Cache object
Cache object is general purpose object-property interface.
NOTE: This library is under rebooting. Do not update from under 0.6.x if you mind continuous rewriting.
Example
There is some pre-defined common types.
in-memory, memcache and redis backends are included. And its common general interfaces too.
>>> from cacheobj.redis import LocalRedisObject >>> class UserCache(LocalRedisObject): ... _properties = ['username', 'name'] ... >>> user = UserCache(id=10) >>> print user.username None >>> user.username = 'username' >>> user.name = 'Real Name' >>> print user.username username >>> user10 = UserCache(id=10) >>> print user10.username username
Cache is stored with class name and given id.
>>> print user.get('username', use_cache=True) username
If you don't want to hit backend again, there is use_cache option for local memory cache.
For non-local cache backend, try a easy generator.
>>> from cacheobj.redis import get_redis_object >>> import redis >>> MyRedisObject = get_redis_object(redis.ConnectionPool()) # any connection pool >>> class MyUserCache(MyRedisObject): ... pass ...
Custom Backend
Upper examples are shortcut for basic configuration.
>>> from cacheobj import SimpleCacheObject >>> from cacheobj.backend.memcache import MemcacheBackend >>> def get_backend(): ... return MemcacheBackend(['127.0.0.1:11211']) ... >>> class UserCache(SimpleCacheObject): ... _backend_generator = staticmethod(get_backend) ... _properties = ['username', 'name'] ...
This object works as upper UserCache object. You can put custom backend with this.
See source code to write a backend. It is just a few lines.
Composite Example
You can composite multiple backends for an object.
>>> from cacheobj import CacheObject >>> from cacheobj.backend.memory import MemoryBackend >>> from cacheobj.backend.memcache import MemcacheBackend >>> from cacheobj.backend.redis import RedisBackend >>> >>> memory = MemoryBackend() >>> memcache = MemcacheBackend() >>> redis = RedisBackend() >>> >>> class CompositeCache(CacheObject): ... _backends = { ... memory: ['mem1', 'mem2'], ... memcache: ['mc1', 'mc2'], ... redis: ['redis1', 'redis2'], ... } ... >>> c = CompositeCache() >>> c.mem1 # with backend memory >>> c.mc1 # with backend memcache >>> c.redis1 # with backend redis