Fixed #21125 -- Removed support for cache URI syntax

This commit is contained in:
Curtis Maloney 2013-09-19 18:38:56 +10:00 committed by Tim Graham
parent 7fec5a2240
commit 4e9f800742
3 changed files with 25 additions and 91 deletions

View File

@ -8,9 +8,9 @@ the abstract BaseCache class in django.core.cache.backends.base.
Client code should not access a cache backend directly; instead it should
either use the "cache" variable made available here, or it should use the
get_cache() function made available here. get_cache() takes a backend URI
(e.g. "memcached://127.0.0.1:11211/") and returns an instance of a backend
cache class.
get_cache() function made available here. get_cache() takes a CACHES alias or a
backend path and config parameters, and returns an instance of a backend cache
class.
See docs/topics/cache.txt for information on the public API.
"""
@ -29,78 +29,17 @@ __all__ = [
'get_cache', 'cache', 'DEFAULT_CACHE_ALIAS'
]
# Name for use in settings file --> name of module in "backends" directory.
# Any backend scheme that is not in this dictionary is treated as a Python
# import path to a custom backend.
BACKENDS = {
'memcached': 'memcached',
'locmem': 'locmem',
'file': 'filebased',
'db': 'db',
'dummy': 'dummy',
}
DEFAULT_CACHE_ALIAS = 'default'
def parse_backend_uri(backend_uri):
"""
Converts the "backend_uri" into a cache scheme ('db', 'memcached', etc), a
host and any extra params that are required for the backend. Returns a
(scheme, host, params) tuple.
"""
if backend_uri.find(':') == -1:
raise InvalidCacheBackendError("Backend URI must start with scheme://")
scheme, rest = backend_uri.split(':', 1)
if not rest.startswith('//'):
raise InvalidCacheBackendError("Backend URI must start with scheme://")
host = rest[2:]
qpos = rest.find('?')
if qpos != -1:
params = dict(parse_qsl(rest[qpos+1:]))
host = rest[2:qpos]
else:
params = {}
if host.endswith('/'):
host = host[:-1]
return scheme, host, params
if DEFAULT_CACHE_ALIAS not in settings.CACHES:
raise ImproperlyConfigured("You must define a '%s' cache" % DEFAULT_CACHE_ALIAS)
def parse_backend_conf(backend, **kwargs):
"""
Helper function to parse the backend configuration
that doesn't use the URI notation.
"""
# Try to get the CACHES entry for the given backend name first
conf = settings.CACHES.get(backend, None)
if conf is not None:
args = conf.copy()
args.update(kwargs)
backend = args.pop('BACKEND')
location = args.pop('LOCATION', '')
return backend, location, args
else:
try:
# Trying to import the given backend, in case it's a dotted path
import_by_path(backend)
except ImproperlyConfigured as e:
raise InvalidCacheBackendError("Could not find backend '%s': %s" % (
backend, e))
location = kwargs.pop('LOCATION', '')
return backend, location, kwargs
def get_cache(backend, **kwargs):
"""
Function to load a cache backend dynamically. This is flexible by design
to allow different use cases:
To load a backend with the old URI-based notation::
cache = get_cache('locmem://')
To load a backend that is pre-defined in the settings::
cache = get_cache('default')
@ -114,16 +53,23 @@ def get_cache(backend, **kwargs):
"""
try:
if '://' in backend:
# for backwards compatibility
backend, location, params = parse_backend_uri(backend)
if backend in BACKENDS:
backend = 'django.core.cache.backends.%s' % BACKENDS[backend]
params.update(kwargs)
mod = importlib.import_module(backend)
backend_cls = mod.CacheClass
# Try to get the CACHES entry for the given backend name first
try:
conf = settings.CACHES[backend]
except KeyError:
try:
# Trying to import the given backend, in case it's a dotted path
import_by_path(backend)
except ImproperlyConfigured as e:
raise InvalidCacheBackendError("Could not find backend '%s': %s" % (
backend, e))
location = kwargs.pop('LOCATION', '')
params = kwargs
else:
backend, location, params = parse_backend_conf(backend, **kwargs)
params = conf.copy()
params.update(kwargs)
backend = params.pop('BACKEND')
location = params.pop('LOCATION', '')
backend_cls = import_by_path(backend)
except (AttributeError, ImportError, ImproperlyConfigured) as e:
raise InvalidCacheBackendError(

View File

@ -414,6 +414,10 @@ Miscellaneous
Rationale behind this is removal of dependency of non-contrib code on
contrib applications.
* The old cache URI syntax (e.g. ``"locmem://"``) is no longer supported. It
still worked, even though it was not documented or officially supported. If
you're still using it, please update to the current :setting:`CACHES` syntax.
Features deprecated in 1.7
==========================

18
tests/cache/tests.py vendored
View File

@ -857,10 +857,6 @@ class DBCacheTests(BaseCacheTests, TransactionTestCase):
self.cache = get_cache(self.backend_name, LOCATION=self._table_name, OPTIONS={'MAX_ENTRIES': 30, 'CULL_FREQUENCY': 0})
self.perform_cull_test(50, 18)
def test_old_initialization(self):
self.cache = get_cache('db://%s?max_entries=30&cull_frequency=0' % self._table_name)
self.perform_cull_test(50, 18)
def test_second_call_doesnt_crash(self):
with six.assertRaisesRegex(self, management.CommandError,
"Cache table 'test cache table' could not be created"):
@ -956,10 +952,6 @@ class LocMemCacheTests(unittest.TestCase, BaseCacheTests):
self.cache = get_cache(self.backend_name, OPTIONS={'MAX_ENTRIES': 30, 'CULL_FREQUENCY': 0})
self.perform_cull_test(50, 19)
def test_old_initialization(self):
self.cache = get_cache('locmem://?max_entries=30&cull_frequency=0')
self.perform_cull_test(50, 19)
def test_multiple_caches(self):
"Check that multiple locmem caches are isolated"
mirror_cache = get_cache(self.backend_name)
@ -1075,10 +1067,6 @@ class FileBasedCacheTests(unittest.TestCase, BaseCacheTests):
def test_cull(self):
self.perform_cull_test(50, 29)
def test_old_initialization(self):
self.cache = get_cache('file://%s?max_entries=30' % self.dirname)
self.perform_cull_test(50, 29)
class CustomCacheKeyValidationTests(unittest.TestCase):
"""
@ -1088,7 +1076,7 @@ class CustomCacheKeyValidationTests(unittest.TestCase):
"""
def test_custom_key_validation(self):
cache = get_cache('cache.liberal_backend://')
cache = get_cache('cache.liberal_backend.CacheClass')
# this key is both longer than 250 characters, and has spaces
key = 'some key with spaces' * 15
@ -1100,10 +1088,6 @@ class CustomCacheKeyValidationTests(unittest.TestCase):
class GetCacheTests(unittest.TestCase):
def test_simple(self):
cache = get_cache('locmem://')
from django.core.cache.backends.locmem import LocMemCache
self.assertIsInstance(cache, LocMemCache)
from django.core.cache import cache
self.assertIsInstance(cache, get_cache('default').__class__)