2
# Copyright (C) 2007-2008 The University of Melbourne
4
# This program is free software; you can redistribute it and/or modify
5
# it under the terms of the GNU General Public License as published by
6
# the Free Software Foundation; either version 2 of the License, or
7
# (at your option) any later version.
9
# This program is distributed in the hope that it will be useful,
10
# but WITHOUT ANY WARRANTY; without even the implied warranty of
11
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12
# GNU General Public License for more details.
14
# You should have received a copy of the GNU General Public License
15
# along with this program; if not, write to the Free Software
16
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22
# This is a mod_python handler program. The correct way to call it is to have
23
# Apache send all requests to be handled by the module 'dispatch'.
25
# Top-level handler. Handles all requests to all pages in IVLE.
26
# Handles authentication (not authorization).
27
# Then passes the request along to the appropriate ivle app.
30
from mod_python import apache
39
from request import Request
42
from common import (util, forumutil)
47
"""Handles a request which may be to anywhere in the site except media.
48
Intended to be called by mod_python, as a handler.
50
req: An Apache request object.
52
# Make the request object into an IVLE request which can be passed to apps
55
req = Request(req, html.write_html_head)
57
# Pass the apachereq to error reporter, since ivle req isn't created
59
handle_unknown_exception(apachereq, *sys.exc_info())
60
# Tell Apache not to generate its own errors as well
63
# Run the main handler, and catch all exceptions
65
return handler_(req, apachereq)
66
except mod_python.apache.SERVER_RETURN:
67
# An apache error. We discourage these, but they might still happen.
71
handle_unknown_exception(req, *sys.exc_info())
72
# Tell Apache not to generate its own errors as well
75
def handler_(req, apachereq):
77
Nested handler function. May raise exceptions. The top-level handler is
78
just used to catch exceptions.
79
Takes both an IVLE request and an Apache req.
81
# Check req.app to see if it is valid. 404 if not.
82
if req.app is not None and req.app not in conf.apps.app_url:
83
# Maybe it is a special app!
84
if req.app == 'logout':
87
req.throw_error(Request.HTTP_NOT_FOUND,
88
"There is no application called %s." % repr(req.app))
90
# Special handling for public mode - just call public app and get out
91
# NOTE: This will not behave correctly if the public app uses
92
# write_html_head_foot, but "serve" does not.
94
app = conf.apps.app_url[conf.apps.public_app]
95
apps.call_app(app.dir, req)
98
# app is the App object for the chosen app
100
app = conf.apps.app_url[conf.apps.default_app]
102
app = conf.apps.app_url[req.app]
104
# Check if app requires auth. If so, perform authentication and login.
105
# This will either return a User object, None, or perform a redirect
106
# which we will not catch here.
108
req.user = login.login(req)
109
logged_in = req.user is not None
111
req.user = login.get_user_details(req)
115
# Keep the user's session alive by writing to the session object.
116
# req.get_session().save()
117
# Well, it's a fine idea, but it creates considerable grief in the
118
# concurrent update department, so instead, we'll just make the
119
# sessions not time out.
121
# If user did not specify an app, HTTP redirect to default app and
124
req.throw_redirect(util.make_path(conf.apps.default_app))
126
# Set the default title to the app's tab name, if any. Otherwise URL
128
if app.name is not None:
133
# Call the specified app with the request object
134
apps.call_app(app.dir, req)
136
# if not logged in, login.login will have written the login box.
137
# Just clean up and exit.
139
# MAKE SURE we write the HTTP (and possibly HTML) header. This
140
# wouldn't happen if nothing else ever got written, so we have to make
142
req.ensure_headers_written()
144
# When done, write out the HTML footer if the app has requested it
145
if req.write_html_head_foot:
146
html.write_html_foot(req)
148
# Note: Apache will not write custom HTML error messages here.
149
# Use req.throw_error to do that.
153
"""Log out the current user (if any) by destroying the session state.
154
Then redirect to the top-level IVLE page."""
155
session = req.get_session()
158
req.add_cookie(forumutil.invalidated_forum_cookie())
159
req.throw_redirect(util.make_path(''))
161
def handle_unknown_exception(req, exc_type, exc_value, exc_traceback):
163
Given an exception that has just been thrown from IVLE, print its details
165
This is a full handler. It assumes nothing has been written, and writes a
167
req: May be EITHER an IVLE req or an Apache req.
168
IVLE reqs may have the HTML head/foot written (on a 400 error), but
169
the handler code may pass an apache req if an exception occurs before
170
the IVLE request is created.
172
req.content_type = "text/html"
173
# For some reason, some versions of mod_python have "_server" instead of
174
# "main_server". So we check for both.
176
admin_email = apache.main_server.server_admin
177
except AttributeError:
179
admin_email = apache._server.server_admin
180
except AttributeError:
183
httpcode = exc_value.httpcode
184
req.status = httpcode
185
except AttributeError:
187
req.status = apache.HTTP_INTERNAL_SERVER_ERROR
188
# We handle 3 types of error.
189
# IVLEErrors with 4xx response codes (client error).
190
# IVLEErrors with 5xx response codes (handled server error).
191
# Other exceptions (unhandled server error).
192
# IVLEErrors should not have other response codes than 4xx or 5xx
193
# (eg. throw_redirect should have been used for 3xx codes).
194
# Therefore, that is treated as an unhandled error.
196
if (exc_type == util.IVLEError and httpcode >= 400
197
and httpcode <= 499):
198
# IVLEErrors with 4xx response codes are client errors.
199
# Therefore, these have a "nice" response (we even coat it in the IVLE
201
req.write_html_head_foot = True
202
req.write('<div id="ivle_padding">\n')
204
codename, msg = req.get_http_codename(httpcode)
205
except AttributeError:
206
codename, msg = None, None
207
# Override the default message with the supplied one,
209
if exc_value.message is not None:
210
msg = exc_value.message
211
if codename is not None:
212
req.write("<h1>Error: %s</h1>\n" % codename)
214
req.write("<h1>Error</h1>\n")
216
req.write("<p>%s</p>\n" % msg)
218
req.write("<p>An unknown error occured.</p>\n")
219
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
220
req.write('</div>\n')
222
# A "bad" error message. We shouldn't get here unless IVLE
223
# misbehaves (which is currently very easy, if things aren't set up
225
# Write the traceback.
226
# If this is a non-4xx IVLEError, get the message and httpcode and
227
# make the error message a bit nicer (but still include the
230
codename, msg = req.get_http_codename(httpcode)
231
except AttributeError:
232
codename, msg = None, None
233
# Override the default message with the supplied one,
235
if hasattr(exc_value, 'message') and exc_value.message is not None:
236
msg = exc_value.message
239
<head><title>IVLE Internal Server Error</title></head>
241
<h1>IVLE Internal Server Error""")
242
if (codename is not None
243
and httpcode != apache.HTTP_INTERNAL_SERVER_ERROR):
244
req.write(": %s" % codename)
246
<p>An error has occured which is the fault of the IVLE developers or
250
req.write("<p>%s</p>\n" % msg)
251
if httpcode is not None:
252
req.write("<p>(HTTP error code %d)</p>\n" % httpcode)
254
<p>Please report this to <a href="mailto:%s">%s</a> (the system
255
administrator). Include the following information:</p>
256
""" % (admin_email, admin_email))
258
tb_print = cStringIO.StringIO()
259
traceback.print_exception(exc_type, exc_value, exc_traceback,
262
req.write(tb_print.getvalue())
263
req.write("</pre>\n</body>\n")