mirror of
https://github.com/ets-labs/python-dependency-injector.git
synced 2024-11-22 17:47:02 +03:00
67 lines
2.0 KiB
Python
67 lines
2.0 KiB
Python
"""Catalog module."""
|
|
|
|
from six import iteritems
|
|
|
|
from .errors import Error
|
|
from .utils import is_provider
|
|
|
|
|
|
class CatalogMetaClass(type):
|
|
|
|
"""Providers catalog meta class."""
|
|
|
|
def __new__(mcs, class_name, bases, attributes):
|
|
"""Meta class factory."""
|
|
providers = dict()
|
|
new_attributes = dict()
|
|
for name, value in attributes.iteritems():
|
|
if is_provider(value):
|
|
providers[name] = value
|
|
new_attributes[name] = value
|
|
|
|
cls = type.__new__(mcs, class_name, bases, new_attributes)
|
|
cls.providers = cls.providers.copy()
|
|
cls.providers.update(providers)
|
|
return cls
|
|
|
|
|
|
class AbstractCatalog(object):
|
|
|
|
"""Abstract providers catalog."""
|
|
|
|
providers = dict()
|
|
|
|
__slots__ = ('providers', '__used_providers__',)
|
|
__metaclass__ = CatalogMetaClass
|
|
|
|
def __init__(self, *used_providers):
|
|
"""Initializer."""
|
|
self.__used_providers__ = set(used_providers)
|
|
|
|
def __getattribute__(self, item):
|
|
"""Return providers."""
|
|
attribute = super(AbstractCatalog, self).__getattribute__(item)
|
|
if item in ('providers', '__used_providers__',):
|
|
return attribute
|
|
|
|
if attribute not in self.__used_providers__:
|
|
raise Error('Provider \'{0}\' '.format(item) +
|
|
'is not listed in dependencies')
|
|
return attribute
|
|
|
|
@classmethod
|
|
def filter(cls, provider_type):
|
|
"""Return dict of providers, that are instance of provided type."""
|
|
return dict([(name, provider)
|
|
for name, provider in iteritems(cls.providers)
|
|
if isinstance(provider, provider_type)])
|
|
|
|
@classmethod
|
|
def override(cls, overriding):
|
|
"""Override current catalog providers by overriding catalog providers.
|
|
|
|
:type overriding: AbstractCatalog
|
|
"""
|
|
for name, provider in iteritems(overriding.providers):
|
|
cls.providers[name].override(provider)
|