54 lines
1.7 KiB
Python
54 lines
1.7 KiB
Python
#!/usr/bin/env python
|
|
|
|
__author__ = "Abhinav Sarkar <abhinav@abhinavsarkar.net>"
|
|
__version__ = "0.2"
|
|
__license__ = "GNU Lesser General Public License"
|
|
__package__ = "lastfm.mixins"
|
|
|
|
try:
|
|
from threading import Lock
|
|
except ImportError:
|
|
from dummy_threading import Lock
|
|
|
|
class Cacheable(object):
|
|
registry = {}
|
|
_lock = Lock()
|
|
|
|
def __new__(cls, *args, **kwds):
|
|
subject = None
|
|
if 'subject' in kwds and not cls.__name__.startswith('Weekly'):
|
|
subject = kwds['subject']
|
|
#del kwds['subject']
|
|
|
|
if 'bypass_registry' in kwds:
|
|
del kwds['bypass_registry']
|
|
inst = object.__new__(cls)
|
|
inst.init(*args, **kwds)
|
|
return inst
|
|
|
|
key = cls._hash_func(*args, **kwds)
|
|
if subject is not None:
|
|
key = (hash(subject), key)
|
|
|
|
Cacheable._lock.acquire()
|
|
try:
|
|
inst, already_registered = Cacheable.register(object.__new__(cls), key)
|
|
if not already_registered:
|
|
inst.init(*args, **kwds)
|
|
finally:
|
|
Cacheable._lock.release()
|
|
return inst
|
|
|
|
@staticmethod
|
|
def register(ob, key):
|
|
if not ob.__class__ in Cacheable.registry:
|
|
Cacheable.registry[ob.__class__] = {}
|
|
if key in Cacheable.registry[ob.__class__]:
|
|
ob = Cacheable.registry[ob.__class__][key]
|
|
#print "already registered: %s" % repr(ob)
|
|
return (ob, True)
|
|
else:
|
|
#print "not already registered: %s" % ob.__class__
|
|
Cacheable.registry[ob.__class__][key] = ob
|
|
return (ob, False)
|