logger.py 文件源码

def __init__(self, filename=None, default_verbose=0):
    """
    Constructs a logger with optional log file output.

    Args:
        filename: optional log file output. If None, nothing will be 
        written to file
    """
    now = datetime.datetime.now()
    self.verbose_thresh = int(os.environ.get('VERBOSE', 0))
    self.default_verbose = default_verbose
    if filename is not None:
      self.filename = filename
      dirname = os.path.dirname(self.filename)
      if not os.path.exists(dirname):
        os.makedirs(dirname)
      open(self.filename, 'w').close()
      self.info('Log written to {}'.format(
          os.path.abspath(self.filename)))
    else:
      self.filename = None