Python logging 模块，_levelToName() 实例源码

def make_logging_level_names_consistent():
    """Rename the standard library's logging levels to match Twisted's.

    Twisted's new logging system in `twisted.logger` that is.
    """
    for level in list(logging._levelToName):
        if level == logging.NOTSET:
            # When the logging level is not known in Twisted it's rendered as
            # a hyphen. This is not a common occurrence with `logging` but we
            # cater for it anyway.
            name = "-"
        elif level == logging.WARNING:
            # "Warning" is more consistent with the other level names than
            # "warn", so there is a fault in Twisted here. However it's easier
            # to change the `logging` module to match Twisted than vice-versa.
            name = "warn"
        else:
            # Twisted's level names are all lower-case.
            name = logging.getLevelName(level).lower()
        # For a preexisting level this will _replace_ the name.
        logging.addLevelName(level, name)

def get_stdout_levelname():
    """Return the log levelname."""
    return logging._levelToName[stdout_logger.level]

def cli(ctx, manager, output_format, stats, stop_on_error):
    """ CLI for multi-package manager upgrades. """
    level = logger.level
    try:
        level_to_name = logging._levelToName
    # Fallback to pre-Python 3.4 internals.
    except AttributeError:
        level_to_name = logging._levelNames
    level_name = level_to_name.get(level, level)
    logger.debug('Verbosity set to {}.'.format(level_name))

    # Print help screen and exit if no sub-commands provided.
    if ctx.invoked_subcommand is None:
        click.echo(ctx.get_help())
        ctx.exit()

    # Filters out the subset of managers selected by the user.
    target_managers = [
        m for mid, m in pool().items()
        if mid in set(manager)] if manager else pool().values()

    # Apply manager-level option to either raise on error or not.
    for m in target_managers:
        m.raise_on_error = stop_on_error

    # Pre-filters inactive managers.
    def keep_available(manager):
        if manager.available:
            return True
        logger.warning('Skip unavailable {} manager.'.format(manager.id))
    # Use an iterator to not trigger log messages for subcommands not using
    # this variable.
    active_managers = ifilter(keep_available, target_managers)

    # Silence all log message for JSON rendering unless in debug mode.
    rendering = RENDERING_MODES[output_format]
    if rendering == 'json' and level_name != 'DEBUG':
        logger.setLevel(logging.CRITICAL * 2)

    # Load up global options to the context.
    ctx.obj = {
        'target_managers': target_managers,
        'active_managers': active_managers,
        'rendering': rendering,
        'stats': stats}

def logger():
    getpid_patch = patch('logging.os.getpid', return_value=111)
    getpid_patch.start()
    time_patch = patch('logging.time.time', return_value=946725071.111111)
    time_patch.start()
    localzone_patch = patch('rfc5424logging.handler.get_localzone', return_value=timezone)
    localzone_patch.start()
    hostname_patch = patch('rfc5424logging.handler.socket.gethostname', return_value="testhostname")
    hostname_patch.start()
    connect_patch = patch('logging.handlers.socket.socket.connect', side_effect=connect_mock)
    connect_patch.start()
    sendall_patch = patch('logging.handlers.socket.socket.sendall', side_effect=connect_mock)
    sendall_patch.start()

    if '_levelNames' in logging.__dict__:
        # Python 2.7
        level_patch = patch.dict(logging._levelNames)
        level_patch.start()
    else:
        # Python 3.x
        level_patch1 = patch.dict(logging._levelToName)
        level_patch1.start()
        level_patch2 = patch.dict(logging._nameToLevel)
        level_patch2.start()

    logging.raiseExceptions = True
    logger = logging.getLogger()
    logger.setLevel(logging.DEBUG)
    yield logger

    getpid_patch.stop()
    time_patch.stop()
    localzone_patch.stop()
    hostname_patch.stop()
    connect_patch.stop()
    sendall_patch.stop()

    if '_levelNames' in logging.__dict__:
        # Python 2.7
        level_patch.stop()
    else:
        # Python 3.x
        level_patch1.stop()
        level_patch2.stop()

    Rfc5424SysLogAdapter._extra_levels_enabled = False