Source code for univention.udm.plugins

# -*- coding: utf-8 -*-
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import importlib
import os.path
from glob import glob

[docs]class Plugin(type): """ Meta class for plugins. """ def __new__(mcs, name, bases, attrs): new_cls = super(Plugin, mcs).__new__(mcs, name, bases, attrs) Plugins.add_plugin(new_cls) return new_cls
[docs]class Plugins(object): """ Register `Plugin` subclasses and iterate over them. """ _plugins = [] _imported = {} def __init__(self, python_path): """ :param str python_path: fully dotted Python path that the plugins will be found below """ self.python_path = python_path self._imported.setdefault(python_path, False) @classmethod
[docs] def add_plugin(cls, plugin): """ Called by `Plugin` meta class to register a new `Plugin` subclass. :param type plugin: a `Plugin` subclass """ cls._plugins.append(plugin)
def __iter__(self): """ Iterator for registered `Plugin` subclasses. :return: `Plugin` subclass :rtype: type """ self.load() for plugin in self._plugins: if plugin.__module__.startswith(self.python_path): yield plugin
[docs] def load(self): """Load plugins.""" if self._imported.get(self.python_path): return base_module = importlib.import_module(self.python_path) base_module_dir = os.path.dirname(base_module.__file__) path = os.path.join(base_module_dir, '*.py') for pymodule in glob(path): pymodule_name = os.path.basename(pymodule)[:-3] # without .py importlib.import_module('{}.{}'.format(self.python_path, pymodule_name)) self._imported[self.python_path] = True