author | Lennard de Rijk <ljvderijk@gmail.com> |
Sat, 31 Jan 2009 13:48:48 +0000 | |
changeset 1107 | a878188e225c |
parent 323 | ff1a9aa48cfd |
permissions | -rw-r--r-- |
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""" |
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Caching framework. |
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This package defines set of cache backends that all conform to a simple API. |
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In a nutshell, a cache is a set of values -- which can be any object that |
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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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may be pickled -- identified by string keys. For the complete API, see |
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parents:
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the abstract BaseCache class in django.core.cache.backends.base. |
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Todd Larsen <tlarsen@google.com>
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Client code should not access a cache backend directly; instead it should |
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either use the "cache" variable made available here, or it should use the |
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parents:
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get_cache() function made available here. get_cache() takes a backend URI |
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parents:
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(e.g. "memcached://127.0.0.1:11211/") and returns an instance of a backend |
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Todd Larsen <tlarsen@google.com>
parents:
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cache class. |
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parents:
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See docs/cache.txt for information on the public API. |
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""" |
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from cgi import parse_qsl |
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from django.conf import settings |
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parents:
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from django.core import signals |
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from django.core.cache.backends.base import InvalidCacheBackendError |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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# Name for use in settings file --> name of module in "backends" directory. |
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Load ../vendor/django into trunk/app/django.
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parents:
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# Any backend scheme that is not in this dictionary is treated as a Python |
ff1a9aa48cfd
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parents:
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# import path to a custom backend. |
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BACKENDS = { |
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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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def get_cache(backend_uri): |
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if backend_uri.find(':') == -1: |
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raise InvalidCacheBackendError, "Backend URI must start with scheme://" |
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scheme, rest = backend_uri.split(':', 1) |
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if not rest.startswith('//'): |
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parents:
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raise InvalidCacheBackendError, "Backend URI must start with scheme://" |
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Todd Larsen <tlarsen@google.com>
parents:
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host = rest[2:] |
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qpos = rest.find('?') |
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if qpos != -1: |
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params = dict(parse_qsl(rest[qpos+1:])) |
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host = rest[2:qpos] |
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else: |
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params = {} |
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if host.endswith('/'): |
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host = host[:-1] |
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Pawel Solyga <Pawel.Solyga@gmail.com>
parents:
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if scheme in BACKENDS: |
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parents:
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module = __import__('django.core.cache.backends.%s' % BACKENDS[scheme], {}, {}, ['']) |
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parents:
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else: |
ff1a9aa48cfd
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parents:
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module = __import__(scheme, {}, {}, ['']) |
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return getattr(module, 'CacheClass')(host, params) |
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cache = get_cache(settings.CACHE_BACKEND) |
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parents:
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parents:
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# Some caches -- pythont-memcached in particular -- need to do a cleanup at the |
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parents:
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# end of a request cycle. If the cache provides a close() method, wire it up |
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# here. |
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if hasattr(cache, 'close'): |
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signals.request_finished.connect(cache.close) |
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