# Copyright 2013 New Dream Network, LLC (DreamHost)
#
#    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 ExecutorBase(object):

    # Executor can override how we run the application callback
    _executor_callback = None

    def __init__(self, conf, listener, dispatcher):
        self.conf = conf
        self.listener = listener
        self.dispatcher = dispatcher

    @abc.abstractmethod
    def start(self):
        """Start polling for incoming messages."""

    @abc.abstractmethod
    def stop(self):
        """Stop polling for messages."""

    @abc.abstractmethod
    def wait(self, timeout=None):
        """Wait until the executor has stopped polling.

        If a timeout is provided, and it is not ``None`` then this method will
        wait up to that amount of time for its components to finish, if not
        all components finish in the alloted time, then false will be returned
        otherwise true will be returned.
        """