22
22
Apache send all requests to be handled by the module 'dispatch'.
24
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Top-level handler. Handles all requests to all pages in IVLE.
25
Handles authentication (not authorization).
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Then passes the request along to the appropriate ivle app.
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Handles authentication and delegates to views for authorization,
26
then passes the request along to the appropriate view.
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from ivle import util
46
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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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import ivle.webapp.security
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from ivle.webapp.base.plugins import ViewPlugin, PublicViewPlugin
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from ivle.webapp.base.xhtml import XHTMLView, XHTMLErrorView
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from ivle.webapp.errors import BadRequest, HTTPError, NotFound, Unauthorized
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from ivle.webapp.publisher import Publisher, PublishingError
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from ivle.webapp import ApplicationRoot
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config = ivle.config.Config()
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class ObjectPermissionCheckingPublisher(Publisher):
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"""A specialised publisher that checks object permissions.
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This publisher verifies that the user holds any permission at all
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on the model objects through which the resolution path passes. If
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no permission is held, resolution is aborted with an Unauthorized
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IMPORTANT: This does NOT check view permissions. It only checks
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the objects in between the root and the view, exclusive!
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def traversed_to_object(self, obj):
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"""Check that the user has any permission at all over the object."""
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if (hasattr(obj, 'get_permissions') and
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len(obj.get_permissions(self.root.user, config)) == 0):
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# Indicate the forbidden object if this is an admin.
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if self.root.user and self.root.user.admin:
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raise Unauthorized('Unauthorized: %s' % obj)
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def generate_publisher(view_plugins, root, publicmode=False):
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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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r = ObjectPermissionCheckingPublisher(root=root)
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r.add_set_switch('api', 'api')
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view_attr = 'public_views'
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forward_route_attr = 'public_forward_routes'
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reverse_route_attr = 'public_reverse_routes'
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forward_route_attr = 'forward_routes'
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reverse_route_attr = 'reverse_routes'
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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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if hasattr(plugin, forward_route_attr):
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for fr in getattr(plugin, forward_route_attr):
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# An annotated function can also be passed in directly.
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if hasattr(fr, '_forward_route_meta'):
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r.add_forward_func(fr)
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if hasattr(plugin, reverse_route_attr):
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for rr in getattr(plugin, reverse_route_attr):
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# An annotated function can also be passed in directly.
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if hasattr(rr, '_reverse_route_src'):
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r.add_reverse_func(rr)
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if hasattr(plugin, view_attr):
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for v in getattr(plugin, view_attr):
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def handler(apachereq):
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"""Handles an HTTP request.
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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
121
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
126
just used to catch exceptions.
127
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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@param apachereq: An Apache request object.
126
# Make the request object into an IVLE request which can be given to views
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req = Request(apachereq, config)
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req.publisher = generate_publisher(
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config.plugin_index[ViewPlugin], ApplicationRoot(req),
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publicmode=req.publicmode)
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obj, viewcls, subpath = req.publisher.resolve(req.uri.decode('utf-8'))
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# We 404 if we have a subpath but the view forbids it.
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if not viewcls.subpath_allowed and subpath:
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# Instantiate the view, which should be a BaseView class
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view = viewcls(req, **kwargs)
141
view = viewcls(req, obj, subpath)
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# Check that the request (mainly the user) is permitted to access
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if not view.authorize(req):
146
# Indicate the forbidden object if this is an admin.
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if req.user and req.user.admin:
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raise Unauthorized('Unauthorized: %s' % view)
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# Non-GET requests from other sites leave us vulnerable to
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referer = req.headers_in.get('Referer')
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if (referer is None or
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urlparse.urlparse(req.headers_in.get('Referer')).netloc !=
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if req.method != 'GET' and not view.offsite_posts_allowed:
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"Non-GET requests from external sites are forbidden "
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"for security reasons.")
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# Render the output
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except HTTPError, e:
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if hasattr(viewcls, 'get_error_view'):
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errviewcls = viewcls.get_error_view(e)
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errviewcls = XHTMLView.get_error_view(e)
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errview = errviewcls(req, e)
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errview = errviewcls(req, e, obj)
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errview.render(req)
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req.write(e.message)
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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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except Exception, e:
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# A non-HTTPError appeared. We have an unknown exception. Panic.
186
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handle_unknown_exception(req, *sys.exc_info())
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# Commit the transaction if we have a store open.
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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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except Unauthorized, e:
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# Resolution failed due to a permission check. Display a pretty
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# error, or maybe a login page.
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XHTMLView.get_error_view(e)(req, e, req.publisher.root).render(req)
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# app is the App object for the chosen app
212
app = ivle.conf.apps.app_url[ivle.conf.apps.default_app]
214
app = ivle.conf.apps.app_url[req.app]
216
# 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.
220
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:
202
except PublishingError, e:
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if req.user and req.user.admin:
206
XHTMLErrorView(req, NotFound('Not found: ' +
207
str(e.args)), e[0]).render(req)
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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.
