def __save_catalog__(self, sub_catalog, namespace=None):
"""
@param::sub_catalog: the catelog object contains feature metadata
@param::namespace: the string namespace of catalog
return None
"""
# check edge case
if sub_catalog == None:
raise Exception('> save_catalog: (sub)catalog can not be None!')
if not isinstance(sub_catalog, dict):
raise Exception(
'> save_catalog: (sub)catalog is not dictionary type!')
# save (sub)catalog into flat file
catalog = {}
namespace = self.__build_canonical_namespace__(namespace)
if file_exist(self.path, self.filename):
bytes_obj = read_binary_file(self.path, self.filename)
catalog = pl.loads(bytes_obj)
if len(sub_catalog) == 0:
# delete the namespace associate with empty sub catalog.
del catalog[namespace]
else:
catalog[namespace] = sub_catalog
else:
if len(sub_catalog) > 0:
catalog[namespace] = sub_catalog
dumps = pl.dumps(catalog)
write_binary_file(self.path, self.filename, dumps)
def namespaces(self, **kwargs):
"""
@param::kwargs: keyword parameter list
return list of canonical namespace objects and the counts of features in that namespace
"""
catalog = {}
if file_exist(self.path, self.filename):
# read and deserialize catalog object
bytes_obj = read_binary_file(self.path, self.filename)
catalog = pl.loads(bytes_obj)
return catalog.keys(), list(map(len, catalog.values()))
def __get_catalog__(self, namespace=None):
"""
@param::namespace: the string namespace of catalog
return the catalog object or None
"""
catalog_rtn = {}
namespace = self.__build_canonical_namespace__(namespace)
if file_exist(self.path, self.filename):
# read and deserialize catalog object
bytes_obj = read_binary_file(self.path, self.filename)
catalog = pl.loads(bytes_obj)
if namespace in catalog:
catalog_rtn = catalog[namespace]
return catalog_rtn
def read(self, namespace='default', match_child=True, **kwargs):
"""
@param::namespace: the namespace in string
@param::match_child: boolean value indicate whether match sub namespaces
@param::kwargs: the keyword parameter list
return a dictionary of {uid:feature meta data}
"""
feature_dict = {}
if file_exist(self.path, self.filename):
bytes_obj = read_binary_file(self.path, self.filename)
catalog = pl.loads(bytes_obj)
canonical_ns = self.__build_canonical_namespace__(namespace)
if match_child:
for key_ns in catalog:
if self.__namespace_match__(canonical_ns, key_ns):
feature_dict.update(catalog[key_ns])
else:
if canonical_ns in catalog:
feature_dict = catalog[canonical_ns]
return feature_dict
def __check_feature_name_uniqueness__(self, feature):
"""
@param::feature: the feature metadata object.
return boolean value of uniqueness of feature name in given namespace.
"""
if file_exist(self.path, self.filename):
# read and deserialize catalog object
bytes_obj = read_binary_file(self.path, self.filename)
catalog = pl.loads(bytes_obj)
# check uniquess
feature_name = feature.name
namespace = feature.namespace
uid = feature.uid
canonical_ns = self.__build_canonical_namespace__(namespace)
if canonical_ns in catalog:
for _, feature in catalog[canonical_ns].items():
if feature.name.lower() == feature_name.lower(
) and feature.uid != uid:
return False
return True
def delete(self, uid, **kwargs):
filename = '%s.dill' % (uid)
if file_exist(self.path, filename):
delete_file(self.path, filename)
def read(self, uid, **kwargs):
filename = '%s.dill' % (uid)
if file_exist(self.path, filename):
content = read_binary_file(self.path, filename)
return content
return None