cliff/cliff/hooks.py

66 lines
1.9 KiB
Python

# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import abc
import six
@six.add_metaclass(abc.ABCMeta)
class CommandHook(object):
"""Base class for command hooks.
:param app: Command instance being invoked
:paramtype app: cliff.command.Command
"""
def __init__(self, command):
self.cmd = command
@abc.abstractmethod
def get_parser(self, parser):
"""Return an :class:`argparse.ArgumentParser`.
:param parser: An existing ArgumentParser instance to be modified.
:paramtype parser: ArgumentParser
:returns: ArgumentParser
"""
return parser
@abc.abstractmethod
def get_epilog(self):
"Return text to add to the command help epilog."
return ''
@abc.abstractmethod
def before(self, parsed_args):
"""Called before the command's take_action() method.
Any return value is ignored.
:param parsed_args: The arguments to the command.
:paramtype parsed_args: argparse.Namespace
"""
@abc.abstractmethod
def after(self, parsed_args, return_code):
"""Called after the command's take_action() method.
Any return value is ignored.
:param parsed_args: The arguments to the command.
:paramtype parsed_args: argparse.Namespace
:param return_code: The value returned from take_action().
:paramtype return_code: int
"""