0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
1 |
"""HTTP cache managers |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
2 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
3 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
4 |
:organization: Logilab |
762
|
5 |
:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), all rights reserved. |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
6 |
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
7 |
""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
8 |
__docformat__ = "restructuredtext en" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
9 |
|
1016
|
10 |
from datetime import datetime |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
11 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
12 |
# time delta usable to convert localized time to GMT time |
1016
|
13 |
GMTOFFSET = - (datetime.now() - datetime.utcnow()) |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
14 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
15 |
class NoHTTPCacheManager(object): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
16 |
"""default cache manager: set no-cache cache control policy""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
17 |
def __init__(self, view): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
18 |
self.view = view |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
19 |
self.req = view.req |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
20 |
self.rset = view.rset |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
21 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
22 |
def set_headers(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
23 |
self.req.set_header('Cache-control', 'no-cache') |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
24 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
25 |
class MaxAgeHTTPCacheManager(NoHTTPCacheManager): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
26 |
"""max-age cache manager: set max-age cache control policy, with max-age |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
27 |
specified with the `cache_max_age` attribute of the view |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
28 |
""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
29 |
def set_headers(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
30 |
self.req.set_header('Cache-control', |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
31 |
'max-age=%s' % self.view.cache_max_age) |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
32 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
33 |
class EtagHTTPCacheManager(NoHTTPCacheManager): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
34 |
"""etag based cache manager for startup views |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
35 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
36 |
* etag is generated using the view name and the user's groups |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
37 |
* set policy to 'must-revalidate' and expires to the current time to force |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
38 |
revalidation on each request |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
39 |
""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
40 |
# GMT time required |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
41 |
date_format = "%a, %d %b %Y %H:%M:%S GMT" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
42 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
43 |
def etag(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
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|
44 |
return self.view.id + '/' + ','.join(sorted(self.req.user.groups)) |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
45 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
46 |
def max_age(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
47 |
# 0 to actually force revalidation |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
48 |
return 0 |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
49 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
50 |
def last_modified(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
51 |
return self.view.last_modified() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
52 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
53 |
def set_headers(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
54 |
req = self.req |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
55 |
try: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
56 |
req.set_header('Etag', '"%s"' % self.etag()) |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
57 |
except NoEtag: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
58 |
self.req.set_header('Cache-control', 'no-cache') |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
59 |
return |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
60 |
req.set_header('Cache-control', |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
61 |
'must-revalidate;max-age=%s' % self.max_age()) |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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|
62 |
mdate = self.last_modified() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
63 |
req.set_header('Last-modified', mdate.strftime(self.date_format)) |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
64 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
65 |
class EntityHTTPCacheManager(EtagHTTPCacheManager): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
66 |
"""etag based cache manager for view displaying a single entity |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
67 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
68 |
* etag is generated using entity's eid, the view name and the user's groups |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
69 |
* get last modified time from the entity definition (this may not be the |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
70 |
entity's modification time since a view may include some related entities |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
71 |
with a modification time to consider) using the `last_modified` method |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
72 |
""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
73 |
def etag(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
74 |
if self.rset is None or len(self.rset) == 0: # entity startup view for instance |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
75 |
return super(EntityHTTPCacheManager, self).etag() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
76 |
if len(self.rset) > 1: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
77 |
raise NoEtag() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
78 |
etag = super(EntityHTTPCacheManager, self).etag() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
79 |
eid = self.rset[0][0] |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
80 |
if self.req.user.owns(eid): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
81 |
etag += ',owners' |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
82 |
return str(eid) + '/' + etag |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
83 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
84 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
85 |
class NoEtag(Exception): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
86 |
"""an etag can't be generated""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
87 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
88 |
__all__ = ('GMTOFFSET', |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
89 |
'NoHTTPCacheManager', 'MaxAgeHTTPCacheManager', |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
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|
90 |
'EtagHTTPCacheManager', 'EntityHTTPCacheManager') |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
91 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
92 |
# monkey patching, so view doesn't depends on this module and we have all |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
93 |
# http cache related logic here |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
94 |
|
1149
|
95 |
from cubicweb import view as viewmod |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
96 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
97 |
def set_http_cache_headers(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
98 |
self.http_cache_manager(self).set_headers() |
1149
|
99 |
viewmod.View.set_http_cache_headers = set_http_cache_headers |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
100 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
101 |
def last_modified(self): |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
102 |
"""return the date/time where this view should be considered as |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
103 |
modified. Take care of possible related objects modifications. |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
104 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
105 |
/!\ must return GMT time /!\ |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
106 |
""" |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
107 |
# XXX check view module's file modification time in dev mod ? |
1016
|
108 |
ctime = datetime.utcnow() |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
109 |
if self.cache_max_age: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
110 |
mtime = self.req.header_if_modified_since() |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
111 |
if mtime: |
1016
|
112 |
tdelta = (ctime - mtime) |
|
113 |
if tdelta.days * 24*60*60 + tdelta.seconds > self.cache_max_age: |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
114 |
mtime = ctime |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
115 |
else: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
116 |
mtime = ctime |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
117 |
else: |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
118 |
mtime = ctime |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
119 |
# mtime = ctime will force page rerendering |
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
120 |
return mtime |
1149
|
121 |
viewmod.View.last_modified = last_modified |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
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changeset
|
122 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
123 |
# configure default caching |
1149
|
124 |
viewmod.View.http_cache_manager = NoHTTPCacheManager |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
125 |
# max-age=0 to actually force revalidation when needed |
1149
|
126 |
viewmod.View.cache_max_age = 0 |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
127 |
|
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
128 |
|
1149
|
129 |
viewmod.EntityView.http_cache_manager = EntityHTTPCacheManager |
0
Adrien Di Mascio <Adrien.DiMascio@logilab.fr>
parents:
diff
changeset
|
130 |
|
1149
|
131 |
viewmod.StartupView.http_cache_manager = MaxAgeHTTPCacheManager |
|
132 |
viewmod.StartupView.cache_max_age = 60*60*2 # stay in http cache for 2 hours by default |