42
42
from ivle import util
44
45
from ivle.dispatch.request import Request
45
import ivle.webapp.security
46
from ivle.webapp.base.plugins import ViewPlugin, PublicViewPlugin
47
from ivle.webapp.base.xhtml import XHTMLView, XHTMLErrorView
48
from ivle.webapp.errors import BadRequest, HTTPError, NotFound, Unauthorized
49
from ivle.webapp.publisher import Publisher, PublishingError
50
from ivle.webapp import ApplicationRoot
52
config = ivle.config.Config()
54
class ObjectPermissionCheckingPublisher(Publisher):
55
"""A specialised publisher that checks object permissions.
57
This publisher verifies that the user holds any permission at all
58
on the model objects through which the resolution path passes. If
59
no permission is held, resolution is aborted with an Unauthorized
62
IMPORTANT: This does NOT check view permissions. It only checks
63
the objects in between the root and the view, exclusive!
66
def traversed_to_object(self, obj):
67
"""Check that the user has any permission at all over the object."""
68
if (hasattr(obj, 'get_permissions') and
69
len(obj.get_permissions(self.root.user, config)) == 0):
70
# Indicate the forbidden object if this is an admin.
71
if self.root.user and self.root.user.admin:
72
raise Unauthorized('Unauthorized: %s' % obj)
77
def generate_publisher(view_plugins, root, publicmode=False):
46
from ivle.dispatch import login
49
import plugins.console # XXX: Relies on www/ being in the Python path.
51
# XXX List of plugins, which will eventually be read in from conf
53
'ivle.webapp.admin.user#Plugin',
54
'ivle.webapp.browser#Plugin',
55
'ivle.webapp.groups#Plugin',
56
'ivle.webapp.tutorial#Plugin',
59
def get_routes_mapper():
79
61
Build a Mapper object for doing URL matching using 'routes', based on the
80
given plugin registry.
82
r = ObjectPermissionCheckingPublisher(root=root)
84
r.add_set_switch('api', 'api')
87
view_attr = 'public_views'
88
forward_route_attr = 'public_forward_routes'
89
reverse_route_attr = 'public_reverse_routes'
92
forward_route_attr = 'forward_routes'
93
reverse_route_attr = 'reverse_routes'
96
for plugin in view_plugins:
97
if hasattr(plugin, forward_route_attr):
98
for fr in getattr(plugin, forward_route_attr):
99
# An annotated function can also be passed in directly.
100
if hasattr(fr, '_forward_route_meta'):
101
r.add_forward_func(fr)
105
if hasattr(plugin, reverse_route_attr):
106
for rr in getattr(plugin, reverse_route_attr):
107
# An annotated function can also be passed in directly.
108
if hasattr(rr, '_reverse_route_src'):
109
r.add_reverse_func(rr)
113
if hasattr(plugin, view_attr):
114
for v in getattr(plugin, view_attr):
119
def handler(apachereq):
120
"""Handles an HTTP request.
64
m = routes.Mapper(explicit=True)
65
for pluginstr in plugins_HACK:
66
plugin_path, classname = pluginstr.split('#')
67
# Load the plugin module from somewhere in the Python path
68
# (Note that plugin_path is a fully-qualified Python module name).
69
plugin = getattr(__import__(plugin_path, fromlist=[classname]),
71
# Establish a URL pattern for each element of plugin.urls
72
for url in plugin.urls:
75
kwargs_dict = url[2] if len(url) >= 3 else {}
76
m.connect(routex, view=view_class, **kwargs_dict)
80
"""Handles a request which may be to anywhere in the site except media.
122
81
Intended to be called by mod_python, as a handler.
124
@param apachereq: An Apache request object.
126
# Make the request object into an IVLE request which can be given to views
127
req = Request(apachereq, config)
129
req.publisher = generate_publisher(
130
config.plugin_index[ViewPlugin], ApplicationRoot(req),
131
publicmode=req.publicmode)
134
obj, viewcls, subpath = req.publisher.resolve(req.uri.decode('utf-8'))
136
# We 404 if we have a subpath but the view forbids it.
137
if not viewcls.subpath_allowed and subpath:
140
# Instantiate the view, which should be a BaseView class
141
view = viewcls(req, obj, subpath)
143
# Check that the request (mainly the user) is permitted to access
145
if not view.authorize(req):
146
# Indicate the forbidden object if this is an admin.
147
if req.user and req.user.admin:
148
raise Unauthorized('Unauthorized: %s' % view)
152
# Non-GET requests from other sites leave us vulnerable to
154
referer = req.headers_in.get('Referer')
155
if (referer is None or
156
urlparse.urlparse(req.headers_in.get('Referer')).netloc !=
158
if req.method != 'GET' and not view.offsite_posts_allowed:
160
"Non-GET requests from external sites are forbidden "
161
"for security reasons.")
