author | Pawel Solyga <Pawel.Solyga@gmail.com> |
Fri, 22 Aug 2008 13:44:50 +0000 | |
changeset 99 | 8c38b546a3cf |
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 |
""" |
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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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2 |
Caching framework. |
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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3 |
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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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This package defines set of cache backends that all conform to a simple API. |
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Todd Larsen <tlarsen@google.com>
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5 |
In a nutshell, a cache is a set of values -- which can be any object that |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
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parents:
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may be pickled -- identified by string keys. For the complete API, see |
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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7 |
the abstract BaseCache class in django.core.cache.backends.base. |
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 |
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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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9 |
Client code should not access a cache backend directly; instead it should |
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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either use the "cache" variable made available here, or it should use the |
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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changeset
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11 |
get_cache() function made available here. get_cache() takes a backend URI |
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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(e.g. "memcached://127.0.0.1:11211/") and returns an instance of a backend |
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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13 |
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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changeset
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14 |
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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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15 |
See docs/cache.txt for information on the public API. |
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Todd Larsen <tlarsen@google.com>
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16 |
""" |
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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>
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from cgi import parse_qsl |
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19 |
from django.conf import settings |
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from django.core.cache.backends.base import InvalidCacheBackendError |
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21 |
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22 |
BACKENDS = { |
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# name for use in settings file --> name of module in "backends" directory |
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Todd Larsen <tlarsen@google.com>
parents:
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'memcached': 'memcached', |
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'locmem': 'locmem', |
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'file': 'filebased', |
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'db': 'db', |
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'dummy': 'dummy', |
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} |
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DEPRECATED_BACKENDS = { |
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# deprecated backend --> replacement module |
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'simple': 'locmem', |
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} |
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Todd Larsen <tlarsen@google.com>
parents:
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Todd Larsen <tlarsen@google.com>
parents:
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def get_cache(backend_uri): |
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if backend_uri.find(':') == -1: |
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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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raise InvalidCacheBackendError, "Backend URI must start with scheme://" |
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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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scheme, rest = backend_uri.split(':', 1) |
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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if not rest.startswith('//'): |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
41 |
raise InvalidCacheBackendError, "Backend URI must start with scheme://" |
03e267d67478
Major reorganization of the soc svn repo, to merge into a single App Engine
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
|
42 |
if scheme in DEPRECATED_BACKENDS: |
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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43 |
import warnings |
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warnings.warn("'%s' backend is deprecated. Use '%s' instead." % |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
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(scheme, DEPRECATED_BACKENDS[scheme]), DeprecationWarning) |
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Major reorganization of the soc svn repo, to merge into a single App Engine
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parents:
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scheme = DEPRECATED_BACKENDS[scheme] |
03e267d67478
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Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
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47 |
if scheme not in BACKENDS: |
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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48 |
raise InvalidCacheBackendError, "%r is not a valid cache backend" % scheme |
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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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|
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Todd Larsen <tlarsen@google.com>
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50 |
host = rest[2:] |
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Todd Larsen <tlarsen@google.com>
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51 |
qpos = rest.find('?') |
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if qpos != -1: |
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53 |
params = dict(parse_qsl(rest[qpos+1:])) |
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parents:
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54 |
host = rest[2:qpos] |
03e267d67478
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Todd Larsen <tlarsen@google.com>
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else: |
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Todd Larsen <tlarsen@google.com>
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params = {} |
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parents:
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if host.endswith('/'): |
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58 |
host = host[:-1] |
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cache_class = getattr(__import__('django.core.cache.backends.%s' % BACKENDS[scheme], {}, {}, ['']), 'CacheClass') |
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61 |
return cache_class(host, params) |
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Todd Larsen <tlarsen@google.com>
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03e267d67478
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cache = get_cache(settings.CACHE_BACKEND) |