Source code for univention.portal

#!/usr/bin/python3
#
# Univention Portal
#
# Copyright 2020-2022 Univention GmbH
#
# https://www.univention.de/
#
# All rights reserved.
#
# The source code of this program is made available
# under the terms of the GNU Affero General Public License version 3
# (GNU AGPL V3) as published by the Free Software Foundation.
#
# Binary versions of this program provided by Univention to you as
# well as other copyrighted, protected or trademarked materials like
# Logos, graphics, fonts, specific documentations and configurations,
# cryptographic keys etc. are subject to a license agreement between
# you and Univention and not subject to the GNU AGPL V3.
#
# In the case you use this program under the terms of the GNU AGPL V3,
# the program is provided in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License with the Debian GNU/Linux or Univention distribution in file
# /usr/share/common-licenses/AGPL-3; if not, see
# <https://www.gnu.org/licenses/>.
#

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)
[docs] @classmethod 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 sorted(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
[docs]def get_all_dynamic_classes(): for extension in Plugins("univention.portal.extensions"): yield extension
[docs]def get_dynamic_classes(klass_name): for extension in get_all_dynamic_classes(): if klass_name == extension.__name__: return extension raise KeyError(klass_name)