-
Notifications
You must be signed in to change notification settings - Fork 0
/
sessions.py
502 lines (439 loc) · 17.9 KB
/
sessions.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
"""
Copyright (c) 2008, appengine-utilities project
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
- Neither the name of the appengine-utilities project nor the names of its
contributors may be used to endorse or promote products derived from this
software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""
# main python imports
import os
import time
import datetime
import random
import sha
import Cookie
import pickle
import __main__
# google appengine imports
from google.appengine.ext import db
from google.appengine.api import memcache
#django simplejson import, used for flash
from django.utils import simplejson
# settings, if you have these set elsewhere, such as your django settings file,
# you'll need to adjust the values to pull from there.
COOKIE_NAME = 'appengine-utilities-session-sid'
DEFAULT_COOKIE_PATH = '/'
SESSION_EXPIRE_TIME = 7200 # sessions are valid for 7200 seconds (2 hours)
CLEAN_CHECK_PERCENT = 15 # 15% of all requests will clean the database
INTEGRATE_FLASH = False # integrate functionality from flash module?
CHECK_IP = True # validate sessions by IP
CHECK_USER_AGENT = True # validate sessions by user agent
SET_COOKIE_EXPIRES = True # Set to True to add expiration field to cookie
SESSION_TOKEN_TTL = 5 # Number of seconds a session token is valid for.
class _AppEngineUtilities_Session(db.Model):
"""
Model for the sessions in the datastore. This contains the identifier and
validation information for the session.
"""
sid = db.StringListProperty()
ip = db.StringProperty()
ua = db.StringProperty()
last_activity = db.DateTimeProperty(auto_now=True)
class _AppEngineUtilities_SessionData(db.Model):
"""
Model for the session data in the datastore.
"""
session = db.ReferenceProperty(_AppEngineUtilities_Session)
keyname = db.StringProperty()
content = db.BlobProperty()
class Session(object):
"""
Sessions used to maintain user presence between requests.
Sessions store a unique id as a cookie in the browser and
referenced in a datastore object. This maintains user presence
by validating requests as visits from the same browser.
You can add extra data to the session object by using it
as a dictionary object. Values can be any python object that
can be pickled.
For extra performance, session objects are also store in
memcache and kept consistent with the datastore. This
increases the performance of read requests to session
data.
"""
def __init__(self, cookie_path=DEFAULT_COOKIE_PATH,
cookie_name=COOKIE_NAME, session_expire_time=SESSION_EXPIRE_TIME,
clean_check_percent=CLEAN_CHECK_PERCENT,
integrate_flash=INTEGRATE_FLASH, check_ip=CHECK_IP,
check_user_agent=CHECK_USER_AGENT,
set_cookie_expires=SET_COOKIE_EXPIRES,
session_token_ttl=SESSION_TOKEN_TTL):
"""
Initializer
Args:
cookie_name: The name for the session cookie stored in the browser.
session_expire_time: The amount of time between requests before the
session expires.
clean_check_percent: The percentage of requests the will fire off a
cleaning routine that deletes stale session data.
integrate_flash: If appengine-utilities flash utility should be
integrated into the session object.
check_ip: If browser IP should be used for session validation
check_user_agent: If the browser user agent should be used for
sessoin validation.
set_cookie_expires: True adds an expires field to the cookie so
it saves even if the browser is closed.
session_token_ttl: Number of sessions a session token is valid
for before it should be regenerated.
"""
self.cookie_path = cookie_path
self.cookie_name = cookie_name
self.session_expire_time = session_expire_time
self.clean_check_percent = clean_check_percent
self.integrate_flash = integrate_flash
self.check_user_agent = check_user_agent
self.check_ip = check_ip
self.set_cookie_expires = set_cookie_expires
self.session_token_ttl = session_token_ttl
"""
Check the cookie and, if necessary, create a new one.
"""
self.cache = {}
self.sid = None
string_cookie = os.environ.get('HTTP_COOKIE', '')
self.cookie = Cookie.SimpleCookie()
self.cookie.load(string_cookie)
# check for existing cookie
if self.cookie.get(cookie_name):
