app.py 文件源码

def log_to_file(filename, level=INFO, formatter=_LOG_FORMATTER,
                filemode=APPEND, handler=logging.FileHandler):
    """Setup logging or set logging level to file.

    Args:
        filename:  string of path/file to write logs
        level:  a logging level, like logging.INFO
        formatter:  a logging.Formatter object
        filemode:  a mode of writing, like app.APPEND or app.CLOBBER
        handler:  logging.FileHandler (this argument is for testing)
    """
    global _FILE_HANDLER
    _level = get_loglevel(level)
    if type(_FILE_HANDLER) is handler:
        _FILE_HANDLER.setLevel(_level)
    else:
        _FILE_HANDLER = handler(filename=filename, mode=filemode)
        _FILE_HANDLER.setLevel(_level)
        _FILE_HANDLER.setFormatter(formatter)
        logging.getLogger('').addHandler(_FILE_HANDLER)
    logging.info('Logging to file %s [mode=\'%s\', level=%s]',
                 os.path.abspath(filename), filemode,
                 logging.getLevelName(_level))