1
# IVLE - Informatics Virtual Learning Environment
2
# Copyright (C) 2007-2009 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
18
# Author: Matt Giuca, Will Grant
25
import genshi.template
29
from ivle.webapp.errors import BadRequest, MethodNotAllowed
31
class BaseView(object):
33
Abstract base class for all view objects.
35
def __init__(self, req, **kwargs):
37
def render(self, req):
40
class RESTView(BaseView):
42
A view which provides a RESTful interface. The content type is
43
unspecified (see JSONRESTView for a specific content type).
45
content_type = "application/octet-stream"
47
def __init__(self, req, *args, **kwargs):
50
def render(self, req):
51
if req.method == 'GET':
52
outstr = self.GET(req)
54
if req.method == 'PUT':
55
outstr = self.PATCH(req, req.read())
56
req.content_type = self.content_type
59
class JSONRESTView(RESTView):
61
A special case of RESTView which deals entirely in JSON.
63
content_type = "application/json"
65
_allowed_methods = property(
66
lambda self: [m for m in ('GET', 'PUT', 'PATCH')
67
if hasattr(self, m)] + ['POST'])
69
def render(self, req):
70
if req.method not in self._allowed_methods:
71
raise MethodNotAllowed(allowed=self._allowed_methods)
73
if req.method == 'GET':
74
outjson = self.GET(req)
75
# Since PATCH isn't yet an official HTTP method, we allow users to
76
# turn a PUT into a PATCH by supplying a special header.
77
elif req.method == 'PATCH' or (req.method == 'PUT' and
78
'X-IVLE-Patch-Semantics' in req.headers_in and
79
req.headers_in['X-IVLE-Patch-Semantics'].lower() == 'yes'):
80
outjson = self.PATCH(req, cjson.decode(req.read()))
81
elif req.method == 'PUT':
82
outjson = self.PUT(req, cjson.decode(req.read()))
83
# POST implies named operation.
84
elif req.method == 'POST':
85
# TODO: Check Content-Type and implement multipart/form-data.
86
opargs = dict(cgi.parse_qsl(req.read()))
88
opname = opargs['ivle.op']
91
raise BadRequest('No named operation specified.')
94
op = getattr(self, opname)
95
except AttributeError:
96
raise BadRequest('Invalid named operation.')
98
if not hasattr(op, '_rest_api_callable') or \
99
not op._rest_api_callable:
100
raise BadRequest('Invalid named operation.')
102
# Find any missing arguments, except for the first two (self, req)
103
(args, vaargs, varkw, defaults) = inspect.getargspec(op)
106
# To find missing arguments, we eliminate the provided arguments
107
# from the set of remaining function signature arguments. If the
108
# remaining signature arguments are in the args[-len(defaults):],
110
unspec = set(args) - set(opargs.keys())
111
if unspec and not defaults:
112
raise BadRequest('Missing arguments: ' + ','.join(unspec))
114
unspec = [k for k in unspec if k not in args[-len(defaults):]]
117
raise BadRequest('Missing arguments: ' + ','.join(unspec))
119
# We have extra arguments if the are no match args in the function
120
# signature, AND there is no **.
121
extra = set(opargs.keys()) - set(args)
122
if extra and not varkw:
123
raise BadRequest('Extra arguments: ' + ', '.join(extra))
125
outjson = op(req, **opargs)
127
raise AssertionError('Unknown method somehow got through.')
129
req.content_type = self.content_type
130
if outjson is not None:
131
req.write(cjson.encode(outjson))
134
def named_operation(meth):
135
'''Declare a function to be accessible to HTTP users via the REST API.
137
meth._rest_api_callable = True
140
class XHTMLView(BaseView):
142
A view which provides a base class for views which need to return XHTML
143
It is expected that apps which use this view will be written using Genshi
146
def __init__(self, req, **kwargs):
148
setattr(self, key, kwargs[key])
150
def render(self, req):
151
req.content_type = 'text/html' # TODO: Detect application/xhtml+xml
152
ctx = genshi.template.Context()
153
self.populate(req, ctx)
154
self.populate_headings(req, ctx)
156
ctx['app_styles'] = req.styles
157
ctx['scripts'] = req.scripts
158
ctx['scripts_init'] = req.scripts_init
159
app_template = os.path.join(os.path.dirname(
160
inspect.getmodule(self).__file__), self.app_template)
161
req.write_html_head_foot = False
162
loader = genshi.template.TemplateLoader(".", auto_reload=True)
163
tmpl = loader.load(app_template)
164
app = tmpl.generate(ctx)
165
ctx['app_template'] = app
166
tmpl = loader.load(os.path.join(os.path.dirname(__file__),
167
'ivle-headings.html'))
168
req.write(tmpl.generate(ctx).render('xhtml', doctype='xhtml'))
170
def populate_headings(self, req, ctx):
171
ctx['favicon'] = None
172
ctx['root_dir'] = ivle.conf.root_dir
173
ctx['public_host'] = ivle.conf.public_host
174
ctx['write_javascript_settings'] = req.write_javascript_settings
176
ctx['login'] = req.user.login
177
ctx['logged_in'] = True
178
ctx['nick'] = req.user.nick
181
ctx['publicmode'] = req.publicmode
182
ctx['apps_in_tabs'] = []
183
for urlname in ivle.conf.apps.apps_in_tabs:
185
app = ivle.conf.apps.app_url[urlname]
186
new_app['this_app'] = urlname == self.appname
188
new_app['has_icon'] = True
189
icon_dir = ivle.conf.apps.app_icon_dir
190
icon_url = ivle.util.make_path(os.path.join(icon_dir, app.icon))
191
new_app['icon_url'] = icon_url
192
if new_app['this_app']:
193
ctx['favicon'] = icon_url
195
new_app['has_icon'] = False
196
new_app['path'] = ivle.util.make_path(urlname)
197
new_app['desc'] = app.desc
198
new_app['name'] = app.name
199
ctx['apps_in_tabs'].append(new_app)