262
# Use req.throw_error to do that.
209
XHTMLErrorView(req, NotFound(), e[0]).render(req)
213
# Make sure we close the store.
265
216
def handle_unknown_exception(req, exc_type, exc_value, exc_traceback):
321
logging.debug('Logging Unhandled Exception')
323
# We handle 3 types of error.
324
# IVLEErrors with 4xx response codes (client error).
325
# IVLEErrors with 5xx response codes (handled server error).
326
# Other exceptions (unhandled server error).
327
# IVLEErrors should not have other response codes than 4xx or 5xx
328
# (eg. throw_redirect should have been used for 3xx codes).
329
# Therefore, that is treated as an unhandled error.
331
if (exc_type == util.IVLEError and httpcode >= 400
332
and httpcode <= 499):
333
# IVLEErrors with 4xx response codes are client errors.
334
# Therefore, these have a "nice" response (we even coat it in the IVLE
337
req.write_html_head_foot = True
338
req.write_javascript_settings = False
339
req.write('<div id="ivle_padding">\n')
341
codename, msg = req.get_http_codename(httpcode)
342
except AttributeError:
343
codename, msg = None, None
344
# Override the default message with the supplied one,
346
if exc_value.message is not None:
347
msg = exc_value.message
348
if codename is not None:
349
req.write("<h1>Error: %s</h1>\n" % cgi.escape(codename))
351
req.write("<h1>Error</h1>\n")
353
req.write("<p>%s</p>\n" % cgi.escape(msg))
355
req.write("<p>An unknown error occured.</p>\n")
358
logging.info(str(msg))
360
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
362
req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
363
%cgi.escape(logfile))
364
req.write('</div>\n')
365
html.write_html_foot(req)
256
# A "bad" error message. We shouldn't get here unless IVLE
257
# misbehaves (which is currently very easy, if things aren't set up
259
# Write the traceback.
261
# We need to special-case IVLEJailError, as we can get another
262
# almost-exception out of it.
263
if exc_type is util.IVLEJailError:
264
tb = 'Exception information extracted from IVLEJailError:\n'
265
tb += urllib.unquote(exc_value.info)
367
# A "bad" error message. We shouldn't get here unless IVLE
368
# misbehaves (which is currently very easy, if things aren't set up
370
# Write the traceback.
371
# If this is a non-4xx IVLEError, get the message and httpcode and
372
# make the error message a bit nicer (but still include the
374
# We also need to special-case IVLEJailError, as we can get another
375
# almost-exception out of it.
377
codename, msg = None, None
379
if exc_type is util.IVLEJailError:
380
msg = exc_value.type_str + ": " + exc_value.message
381
tb = 'Exception information extracted from IVLEJailError:\n'
382
tb += urllib.unquote(exc_value.info)
385
codename, msg = req.get_http_codename(httpcode)
386
except AttributeError:
388
# Override the default message with the supplied one,
390
if hasattr(exc_value, 'message') and exc_value.message is not None:
391
msg = exc_value.message
392
# Prepend the exception type
393
if exc_type != util.IVLEError:
394
msg = exc_type.__name__ + ": " + msg
396
tb = ''.join(traceback.format_exception(exc_type, exc_value,
400
logging.error('%s\n%s'%(str(msg), tb))
401
# Error messages are only displayed is the user is NOT a student,
402
# or if there has been a problem logging the error message
403
show_errors = (not publicmode) and ((login and \
404
str(role) != "student") or logfail)
405
req.write("""<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
267
tb = ''.join(traceback.format_exception(exc_type, exc_value,
270
logging.error('\n' + tb)
272
# Error messages are only displayed is the user is NOT a student,
273
# or if there has been a problem logging the error message
274
show_errors = (not publicmode) and ((login and req.user.admin) or logfail)
275
req.write("""<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
406
276
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
407
277
<html xmlns="http://www.w3.org/1999/xhtml">
408
278
<head><title>IVLE Internal Server Error</title></head>
410
<h1>IVLE Internal Server Error""")
412
if (codename is not None
413
and httpcode != mod_python.apache.HTTP_INTERNAL_SERVER_ERROR):
414
req.write(": %s" % cgi.escape(codename))
280
<h1>IVLE Internal Server Error</h1>
417
281
<p>An error has occured which is the fault of the IVLE developers or
418
administration. The developers have been notified.</p>
422
req.write("<p>%s</p>\n" % cgi.escape(msg))
423
if httpcode is not None:
424
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
426
<p>Please report this to <a href="mailto:%s">%s</a> (the system
427
administrator). Include the following information:</p>
428
""" % (cgi.escape(admin_email), cgi.escape(admin_email)))
430
req.write("<pre>\n%s\n</pre>\n"%cgi.escape(tb))
432
req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
433
%cgi.escape(logfile))
434
req.write("</body></html>")
285
req.write("Please report this issue to the server administrators, "
286
"along with the following information.")
288
req.write("Details have been logged for further examination.")
292
req.write("<h2>Debugging information</h2>")
293
req.write("<pre>\n%s\n</pre>\n"%cgi.escape(tb))
294
req.write("</body></html>")
added
removed
ivle/dispatch/__init__.py
