HGKeeper

# pyplugin - A python plugin finder

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

# This program is distributed 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 General Public License for more details.

# You should have received a copy of the GNU General Public License

# along with this program. If not, see <http://www.gnu.org/licenses/>.

import importlib

import inspect

PATHS = []

def add_path(path):

"""

Adds a path to search for plugins under

"""

global PATHS # pylint:disable-msg=W0602

if not path in PATHS:

PATHS.append(path)

def remove_path(path):

"""

Removes a plugin search path

"""

global PATHS # pylint:disable-msg=W0602

if path in PATHS:

PATHS.remove(path)

def get_paths():

"""

Returns the list of all plugin paths

"""

return PATHS

def find(cls):

"""

Find all plugins that are subclasses of cls in the current search paths

"""

if not inspect.isclass(cls):

raise TypeError('{} is not a class instance')

cls_name = cls.__name__

for path in PATHS:

mod = importlib.import_module(path)

for symbol_name in dir(mod):

if symbol_name == cls_name:

continue

symbol = getattr(mod, symbol_name, None)

if not inspect.isclass(symbol):

continue

if inspect.isabstract(symbol):

continue

yield symbol

__all__ = [add_path, remove_path, get_paths, find]

grim/pyscovery