| #!/usr/bin/env python |
| # |
| # Copyright 2018 - The Android Open Source Project |
| # |
| # 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. |
| """Base setup subtask runner. |
| |
| BaseTaskRunner defines basic methods which will be called in the setup process. |
| |
| the flow in each child task runner will be in below manner: |
| Check ShouldRun() -> PrintWelcomMessage() -> _Run() |
| """ |
| |
| from __future__ import print_function |
| import logging |
| import os |
| import textwrap |
| |
| |
| logger = logging.getLogger(__name__) |
| _PARAGRAPH_BREAK = "=" |
| |
| |
| class BaseTaskRunner(object): |
| """A basic task runner class for setup cmd.""" |
| |
| # WELCOME_MESSAGE and WELCOME_MESSAGE_TITLE should both be defined as |
| # strings. |
| WELCOME_MESSAGE = None |
| WELCOME_MESSAGE_TITLE = None |
| |
| def PrintWelcomeMessage(self): |
| """Print out the welcome message in a fancy format. |
| |
| This method will print out the welcome message in the following manner |
| given the following example: |
| e.g. |
| WELCOME_MESSAGE_TITLE = "title" |
| WELCOME_MESSAGE = ( |
| "this is one long str " |
| "broken into multiple lines " |
| "based on the screen width" |
| ) |
| |
| actual output will be: |
| =========================== |
| [title] |
| this is one long str |
| broken into multiple lines |
| based on the screen width |
| =========================== |
| """ |
| if not self.WELCOME_MESSAGE and not self.WELCOME_MESSAGE_TITLE: |
| logger.debug("No welcome message for %s", self.__class__.__name__) |
| return |
| |
| # define the layout of message. |
| console_width = int(os.popen('stty size', 'r').read().split()[1]) |
| break_width = int(console_width / 2) |
| |
| # start to print welcome message. |
| print("\n" +_PARAGRAPH_BREAK * break_width) |
| print(" [%s] " % self.WELCOME_MESSAGE_TITLE) |
| print(textwrap.fill( |
| self.WELCOME_MESSAGE, |
| break_width - 2, |
| initial_indent=" ", |
| subsequent_indent=" ")) |
| print(_PARAGRAPH_BREAK * break_width + "\n") |
| |
| # pylint: disable=no-self-use |
| def ShouldRun(self): |
| """Check if setup should run. |
| |
| Returns: |
| Boolean, True if setup should run False otherwise. |
| """ |
| return True |
| |
| def Run(self, force_setup=False): |
| """Main entry point to the task runner. |
| |
| Args: |
| force_setup: Boolean, True to force execute Run method no matter |
| the result of ShoudRun. |
| """ |
| if self.ShouldRun() or force_setup: |
| self.PrintWelcomeMessage() |
| self._Run() |
| else: |
| logger.info("Skipping setup step: %s", self.__class__.__name__) |
| |
| def _Run(self): |
| """run the setup procedure.""" |
| raise NotImplementedError() |