Add --log-level alias to ros2 log watch

[sloretz]

ros2 component uses --log-level to specify the log severity level, whereas ros2 log watch uses --level.

Modify ros2log/ros2log/verb/watch.py to accept --log-level as an alias for --level:

• ros2log/ros2log/verb/watch.py

Example: How to add the alias

Keep '--level' first (so args.level continues to work without changing the rest of the file) and add '--log-level':

# Before:
parser.add_argument(
    '--level',
    choices=['DEBUG', 'INFO', 'WARN', 'ERROR', 'FATAL',
             'debug', 'info', 'warn', 'error', 'fatal'],
    help='Show only logs at or above the specified severity level')

# After:
parser.add_argument(
    '--level', '--log-level',
    choices=['DEBUG', 'INFO', 'WARN', 'ERROR', 'FATAL',
             'debug', 'info', 'warn', 'error', 'fatal'],
    help='Show only logs at or above the specified severity level')

Example: How to add a test

Add a test in ros2log/test/test_watch.py to verify that --log-level populates args.level:

import argparse
from ros2log.verb.watch import WatchVerb


def test_watch_log_level_alias():
    parser = argparse.ArgumentParser()
    verb = WatchVerb()
    verb.add_arguments(parser, 'ros2 log watch')
    args = parser.parse_args(['--log-level', 'WARN'])
    assert args.level == 'WARN'

[IdiotCoffee]

Hi, I would like to take up this issue - I will add tests and add the log level alias.