplify and prettify the crash handler.
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1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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    # Error messages are only displayed is the user is NOT a student,
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    # or if there has been a problem logging the error message
1101 by William Grant
Privileges (apart from admin) are now offering-local, not global.
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    show_errors = (not publicmode) and ((login and req.user.admin) or logfail)
1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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    req.write("""<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"                 
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">                                      
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head><title>IVLE Internal Server Error</title></head>
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<body>
1286 by William Grant
Simplify (and deprettify) the crash handler. It's now only used to handle crashes, so needn't be pretty.
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<h1>IVLE Internal Server Error</h1>
1079 by William Grant
Merge setup-refactor branch. This completely breaks existing installations;
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<p>An error has occured which is the fault of the IVLE developers or
1099.1.175 by William Grant
Alter the crash handler to display a different message depending on whether
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administrators. """)
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    if logfail:
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        req.write("Please report this issue to the server administrators, "
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                  "along with the following information.")
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    else:
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        req.write("Details have been logged for further examination.")
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    req.write("</p>")
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1099.1.167 by William Grant
Simplify and prettify the crash handler.
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    if show_errors:
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        req.write("<h2>Debugging information</h2>")
1099.1.157 by William Grant
Drop the 4xx-series exception handling ability from
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        req.write("<pre>\n%s\n</pre>\n"%cgi.escape(tb))
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    req.write("</body></html>")