1
# IVLE - Informatics Virtual Learning Environment
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
# Contains common utility functions.
23
# Also initialises mime types library. You must import util before using
24
# Python's builtin mimetypes module to make sure local settings are applied.
31
import ivle.conf.mimetypes
33
class IVLEError(Exception):
35
This is the "standard" exception class for IVLE errors.
36
It is the ONLY exception which should propagate to the top - it will then
37
be displayed to the user as an HTTP error with the given code.
39
All other exceptions are considered IVLE bugs and should not occur
40
(they will display a traceback).
42
This error should not be raised directly. Call req.throw_error.
44
def __init__(self, httpcode, message=None):
45
self.httpcode = httpcode
46
self.message = message
47
self.args = (httpcode, message)
49
class IVLEJailError(Exception):
51
This exception indicates an error that occurred inside an IVLE CGI script
52
inside the jail. It should never be raised directly - only by the
55
Information will be retrieved from it, and then treated as a normal
58
def __init__(self, type_str, message, info):
59
self.type_str = type_str
60
self.message = message
63
class FakeObject(object):
64
""" A representation of an object that can't be Pickled """
65
def __init__(self, type, name, attrib={}):
71
return "<Fake %s %s>"%(self.type, self.name)
75
"""Given a path relative to the IVLE root, makes the path relative to the
76
site root using ivle.conf.root_dir. This path can be used in URLs sent to
78
return os.path.join(ivle.conf.root_dir, path)
80
def make_local_path(path):
81
"""Given a path relative to the IVLE root, on the local file system, makes
82
the path relative to the root using ivle.conf.share_path. This path can
83
be used in reading files from the local file system."""
84
return os.path.join(ivle.conf.share_path, 'www', path)
86
def unmake_path(path):
87
"""Given a path relative to the site root, makes the path relative to the
88
IVLE root by removing ivle.conf.root_dir if it appears at the beginning. If
89
it does not appear at the beginning, returns path unchanged. Also
90
normalises the path."""
91
path = os.path.normpath(path)
92
root = os.path.normpath(ivle.conf.root_dir)
94
if path.startswith(root):
95
path = path[len(root):]
96
# Take out the slash as well
97
if len(path) > 0 and path[0] == os.sep:
102
def split_path(path):
103
"""Given a path, returns a tuple consisting of the top-level directory in
104
the path, and the rest of the path. Note that both items in the tuple will
105
NOT begin with a slash, regardless of whether the original path did. Also
108
Always returns a pair of strings, except for one special case, in which
109
the path is completely empty (or just a single slash). In this case the
110
return value will be (None, ''). But still always returns a pair.
118
>>> split_path("home")
120
>>> split_path("home/docs/files")
121
('home', 'docs/files')
122
>>> split_path("//home/docs/files")
123
('', 'home/docs/files')
125
path = os.path.normpath(path)
126
# Ignore the opening slash
127
if path.startswith(os.sep):
128
path = path[len(os.sep):]
129
if path == '' or path == '.':
131
splitpath = path.split(os.sep, 1)
132
if len(splitpath) == 1:
133
return (splitpath[0], '')
135
return tuple(splitpath)
137
def open_exercise_file(exercisename):
138
"""Given an exercise name, opens the corresponding XML file for reading.
139
Returns None if the exercise file was not found.
140
(For tutorials / worksheets).
142
# First normalise the path
143
exercisename = os.path.normpath(exercisename)
144
# Now if it begins with ".." or separator, then it's illegal
145
if exercisename.startswith("..") or exercisename.startswith(os.sep):
148
exercisefile = os.path.join(ivle.conf.exercises_base, exercisename)
151
return open(exercisefile)
152
except (TypeError, IOError): # TypeError if exercisefile == None
155
# Initialise mime types library
157
for (ext, mimetype) in ivle.conf.mimetypes.additional_mime_types.items():
158
mimetypes.add_type(mimetype, ext)
160
def nice_filetype(filename):
161
"""Given a filename or basename, returns a "friendly" name for that
163
eg. nice_mimetype("file.py") == "Python source code".
164
nice_filetype("file.bzg") == "BZG file".