self.sid = self.cookie[cookie_name].value
# If there isn't a valid session for the cookie sid,
# start a new session.
self.session = self._get_session()
if self.session is None:
self.sid = self.new_sid()
self.session = _AppEngineUtilities_Session()
if 'HTTP_USER_AGENT' in os.environ:
self.session.ua = os.environ['HTTP_USER_AGENT']
else:
self.session.ua = None
if 'REMOTE_ADDR' in os.environ:
self.session.ip = os.environ['REMOTE_ADDR']
else:
self.session.ip = None
self.session.sid = [self.sid]
self.cookie[cookie_name] = self.sid
self.cookie[cookie_name]['path'] = cookie_path
if set_cookie_expires:
self.cookie[cookie_name]['expires'] = \
self.session_expire_time
else:
# check the age of the token to determine if a new one
# is required
duration = datetime.timedelta(seconds=self.session_token_ttl)
session_age_limit = datetime.datetime.now() - duration
if self.session.last_activity < session_age_limit:
self.sid = self.new_sid()
if len(self.session.sid) > 2:
self.session.sid.remove(self.session.sid[0])
self.session.sid.append(self.sid)
else:
self.sid = self.session.sid[-1]
self.cookie[cookie_name] = self.sid
self.cookie[cookie_name]['path'] = cookie_path
if set_cookie_expires:
self.cookie[cookie_name]['expires'] = \
self.session_expire_time
else:
self.sid = self.new_sid()
self.session = _AppEngineUtilities_Session()
self.session.ua = os.environ['HTTP_USER_AGENT']
self.session.ip = os.environ['REMOTE_ADDR']
self.session.sid = [self.sid]
self.cookie[cookie_name] = self.sid
self.cookie[cookie_name]['path'] = cookie_path
if set_cookie_expires:
self.cookie[cookie_name]['expires'] = self.session_expire_time
self.cache['sid'] = pickle.dumps(self.sid)
# update the last_activity field in the datastore every time that
# the session is accessed. This also handles the write for all
# session data above.
self.session.put()
print self.cookie
# fire up a Flash object if integration is enabled
if self.integrate_flash:
import flash
self.flash = flash.Flash(cookie=self.cookie)
# randomly delete old stale sessions in the datastore (see
# CLEAN_CHECK_PERCENT variable)
if random.randint(1, 100) < CLEAN_CHECK_PERCENT:
self._clean_old_sessions()
def new_sid(self):
"""
Create a new session id.
"""
sid = sha.new(repr(time.time()) + os.environ['REMOTE_ADDR'] + \
str(random.random())).hexdigest()
return sid
def _get_session(self):
"""
Get the user's session from the datastore
"""
query = _AppEngineUtilities_Session.all()
query.filter('sid', self.sid)
if self.check_user_agent:
query.filter('ua', os.environ['HTTP_USER_AGENT'])
if self.check_ip:
query.filter('ip', os.environ['REMOTE_ADDR'])
results = query.fetch(1)
if len(results) is 0:
return None
else:
sessionAge = datetime.datetime.now() - results[0].last_activity
if sessionAge.seconds > self.session_expire_time:
results[0].delete()
return None
return results[0]
def _get(self, keyname=None):
"""
Return all of the SessionData object unless keyname is specified, in
which case only that instance of SessionData is returned.
Important: This does not interact with memcache and pulls directly
from the datastore.
Args:
keyname: The keyname of the value you are trying to retrieve.
"""
query = _AppEngineUtilities_SessionData.all()
query.filter('session', self.session)
if keyname != None:
query.filter('keyname =', keyname)
results = query.fetch(1000)
if len(results) is 0:
return None
if keyname != None:
return results[0]
return results
def _validate_key(self, keyname):
"""
Validate the keyname, making sure it is set and not a reserved name.
"""
if keyname is None:
raise ValueError('You must pass a keyname for the session' + \
' data content.')
elif keyname in ('sid', 'flash'):
raise ValueError(keyname + ' is a reserved keyname.')
if type(keyname) != type([str, unicode]):
return str(keyname)
return keyname
def _put(self, keyname, value):
"""
Insert a keyname/value pair into the datastore for the session.
Args:
keyname: The keyname of the mapping.
value: The value of the mapping.
"""
keyname = self._validate_key(keyname)
if value is None:
raise ValueError('You must pass a value to put.')
sessdata = self._get(keyname=keyname)
if sessdata is None:
sessdata = _AppEngineUtilities_SessionData()
sessdata.session = self.session
sessdata.keyname = keyname
sessdata.content = pickle.dumps(value)
self.cache[keyname] = pickle.dumps(value)
sessdata.put()
self._set_memcache()
def _delete_session(self):
"""
Delete the session and all session data for the sid passed.
"""
sessiondata = self._get()
# delete from datastore
if sessiondata is not None:
for sd in sessiondata:
sd.delete()
# delete from memcache
memcache.delete('sid-'+str(self.session.key()))
# delete the session now that all items that reference it are deleted.
self.session.delete()
# if the event class has been loaded, fire off the sessionDeleted event
if 'AEU_Events' in __main__.__dict__:
__main__.AEU_Events.fire_event('sessionDelete')
def delete(self):
"""
Delete the current session and start a new one.
