django1/django/core/cache/__init__.py

67 lines
1.9 KiB
Python

"""
Caching framework.
This package defines set of cache backends that all conform to a simple API.
In a nutshell, a cache is a set of values -- which can be any object that
may be pickled -- identified by string keys. For the complete API, see
the abstract BaseCache class in django.core.cache.backends.base.
Client code should use the `cache` variable defined here to access the default
cache backend and look up non-default cache backends in the `caches` dict-like
object.
See docs/topics/cache.txt for information on the public API.
"""
from django.core import signals
from django.core.cache.backends.base import (
BaseCache,
CacheKeyWarning,
InvalidCacheBackendError,
InvalidCacheKey,
)
from django.utils.connection import BaseConnectionHandler, ConnectionProxy
from django.utils.module_loading import import_string
__all__ = [
"cache",
"caches",
"DEFAULT_CACHE_ALIAS",
"InvalidCacheBackendError",
"CacheKeyWarning",
"BaseCache",
"InvalidCacheKey",
]
DEFAULT_CACHE_ALIAS = "default"
class CacheHandler(BaseConnectionHandler):
settings_name = "CACHES"
exception_class = InvalidCacheBackendError
def create_connection(self, alias):
params = self.settings[alias].copy()
backend = params.pop("BACKEND")
location = params.pop("LOCATION", "")
try:
backend_cls = import_string(backend)
except ImportError as e:
raise InvalidCacheBackendError(
"Could not find backend '%s': %s" % (backend, e)
) from e
return backend_cls(location, params)
caches = CacheHandler()
cache = ConnectionProxy(caches, DEFAULT_CACHE_ALIAS)
def close_caches(**kwargs):
# Some caches need to do a cleanup at the end of a request cycle. If not
# implemented in a particular backend cache.close() is a no-op.
caches.close_all()
signals.request_finished.connect(close_caches)