1234567891011121314151617181920212223242526272829303132333435363738394041424344454647 |
- #
- # SPDX-License-Identifier: GPL-2.0-only
- #
- class ClassRegistryMeta(type):
- """Give each ClassRegistry their own registry"""
- def __init__(cls, name, bases, attrs):
- cls.registry = {}
- type.__init__(cls, name, bases, attrs)
- class ClassRegistry(type, metaclass=ClassRegistryMeta):
- """Maintain a registry of classes, indexed by name.
- Note that this implementation requires that the names be unique, as it uses
- a dictionary to hold the classes by name.
- The name in the registry can be overridden via the 'name' attribute of the
- class, and the 'priority' attribute controls priority. The prioritized()
- method returns the registered classes in priority order.
- Subclasses of ClassRegistry may define an 'implemented' property to exert
- control over whether the class will be added to the registry (e.g. to keep
- abstract base classes out of the registry)."""
- priority = 0
- def __init__(cls, name, bases, attrs):
- super(ClassRegistry, cls).__init__(name, bases, attrs)
- try:
- if not cls.implemented:
- return
- except AttributeError:
- pass
- try:
- cls.name
- except AttributeError:
- cls.name = name
- cls.registry[cls.name] = cls
- @classmethod
- def prioritized(tcls):
- return sorted(list(tcls.registry.values()),
- key=lambda v: (v.priority, v.name), reverse=True)
- def unregister(cls):
- for key in cls.registry.keys():
- if cls.registry[key] is cls:
- del cls.registry[key]
|