| # Licensed to the Apache Software Foundation (ASF) under one |
| # or more contributor license agreements. See the NOTICE file |
| # distributed with this work for additional information |
| # regarding copyright ownership. The ASF licenses this file |
| # to you 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 time |
| from threading import Thread |
| |
| |
| class AbstractAsyncScheduledTask: |
| """ |
| Exposes the contract to follow to implement a scheduled task to be executed by the ScheduledExecutor |
| """ |
| |
| def execute_task(self): |
| """ |
| Override this method and implement the task to be executed by the ScheduledExecutor with a specified |
| interval. |
| """ |
| raise NotImplementedError |
| |
| |
| class ScheduledExecutor(Thread): |
| """ |
| Executes a given task with a given interval until being terminated |
| """ |
| |
| def __init__(self, delay, task): |
| """ |
| Creates a ScheduledExecutor thread to handle interval based repeated execution of a given task of type |
| AbstractAsyncScheduledTask |
| :param int delay: The interval to keep between executions |
| :param AbstractAsyncScheduledTask task: The task to be implemented |
| :return: |
| """ |
| |
| Thread.__init__(self) |
| self.delay = delay |
| """ :type : int """ |
| self.task = task |
| """ :type : AbstractAsyncScheduledTask """ |
| self.terminated = False |
| """ :type : bool """ |
| |
| def run(self): |
| """ |
| Start the scheduled task with a sleep time of delay in between |
| :return: |
| """ |
| while not self.terminated: |
| time.sleep(self.delay) |
| if not self.terminated: |
| task_thread = Thread(target=self.task.execute_task) |
| task_thread.start() |
| |
| def terminate(self): |
| """ |
| Terminate the scheduled task. Allow a maximum of 'delay' seconds to be terminated. |
| :return: void |
| """ |
| self.terminated = True |
