python.utils.AtlRunQueryCache.Cache Class Reference

Inheritance diagram for python.utils.AtlRunQueryCache.Cache:

Collaboration diagram for python.utils.AtlRunQueryCache.Cache:

Public Member Functions
	__init__ (self, cachedir, form)
	__call__ (self, f, *args, **kwds)

Public Attributes
	cachedir = cachedir.rstrip('/') if os.path.exists(cachedir) else None
	form = form

Protected Attributes
dict	_cache = {}

Private Member Functions
	__name_pickle_cache (self, key)
	__write_to_cache (self, key, value)
	__is_cached (self, key)

Detailed Description

Definition at line 11 of file AtlRunQueryCache.py.

Constructor & Destructor Documentation

__init__()

python.utils.AtlRunQueryCache.Cache.__init__	(		self,
			cachedir,
			form )

Definition at line 12 of file AtlRunQueryCache.py.

    def __init__(self,cachedir,form):
        self._cache = {}
        self.cachedir = cachedir.rstrip('/') if os.path.exists(cachedir) else None
        self.form = form
        if self.cachedir:
            print ("Initializing the cache at",cachedir.rstrip('/'))
            
 

Member Function Documentation

__call__()

python.utils.AtlRunQueryCache.Cache.__call__	(		self,
			f,
		*	args,
		**	kwds )

Definition at line 20 of file AtlRunQueryCache.py.

    def __call__(self, f, *args, **kwds):
        if not self.cachedir:
            return f  # caching is automatically disabled if no cache directory exists
 
        print ("Providing cache functionality for function '%s()'" % f.func_name)
        def newf(*args, **kwds):
            key = kwds['cachekey']
            if not self.__is_cached(key):
                self.__write_to_cache(key,f(*args, **kwds))
            else:
                if DEBUG:
                    print ("DEBUG: returning cached value for '%s'" % (self.form % key))
                pass
            return self._cache[key]
        return newf
 

__is_cached()

python.utils.AtlRunQueryCache.Cache.__is_cached ( self, key )

private

Definition at line 55 of file AtlRunQueryCache.py.

    def __is_cached(self,key):
        # check transient cache
        if key in self._cache:
            return True
 
        # check for pickled version
        pfname = self.__name_pickle_cache(key)
        try:
            pf = open( pfname, 'r' )
        except OSError:
            if DEBUG:
                print ('DEBUG: could not read from cache: ' + pfname)
            return False
        try:
            self._cache[key] = pickle.load(pf)
        except pickle.UnpicklingError as err:
            print ("ERROR: could not unpickle %s (%s)" % (pfname, err))
            sys.exit(1)
        pf.close()
        return True
 
 
 
 
 

__name_pickle_cache()

python.utils.AtlRunQueryCache.Cache.__name_pickle_cache ( self, key )

private

Definition at line 36 of file AtlRunQueryCache.py.

    def __name_pickle_cache(self,key):
        filename = self.form % key
        return '%s/%s.pickle' % (self.cachedir, filename)
 
 

__write_to_cache()

python.utils.AtlRunQueryCache.Cache.__write_to_cache ( self, key, value )

private

Definition at line 41 of file AtlRunQueryCache.py.

    def __write_to_cache(self,key, value):
        # put into transient cache
        self._cache[key] = value
 
        # store pickled version
        pfname = self.__name_pickle_cache(key)
        pf = open( pfname, 'w' )
        try:
            pickle.dump(value, pf)
        except pickle.PicklingError as err:
            print ('ERROR: could not write to cache: %s (%s)' % (pfname, err))
            sys.exit(1)
        pf.close()
        

Member Data Documentation

_cache

dict python.utils.AtlRunQueryCache.Cache._cache = {}

protected

Definition at line 13 of file AtlRunQueryCache.py.

cachedir

python.utils.AtlRunQueryCache.Cache.cachedir = cachedir.rstrip('/') if os.path.exists(cachedir) else None

Definition at line 14 of file AtlRunQueryCache.py.

form

python.utils.AtlRunQueryCache.Cache.form = form

Definition at line 15 of file AtlRunQueryCache.py.

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The documentation for this class was generated from the following file:

• AtlRunQueryCache.py