| # Copyright 2017 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| import logging |
| import sys |
| import time |
| |
| |
| def AddLoggingArguments(parser): |
| """Adds standard logging flags to the parser. |
| |
| After parsing args, remember to invoke InitializeLogging() with the parsed |
| args, to configure the log level. |
| """ |
| group = parser.add_mutually_exclusive_group() |
| group.add_argument( |
| '-v', '--verbose', action='count', default=0, |
| help='Log more. Use multiple times for even more logging.') |
| group.add_argument( |
| '-q', '--quiet', action='count', default=0, |
| help=('Log less (suppress output). Use multiple times for even less ' |
| 'output.')) |
| |
| |
| def InitializeLogging(args, handler=None): |
| """Initialized the log level based on commandline flags. |
| |
| This expects to be given an "args" object with the options defined by |
| AddLoggingArguments(). |
| """ |
| if args.quiet >= 2: |
| log_level = logging.CRITICAL |
| elif args.quiet == 1: |
| log_level = logging.ERROR |
| elif args.verbose == 0: |
| log_level = logging.WARNING |
| elif args.verbose == 1: |
| log_level = logging.INFO |
| else: |
| log_level = logging.DEBUG |
| logger = logging.getLogger() |
| logger.setLevel(log_level) |
| if not handler: |
| handler = logging.StreamHandler(sys.stdout) |
| handler.setFormatter(CustomFormatter()) |
| logger.addHandler(handler) |
| |
| |
| class CustomFormatter(logging.Formatter): |
| """Custom log formatter.""" |
| |
| # override |
| def __init__(self, fmt='%(threadName)-4s %(message)s'): |
| # Can't use super() because in older Python versions logging.Formatter does |
| # not inherit from object. |
| logging.Formatter.__init__(self, fmt=fmt) |
| self._creation_time = time.time() |
| |
| # override |
| def format(self, record): |
| # Can't use super() because in older Python versions logging.Formatter does |
| # not inherit from object. |
| msg = logging.Formatter.format(self, record) |
| if 'MainThread' in msg[:19]: |
| msg = msg.replace('MainThread', 'Main', 1) |
| timediff = time.time() - self._creation_time |
| return '%s %8.3fs %s' % (record.levelname[0], timediff, msg) |
| |