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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2009 The University of Melbourne
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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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# 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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# 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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# Author: Matt Giuca, Will Grant
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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.
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Handles authentication (not authorization).
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Then passes the request along to the appropriate ivle app.
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from ivle.dispatch.request import Request
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from ivle.dispatch import login
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from ivle.webapp.base.plugins import ViewPlugin
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from ivle.webapp.errors import HTTPError, Unauthorized
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# XXX List of plugins, which will eventually be read in from conf
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'ivle.webapp.core#Plugin',
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'ivle.webapp.admin.user#Plugin',
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'ivle.webapp.tutorial#Plugin',
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'ivle.webapp.admin.subject#Plugin',
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'ivle.webapp.filesystem.browser#Plugin',
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'ivle.webapp.filesystem.diff#Plugin',
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'ivle.webapp.filesystem.svnlog#Plugin',
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'ivle.webapp.groups#Plugin',
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'ivle.webapp.console#Plugin',
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'ivle.webapp.security#Plugin',
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'ivle.webapp.media#Plugin',
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'ivle.webapp.forum#Plugin',
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'ivle.webapp.help#Plugin',
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'ivle.webapp.tos#Plugin',
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def generate_route_mapper(view_plugins):
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Build a Mapper object for doing URL matching using 'routes', based on the
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given plugin registry.
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m = routes.Mapper(explicit=True)
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for plugin in view_plugins:
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# Establish a URL pattern for each element of plugin.urls
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assert hasattr(plugin, 'urls'), "%r does not have any urls" % plugin
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for url in plugin.urls:
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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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def get_plugin(pluginstr):
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plugin_path, classname = pluginstr.split('#')
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# Load the plugin module from somewhere in the Python path
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# (Note that plugin_path is a fully-qualified Python module name).
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getattr(__import__(plugin_path, fromlist=[classname]), classname))
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"""Handles a request which may be to anywhere in the site except media.
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Intended to be called by mod_python, as a handler.
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req: An Apache request object.
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# Make the request object into an IVLE request which can be passed to apps
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req = Request(req, html.write_html_head)
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# Pass the apachereq to error reporter, since ivle req isn't created
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handle_unknown_exception(apachereq, *sys.exc_info())
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# Tell Apache not to generate its own errors as well
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return mod_python.apache.OK
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# Run the main handler, and catch all exceptions
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return handler_(req, apachereq)
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except mod_python.apache.SERVER_RETURN:
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# An apache error. We discourage these, but they might still happen.
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handle_unknown_exception(req, *sys.exc_info())
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# Tell Apache not to generate its own errors as well
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return mod_python.apache.OK
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def handler_(req, apachereq):
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Nested handler function. May raise exceptions. The top-level handler is
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just used to catch exceptions.
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Takes both an IVLE request and an Apache req.
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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:
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req.user = login.get_user_details(req)
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### BEGIN New plugins framework ###
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# XXX This should be done ONCE per Python process, not per request.
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# XXX No authentication is done here
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req.plugins = dict([get_plugin(pluginstr) for pluginstr in plugins_HACK])
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# Index the plugins by base class
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req.plugin_index = {}
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for plugin in req.plugins.values():
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# Getmro returns a tuple of all the super-classes of the plugin
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for base in inspect.getmro(plugin):
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if base not in req.plugin_index:
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req.plugin_index[base] = []
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req.plugin_index[base].append(plugin)
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req.reverse_plugins = dict([(v, k) for (k, v) in req.plugins.items()])
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req.mapper = generate_route_mapper(req.plugin_index[ViewPlugin])
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matchdict = req.mapper.match(req.uri)
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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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# Instantiate the view, which should be a BaseView class
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view = viewcls(req, **kwargs)
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# Check that the request (mainly the user) is permitted to access
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if not view.authorize(req):
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# A view explicitly raised an HTTP error. Respect it.
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# Try to find a custom error view.
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if hasattr(viewcls, 'get_error_view'):
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errviewcls = viewcls.get_error_view(e)
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errview = errviewcls(req, 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())
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### END New plugins framework ###
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# Check req.app to see if it is valid. 404 if not.
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if req.app is not None and req.app not in ivle.conf.apps.app_url:
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req.throw_error(Request.HTTP_NOT_FOUND,
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"There is no application called %s." % repr(req.app))
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# Special handling for public mode - only allow the public app, call it
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# NOTE: This will not behave correctly if the public app uses
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# write_html_head_foot, but "serve" does not.
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if req.app != ivle.conf.apps.public_app:
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req.throw_error(Request.HTTP_FORBIDDEN,
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"This application is not available on the public site.")
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app = ivle.conf.apps.app_url[ivle.conf.apps.public_app]
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apps.call_app(app.dir, req)
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# app is the App object for the chosen app
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app = ivle.conf.apps.app_url[ivle.conf.apps.default_app]
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app = ivle.conf.apps.app_url[req.app]
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# Check if app requires auth. If so, perform authentication and login.
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# This will either return a User object, None, or perform a redirect
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# which we will not catch here.
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req.user = login.login(req)
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logged_in = req.user is not None
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req.user = login.get_user_details(req)
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# Keep the user's session alive by writing to the session object.
