author | Todd Larsen <tlarsen@google.com> |
Thu, 13 Nov 2008 19:41:16 +0000 | |
changeset 478 | 613951c35706 |
parent 323 | ff1a9aa48cfd |
permissions | -rw-r--r-- |
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03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
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parents:
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1 |
"Base Cache class." |
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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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from django.core.exceptions import ImproperlyConfigured |
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class InvalidCacheBackendError(ImproperlyConfigured): |
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pass |
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|
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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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8 |
class BaseCache(object): |
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def __init__(self, params): |
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timeout = params.get('timeout', 300) |
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try: |
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timeout = int(timeout) |
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Major reorganization of the soc svn repo, to merge into a single App Engine
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13 |
except (ValueError, TypeError): |
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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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15 |
self.default_timeout = timeout |
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def add(self, key, value, timeout=None): |
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""" |
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Todd Larsen <tlarsen@google.com>
parents:
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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:
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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. |
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ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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Returns True if the value was stored, False otherwise. |
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""" |
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raise NotImplementedError |
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def get(self, key, default=None): |
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""" |
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Fetch a given key from the cache. If the key does not exist, return |
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default, which itself defaults to None. |
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""" |
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raise NotImplementedError |
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def set(self, key, value, timeout=None): |
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""" |
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Todd Larsen <tlarsen@google.com>
parents:
diff
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|
36 |
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
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|
37 |
used for the key; otherwise the default cache timeout will be used. |
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Todd Larsen <tlarsen@google.com>
parents:
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""" |
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Todd Larsen <tlarsen@google.com>
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raise NotImplementedError |
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def delete(self, key): |
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Todd Larsen <tlarsen@google.com>
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42 |
""" |
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Todd Larsen <tlarsen@google.com>
parents:
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Delete a key from the cache, failing silently. |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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""" |
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Todd Larsen <tlarsen@google.com>
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raise NotImplementedError |
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Todd Larsen <tlarsen@google.com>
parents:
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def get_many(self, keys): |
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48 |
""" |
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parents:
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Fetch a bunch of keys from the cache. For certain backends (memcached, |
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parents:
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50 |
pgsql) this can be *much* faster when fetching multiple values. |
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|
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Returns a dict mapping each key in keys to its value. If the given |
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parents:
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53 |
key is missing, it will be missing from the response dict. |
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Todd Larsen <tlarsen@google.com>
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""" |
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55 |
d = {} |
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for k in keys: |
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val = self.get(k) |
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if val is not None: |
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d[k] = val |
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return d |
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def has_key(self, key): |
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""" |
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Todd Larsen <tlarsen@google.com>
parents:
diff
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|
64 |
Returns True if the key is in the cache and has not expired. |
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Todd Larsen <tlarsen@google.com>
parents:
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|
65 |
""" |
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66 |
return self.get(key) is not None |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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323
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
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|
68 |
def __contains__(self, key): |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
changeset
|
69 |
""" |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
changeset
|
70 |
Returns True if the key is in the cache and has not expired. |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
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|
71 |
""" |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
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|
72 |
# This is a separate method, rather than just a copy of has_key(), |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
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|
73 |
# so that it always has the same functionality as has_key(), even |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
54
diff
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|
74 |
# if a subclass overrides it. |
ff1a9aa48cfd
Load ../vendor/django into trunk/app/django.
Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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75 |
return self.has_key(key) |