166
# A view explicitly raised an HTTP error. Respect it.
169
# Try to find a custom error view.
170
if hasattr(viewcls, 'get_error_view'):
171
errviewcls = viewcls.get_error_view(e)
173
errviewcls = XHTMLView.get_error_view(e)
176
errview = errviewcls(req, e, obj)
184
except mod_python.apache.SERVER_RETURN:
185
# A mod_python-specific Apache error.
186
# XXX: We need to raise these because req.throw_error() uses them.
187
# Remove this after Google Code issue 117 is fixed.
190
# A non-HTTPError appeared. We have an unknown exception. Panic.
191
handle_unknown_exception(req, *sys.exc_info())
194
# Commit the transaction if we have a store open.
197
except Unauthorized, e:
198
# Resolution failed due to a permission check. Display a pretty
199
# error, or maybe a login page.
200
XHTMLView.get_error_view(e)(req, e, req.publisher.root).render(req)
202
except PublishingError, e:
205
if req.user and req.user.admin:
206
XHTMLErrorView(req, NotFound('Not found: ' +
207
str(e.args)), e[0]).render(req)
209
XHTMLErrorView(req, NotFound(), e[0]).render(req)
213
# Make sure we close the store.
83
req: An Apache request object.
85
# Make the request object into an IVLE request which can be passed to apps
88
req = Request(req, html.write_html_head)
90
# Pass the apachereq to error reporter, since ivle req isn't created
92
handle_unknown_exception(apachereq, *sys.exc_info())
93
# Tell Apache not to generate its own errors as well
94
return mod_python.apache.OK
96
# Run the main handler, and catch all exceptions
98
return handler_(req, apachereq)
99
except mod_python.apache.SERVER_RETURN:
100
# An apache error. We discourage these, but they might still happen.
104
handle_unknown_exception(req, *sys.exc_info())
105
# Tell Apache not to generate its own errors as well
106
return mod_python.apache.OK
108
def handler_(req, apachereq):
110
Nested handler function. May raise exceptions. The top-level handler is
111
just used to catch exceptions.
112
Takes both an IVLE request and an Apache req.
114
# Hack? Try and get the user login early just in case we throw an error
115
# (most likely 404) to stop us seeing not logged in even when we are.
116
if not req.publicmode:
117
req.user = login.get_user_details(req)
119
### BEGIN New plugins framework ###
120
# XXX This should be done ONCE per Python process, not per request.
122
# XXX No authentication is done here
123
req.mapper = get_routes_mapper()
124
matchdict = req.mapper.match(req.uri)
125
if matchdict is not None:
126
viewcls = matchdict['view']
127
# Get the remaining arguments, less 'view', 'action' and 'controller'
128
# (The latter two seem to be built-in, and we don't want them).
129
kwargs = matchdict.copy()
131
# Instantiate the view, which should be a BaseView class
132
view = viewcls(req, **kwargs)
137
### END New plugins framework ###
139
# Check req.app to see if it is valid. 404 if not.
140
if req.app is not None and req.app not in ivle.conf.apps.app_url:
141
req.throw_error(Request.HTTP_NOT_FOUND,
142
"There is no application called %s." % repr(req.app))
144
# Special handling for public mode - only allow the public app, call it
146
# NOTE: This will not behave correctly if the public app uses
147
# write_html_head_foot, but "serve" does not.
149
if req.app != ivle.conf.apps.public_app:
150
req.throw_error(Request.HTTP_FORBIDDEN,
151
"This application is not available on the public site.")
152
app = ivle.conf.apps.app_url[ivle.conf.apps.public_app]
153
apps.call_app(app.dir, req)
156
# app is the App object for the chosen app
158
app = ivle.conf.apps.app_url[ivle.conf.apps.default_app]
160
app = ivle.conf.apps.app_url[req.app]
162
# Check if app requires auth. If so, perform authentication and login.
163
# This will either return a User object, None, or perform a redirect
164
# which we will not catch here.
166
req.user = login.login(req)
167
logged_in = req.user is not None
169
req.user = login.get_user_details(req)
173
# Keep the user's session alive by writing to the session object.
174
# req.get_session().save()
175
# Well, it's a fine idea, but it creates considerable grief in the
176
# concurrent update department, so instead, we'll just make the
177
# sessions not time out.
178
req.get_session().unlock()
180
# If user did not specify an app, HTTP redirect to default app and
183
req.throw_redirect(util.make_path(ivle.conf.apps.default_app))
185
# Set the default title to the app's tab name, if any. Otherwise URL
187
if app.name is not None:
192
# Call the specified app with the request object
193
apps.call_app(app.dir, req)
