SickGear/lib/subliminal/cache.py
echel0n 0d9fbc1ad7 Welcome to our SickBeard-TVRage Edition ...
This version of SickBeard uses both TVDB and TVRage to search and gather it's series data from allowing you to now have access to and download shows that you couldn't before because of being locked into only what TheTVDB had to offer.

Also this edition is based off the code we used in our XEM editon so it does come with scene numbering support as well as all the other features our XEM edition has to offer.

Please before using this with your existing database (sickbeard.db) please make a backup copy of it and delete any other database files such as cache.db and failed.db if present, we HIGHLY recommend starting out with no database files at all to make this a fresh start but the choice is at your own risk!

Enjoy!
2014-03-09 22:39:12 -07:00

134 lines
4.5 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2012 Nicolas Wack <wackou@gmail.com>
#
# This file is part of subliminal.
#
# subliminal is free software; you can redistribute it and/or modify it under
# the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# subliminal is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with subliminal. If not, see <http://www.gnu.org/licenses/>.
from collections import defaultdict
from functools import wraps
import logging
import os.path
import threading
try:
import cPickle as pickle
except ImportError:
import pickle
__all__ = ['Cache', 'cachedmethod']
logger = logging.getLogger("subliminal")
class Cache(object):
"""A Cache object contains cached values for methods. It can have
separate internal caches, one for each service
"""
def __init__(self, cache_dir):
self.cache_dir = cache_dir
self.cache = defaultdict(dict)
self.lock = threading.RLock()
def __del__(self):
for service_name in self.cache:
self.save(service_name)
def cache_location(self, service_name):
return os.path.join(self.cache_dir, 'subliminal_%s.cache' % service_name)
def load(self, service_name):
with self.lock:
if service_name in self.cache:
# already loaded
return
self.cache[service_name] = defaultdict(dict)
filename = self.cache_location(service_name)
logger.debug(u'Cache: loading cache from %s' % filename)
try:
self.cache[service_name] = pickle.load(open(filename, 'rb'))
except IOError:
logger.info('Cache: Cache file "%s" doesn\'t exist, creating it' % filename)
except EOFError:
logger.error('Cache: cache file "%s" is corrupted... Removing it.' % filename)
os.remove(filename)
def save(self, service_name):
filename = self.cache_location(service_name)
logger.debug(u'Cache: saving cache to %s' % filename)
with self.lock:
pickle.dump(self.cache[service_name], open(filename, 'wb'))
def clear(self, service_name):
try:
os.remove(self.cache_location(service_name))
except OSError:
pass
self.cache[service_name] = defaultdict(dict)
def cached_func_key(self, func, cls=None):
try:
cls = func.im_class
except:
pass
return ('%s.%s' % (cls.__module__, cls.__name__), func.__name__)
def function_cache(self, service_name, func):
func_key = self.cached_func_key(func)
return self.cache[service_name][func_key]
def cache_for(self, service_name, func, args, result):
# no need to lock here, dict ops are atomic
self.function_cache(service_name, func)[args] = result
def cached_value(self, service_name, func, args):
"""Raises KeyError if not found"""
# no need to lock here, dict ops are atomic
return self.function_cache(service_name, func)[args]
def cachedmethod(function):
"""Decorator to make a method use the cache.
.. note::
This can NOT be used with static functions, it has to be used on
methods of some class
"""
@wraps(function)
def cached(*args):
c = args[0].config.cache
service_name = args[0].__class__.__name__
func_key = c.cached_func_key(function, cls=args[0].__class__)
func_cache = c.cache[service_name][func_key]
# we need to remove the first element of args for the key, as it is the
# instance pointer and we don't want the cache to know which instance
# called it, it is shared among all instances of the same class
key = args[1:]
if key in func_cache:
result = func_cache[key]
logger.debug(u'Using cached value for %s(%s), returns: %s' % (func_key, key, result))
return result
result = function(*args)
# note: another thread could have already cached a value in the
# meantime, but that's ok as we prefer to keep the latest value in
# the cache
func_cache[key] = result
return result
return cached