Synnefo » snf-ganeti » ganeti-local

class LogFileHandler(logging.FileHandler):

  """Log handler that doesn't fallback to stderr.

  When an error occurs while writing on the logfile, logging.FileHandler tries

  to log on stderr. This doesn't work in ganeti since stderr is redirected to

  the logfile. This class avoids failures reporting errors to /dev/console.

  """

  def __init__(self, filename, mode="a", encoding=None):

    """Open the specified file and use it as the stream for logging.

    Also open /dev/console to report errors while logging.

    """

    logging.FileHandler.__init__(self, filename, mode, encoding)

    self.console = open(constants.DEV_CONSOLE, "a")

  def handleError(self, record):

    """Handle errors which occur during an emit() call.

    Try to handle errors with FileHandler method, if it fails write to

    /dev/console.

    """

    try:

      logging.Filehandler.handleError(self, record)

    except Exception:

      try:

        self.console.write("Cannot log message:\n%s\n" % self.format(record))

      except Exception:

        # Log handler tried everything it could, now just give up

        pass