195
# if not logged in, login.login will have written the login box.
196
# Just clean up and exit.
198
# MAKE SURE we write the HTTP (and possibly HTML) header. This
199
# wouldn't happen if nothing else ever got written, so we have to make
201
req.ensure_headers_written()
203
# When done, write out the HTML footer if the app has requested it
204
if req.write_html_head_foot:
205
# Show the console if required
206
if logged_in and app.useconsole:
207
plugins.console.present(req, windowpane=True)
208
html.write_html_foot(req)
210
# Note: Apache will not write custom HTML error messages here.
211
# Use req.throw_error to do that.
216
214
def handle_unknown_exception(req, exc_type, exc_value, exc_traceback):
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)
270
logging.debug('Logging Unhandled Exception')
272
# We handle 3 types of error.
273
# IVLEErrors with 4xx response codes (client error).
274
# IVLEErrors with 5xx response codes (handled server error).
275
# Other exceptions (unhandled server error).
276
# IVLEErrors should not have other response codes than 4xx or 5xx
277
# (eg. throw_redirect should have been used for 3xx codes).
278
# Therefore, that is treated as an unhandled error.
280
if (exc_type == util.IVLEError and httpcode >= 400
281
and httpcode <= 499):
282
# IVLEErrors with 4xx response codes are client errors.
283
# Therefore, these have a "nice" response (we even coat it in the IVLE
286
req.write_html_head_foot = True
287
req.write_javascript_settings = False
288
req.write('<div id="ivle_padding">\n')
290
codename, msg = req.get_http_codename(httpcode)
291
except AttributeError:
292
codename, msg = None, None
293
# Override the default message with the supplied one,
295
if exc_value.message is not None:
296
msg = exc_value.message
297
if codename is not None:
298
req.write("<h1>Error: %s</h1>\n" % cgi.escape(codename))
300
req.write("<h1>Error</h1>\n")
302
req.write("<p>%s</p>\n" % cgi.escape(msg))
304
req.write("<p>An unknown error occured.</p>\n")
307
logging.info(str(msg))
309
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
311
req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
312
%cgi.escape(logfile))
313
req.write('</div>\n')
314
html.write_html_foot(req)
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"
316
# A "bad" error message. We shouldn't get here unless IVLE
317
# misbehaves (which is currently very easy, if things aren't set up
319
# Write the traceback.
320
# If this is a non-4xx IVLEError, get the message and httpcode and
321
# make the error message a bit nicer (but still include the
323
# We also need to special-case IVLEJailError, as we can get another
324
# almost-exception out of it.
326
codename, msg = None, None
328
if exc_type is util.IVLEJailError:
329
msg = exc_value.type_str + ": " + exc_value.message
330
tb = 'Exception information extracted from IVLEJailError:\n'
331
tb += urllib.unquote(exc_value.info)
334
codename, msg = req.get_http_codename(httpcode)
335
except AttributeError:
337
# Override the default message with the supplied one,
339
if hasattr(exc_value, 'message') and exc_value.message is not None:
340
msg = exc_value.message
341
# Prepend the exception type
342
if exc_type != util.IVLEError:
343
msg = exc_type.__name__ + ": " + msg
345
tb = ''.join(traceback.format_exception(exc_type, exc_value,
349
logging.error('%s\n%s'%(str(msg), tb))
350
# Error messages are only displayed is the user is NOT a student,
351
# or if there has been a problem logging the error message
352
show_errors = (not publicmode) and ((login and \
353
str(role) != "student") or logfail)
354
req.write("""<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
276
355
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
277
356
<html xmlns="http://www.w3.org/1999/xhtml">
278
357
<head><title>IVLE Internal Server Error</title></head>
280
<h1>IVLE Internal Server Error</h1>
359
<h1>IVLE Internal Server Error""")
361
if (codename is not None
362
and httpcode != mod_python.apache.HTTP_INTERNAL_SERVER_ERROR):
363
req.write(": %s" % cgi.escape(codename))
281
366
<p>An error has occured which is the fault of the IVLE developers or
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>")
367
administration. The developers have been notified.</p>
371
req.write("<p>%s</p>\n" % cgi.escape(msg))
372
if httpcode is not None:
373
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
375
<p>Please report this to <a href="mailto:%s">%s</a> (the system
376
administrator). Include the following information:</p>
377
""" % (cgi.escape(admin_email), cgi.escape(admin_email)))
379
req.write("<pre>\n%s\n</pre>\n"%cgi.escape(tb))
381
req.write("<p>Warning: Could not open Error Log: '%s'</p>\n"
382
%cgi.escape(logfile))
383
req.write("</body></html>")