165
nice_filetype("directory/") == "Directory".
167
if filename[-1] == os.sep:
171
return ivle.conf.mimetypes.nice_mimetypes[
172
mimetypes.guess_type(filename)[0]]
174
filename = os.path.basename(filename)
176
return filename[filename.rindex('.')+1:].upper() + " file"
180
def get_terms_of_service():
182
Sends the Terms of Service document to the req object.
183
This consults conf to find out where the TOS is located on disk, and sends
184
that. If it isn't found, it sends a generic message explaining to admins
185
how to create a real one.
188
return open(ivle.conf.tos_path).read()
190
return """<h1>Terms of Service</h1>
191
<p><b>*** SAMPLE ONLY ***</b></p>
192
<p>This is the text of the IVLE Terms of Service.</p>
193
<p>The administrator should create a license file with an appropriate
194
"Terms of Service" license for your organisation.</p>
195
<h2>Instructions for Administrators</h2>
196
<p>You are seeing this message because you have not configured a Terms of
197
Service document.</p>
198
<p>When you configured IVLE, you specified a path to the Terms of Service
199
document (this is found in <b><tt>ivle/conf/conf.py</tt></b> under
200
"<tt>tos_path</tt>").</p>
201
<p>Create a file at this location; an HTML file with the appropriately-worded
203
<p>This should be a normal XHTML file, except it should not contain
204
<tt>html</tt>, <tt>head</tt> or <tt>body</tt> elements - it should
205
just be the contents of a body element (IVLE will wrap it accordingly).</p>
206
<p>This will automatically be used as the license text instead of this
207
placeholder text.</p>
210
def parse_iso8601(str):
211
"""Parses ISO8601 string into a datetime object."""
212
# FIXME: Terrific hack that means we only accept the format that is
213
# produced by json.js module when it encodes date objects.
214
return datetime.datetime.strptime(str, "%Y-%m-%dT%H:%M:%SZ")
216
def incomplete_utf8_sequence(byteseq):
219
Given a UTF-8-encoded byte sequence (str), returns the number of bytes at
220
the end of the string which comprise an incomplete UTF-8 character
223
If the string is empty or ends with a complete character OR INVALID
225
Otherwise, returns 1-3 indicating the number of bytes in the final
226
incomplete (but valid) character sequence.
228
Does not check any bytes before the final sequence for correctness.
230
>>> incomplete_utf8_sequence("")
232
>>> incomplete_utf8_sequence("xy")
234
>>> incomplete_utf8_sequence("xy\xc3\xbc")
236
>>> incomplete_utf8_sequence("\xc3")
238
>>> incomplete_utf8_sequence("\xbc\xc3")
240
>>> incomplete_utf8_sequence("xy\xbc\xc3")
242
>>> incomplete_utf8_sequence("xy\xe0\xa0")
244
>>> incomplete_utf8_sequence("xy\xf4")
246
>>> incomplete_utf8_sequence("xy\xf4\x8f")
248
>>> incomplete_utf8_sequence("xy\xf4\x8f\xa0")
253
for b in byteseq[::-1]:
257
# 0xxxxxxx (single-byte character)
260
elif b & 0xc0 == 0x80:
261
# 10xxxxxx (subsequent byte)
263
elif b & 0xe0 == 0xc0:
264
# 110xxxxx (start of 2-byte sequence)
267
elif b & 0xf0 == 0xe0:
268
# 1110xxxx (start of 3-byte sequence)
271
elif b & 0xf8 == 0xf0:
272
# 11110xxx (start of 4-byte sequence)
280
# Seen too many "subsequent bytes", invalid
284
# We never saw a "first byte", invalid
287
# We now know expect and count
289
# Complete, or we saw an invalid sequence
295
def object_to_dict(attrnames, obj):
297
Convert an object into a dictionary. This takes a shallow copy of the
299
attrnames: Set (or iterable) of names of attributes to be copied into the
300
dictionary. (We don't auto-lookup, because this function needs to be
301
used on magical objects).
303
return dict((k, getattr(obj, k))
304
for k in attrnames if not k.startswith('_'))
added
removed
ivle/util.py