This is useful for when you need to get rid of all data tied to a
current session, such as when you are logging out a user.
"""
self._delete_session()
def delete_all_sessions(self):
"""
Deletes all sessions and session data from the data store and memcache.
"""
all_sessions_deleted = False
all_data_deleted = False
while not all_sessions_deleted:
query = _AppEngineUtilities_Session.all()
results = query.fetch(1000)
if len(results) is 0:
all_sessions_deleted = True
else:
for result in results:
result.delete()
while not all_data_deleted:
query = _AppEngineUtilities_SessionData.all()
results = query.fetch(1000)
if len(results) is 0:
all_data_deleted = True
else:
for result in results:
result.delete()
def _clean_old_sessions(self):
"""
Delete expired sessions from the datastore.
This is only called for CLEAN_CHECK_PERCENT percent of requests because
it could be rather intensive.
"""
duration = datetime.timedelta(seconds=self.session_expire_time)
session_age = datetime.datetime.now() - duration
query = _AppEngineUtilities_Session.all()
query.filter('last_activity <', session_age)
results = query.fetch(1000)
for result in results:
data_query = _AppEngineUtilities_SessionData.all()
query.filter('session', result)
data_results = data_query.fetch(1000)
for data_result in data_results:
data_result.delete()
memcache.delete('sid-'+str(result.key()))
result.delete()
# Implement Python container methods
def __getitem__(self, keyname):
"""
Get item from session data.
keyname: The keyname of the mapping.
"""
# flash messages don't go in the datastore
if self.integrate_flash and (keyname == 'flash'):
return self.flash.msg
if keyname in self.cache:
return pickle.loads(str(self.cache[keyname]))
mc = memcache.get('sid-'+str(self.session.key()))
if mc is not None:
if keyname in mc:
return mc[keyname]
data = self._get(keyname)
if data:
self.cache[keyname] = data.content
self._set_memcache()
return pickle.loads(data.content)
else:
raise KeyError(str(keyname))
def __setitem__(self, keyname, value):
"""
Set item in session data.
Args:
keyname: They keyname of the mapping.
value: The value of mapping.
"""
# if type(keyname) is type(''):
# flash messages don't go in the datastore
if self.integrate_flash and (keyname == 'flash'):
self.flash.msg = value
else:
keyname = self._validate_key(keyname)
self.cache[keyname] = value
self._set_memcache()
return self._put(keyname, value)
# else:
# raise TypeError('Session data objects are only accessible by' + \
# ' string keys, not numerical indexes.')
def __delitem__(self, keyname):
"""
Delete item from session data.
Args:
keyname: The keyname of the object to delete.
"""
sessdata = self._get(keyname = keyname)
if sessdata is None:
raise KeyError(str(keyname))
sessdata.delete()
if keyname in self.cache:
del self.cache[keyname]
self._set_memcache()
def __len__(self):
"""
Return size of session.
"""
# check memcache first
mc = memcache.get('sid-'+str(self.session.key()))
if mc is not None:
return len(mc)
results = self._get()
return len(results)
def __contains__(self, keyname):
"""
Check if an item is in the session data.
Args:
keyname: The keyname being searched.
"""
try:
r = self.__getitem__(keyname)
except KeyError:
return False
return True
def __iter__(self):
"""
Iterate over the keys in the session data.
"""
# try memcache first
mc = memcache.get('sid-'+str(self.session.key()))
if mc is not None:
for k in mc:
yield k
else:
for k in self._get():
yield k.keyname
def __str__(self):
"""
Return string representation.
"""
return ', '.join(['("%s" = "%s")' % (k, self[k]) for k in self])
def _set_memcache(self):
"""
Set a memcache object with all the session date. Optionally you can
add a key and value to the memcache for put operations.
"""
# Pull directly from the datastore in order to ensure that the
# information is as up to date as possible.
data = {}
sessiondata = self._get()
if sessiondata is not None:
for sd in sessiondata:
data[sd.keyname] = pickle.loads(sd.content)
memcache.set('sid-'+str(self.session.key()), data, \
self.session_expire_time)
def cycle_key(self):
self.sid = self.new_sid()
if len(self.session.sid) > 2:
self.session.sid.remove(self.session.sid[0])
self.session.sid.append(self.sid)
def flush(self):
self._delete_session()
self.__init__()