author | Todd Larsen <tlarsen@google.com> |
Wed, 01 Oct 2008 06:03:53 +0000 | |
changeset 236 | d5302883f3ac |
parent 54 | 03e267d67478 |
child 323 | ff1a9aa48cfd |
permissions | -rw-r--r-- |
54
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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1 |
"Base Cache class." |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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from django.core.exceptions import ImproperlyConfigured |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
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class InvalidCacheBackendError(ImproperlyConfigured): |
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Todd Larsen <tlarsen@google.com>
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pass |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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8 |
class BaseCache(object): |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
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9 |
def __init__(self, params): |
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Major reorganization of the soc svn repo, to merge into a single App Engine
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10 |
timeout = params.get('timeout', 300) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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11 |
try: |
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timeout = int(timeout) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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13 |
except (ValueError, TypeError): |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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14 |
timeout = 300 |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
15 |
self.default_timeout = timeout |
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Todd Larsen <tlarsen@google.com>
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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def add(self, key, value, timeout=None): |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
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18 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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19 |
Set a value in the cache if the key does not already exist. If |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
20 |
timeout is given, that timeout will be used for the key; otherwise |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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21 |
the default cache timeout will be used. |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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22 |
""" |
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raise NotImplementedError |
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parents:
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Todd Larsen <tlarsen@google.com>
parents:
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25 |
def get(self, key, default=None): |
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Todd Larsen <tlarsen@google.com>
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26 |
""" |
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Todd Larsen <tlarsen@google.com>
parents:
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27 |
Fetch a given key from the cache. If the key does not exist, return |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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|
28 |
default, which itself defaults to None. |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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29 |
""" |
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Todd Larsen <tlarsen@google.com>
parents:
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raise NotImplementedError |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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31 |
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Todd Larsen <tlarsen@google.com>
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def set(self, key, value, timeout=None): |
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Todd Larsen <tlarsen@google.com>
parents:
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33 |
""" |
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Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
34 |
Set a value in the cache. If timeout is given, that timeout will be |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
35 |
used for the key; otherwise the default cache timeout will be used. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
36 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
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raise NotImplementedError |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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def delete(self, key): |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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40 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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41 |
Delete a key from the cache, failing silently. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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42 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
43 |
raise NotImplementedError |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
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def get_many(self, keys): |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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46 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
47 |
Fetch a bunch of keys from the cache. For certain backends (memcached, |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
48 |
pgsql) this can be *much* faster when fetching multiple values. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
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|
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
50 |
Returns a dict mapping each key in keys to its value. If the given |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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51 |
key is missing, it will be missing from the response dict. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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52 |
""" |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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|
53 |
d = {} |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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|
54 |
for k in keys: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
55 |
val = self.get(k) |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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56 |
if val is not None: |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
57 |
d[k] = val |
03e267d67478
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Todd Larsen <tlarsen@google.com>
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58 |
return d |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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03e267d67478
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Todd Larsen <tlarsen@google.com>
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def has_key(self, key): |
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Todd Larsen <tlarsen@google.com>
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61 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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62 |
Returns True if the key is in the cache and has not expired. |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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63 |
""" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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|
64 |
return self.get(key) is not None |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
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65 |
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
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66 |
__contains__ = has_key |