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# req.get_session().save()
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# Well, it's a fine idea, but it creates considerable grief in the
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# concurrent update department, so instead, we'll just make the
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# sessions not time out.
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req.get_session().unlock()
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# If user did not specify an app, HTTP redirect to default app and
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req.throw_redirect(util.make_path(ivle.conf.apps.default_app))
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# Set the default title to the app's tab name, if any. Otherwise URL
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if app.name is not None:
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# Call the specified app with the request object
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apps.call_app(app.dir, req)
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# if not logged in, login.login will have written the login box.
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# Just clean up and exit.
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# MAKE SURE we write the HTTP (and possibly HTML) header. This
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# wouldn't happen if nothing else ever got written, so we have to make
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req.ensure_headers_written()
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# When done, write out the HTML footer if the app has requested it
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if req.write_html_head_foot:
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html.write_html_foot(req)
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# Note: Apache will not write custom HTML error messages here.
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# Use req.throw_error to do that.
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def handle_unknown_exception(req, exc_type, exc_value, exc_traceback):
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Given an exception that has just been thrown from IVLE, print its details
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This is a full handler. It assumes nothing has been written, and writes a
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req: May be EITHER an IVLE req or an Apache req.
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IVLE reqs may have the HTML head/foot written (on a 400 error), but
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the handler code may pass an apache req if an exception occurs before
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the IVLE request is created.
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req.content_type = "text/html"
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logfile = os.path.join(ivle.conf.log_path, 'ivle_error.log')
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# For some reason, some versions of mod_python have "_server" instead of
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# "main_server". So we check for both.
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admin_email = mod_python.apache.main_server.server_admin
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except AttributeError:
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admin_email = mod_python.apache._server.server_admin
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except AttributeError:
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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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req.status = mod_python.apache.HTTP_INTERNAL_SERVER_ERROR
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publicmode = req.publicmode
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except AttributeError:
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login = req.user.login
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except AttributeError:
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except AttributeError:
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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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logging.debug('Logging Unhandled Exception')
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# We handle 3 types of error.
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# IVLEErrors with 4xx response codes (client error).
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# IVLEErrors with 5xx response codes (handled server error).
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# Other exceptions (unhandled server error).
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# IVLEErrors should not have other response codes than 4xx or 5xx
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# (eg. throw_redirect should have been used for 3xx codes).
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# Therefore, that is treated as an unhandled error.
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if (exc_type == util.IVLEError and httpcode >= 400
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and httpcode <= 499):
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# IVLEErrors with 4xx response codes are client errors.
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# Therefore, these have a "nice" response (we even coat it in the IVLE
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req.write_html_head_foot = True
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req.write_javascript_settings = False
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req.write('<div id="ivle_padding">\n')
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codename, msg = req.get_http_codename(httpcode)
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except AttributeError:
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codename, msg = None, None
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# Override the default message with the supplied one,
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if exc_value.message is not None:
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msg = exc_value.message
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if codename is not None:
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req.write("<h1>Error: %s</h1>\n" % cgi.escape(codename))
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req.write("<h1>Error</h1>\n")
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req.write("<p>%s</p>\n" % cgi.escape(msg))
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req.write("<p>An unknown error occured.</p>\n")
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logging.info(str(msg))
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req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
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req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
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%cgi.escape(logfile))
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req.write('</div>\n')
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html.write_html_foot(req)
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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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# Write the traceback.
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# If this is a non-4xx IVLEError, get the message and httpcode and
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# make the error message a bit nicer (but still include the
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# We also need to special-case IVLEJailError, as we can get another
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# almost-exception out of it.
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codename, msg = None, None
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if exc_type is util.IVLEJailError:
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msg = exc_value.type_str + ": " + exc_value.message
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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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codename, msg = req.get_http_codename(httpcode)
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except AttributeError:
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# Override the default message with the supplied one,
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if hasattr(exc_value, 'message') and exc_value.message is not None:
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msg = exc_value.message
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# Prepend the exception type
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if exc_type != util.IVLEError:
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msg = exc_type.__name__ + ": " + msg
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tb = ''.join(traceback.format_exception(exc_type, exc_value,
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logging.error('%s\n%s'%(str(msg), tb))
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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
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show_errors = (not publicmode) and ((login and \
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str(role) != "student") or logfail)
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req.write("""<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
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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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<h1>IVLE Internal Server Error""")
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if (codename is not None
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and httpcode != mod_python.apache.HTTP_INTERNAL_SERVER_ERROR):
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req.write(": %s" % cgi.escape(codename))
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<p>An error has occured which is the fault of the IVLE developers or
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administration. The developers have been notified.</p>
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req.write("<p>%s</p>\n" % cgi.escape(msg))
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if httpcode is not None:
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req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
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<p>Please report this to <a href="mailto:%s">%s</a> (the system
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administrator). Include the following information:</p>
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""" % (cgi.escape(admin_email), cgi.escape(admin_email)))
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req.write("<pre>\n%s\n</pre>\n"%cgi.escape(tb))
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req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
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%cgi.escape(logfile))
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req.write("</body></html>")
added
removed
ivle/dispatch/__init__.py
