Logs all extra args

logging_extra_formatter.py

import logging

class ExtraFormatter(logging.Formatter):
    defs = set(logging.LogRecord(None, None, None, None, None, None, None).__dict__.keys())

    def format(self, record):
        extra = set(record.__dict__.keys()) - self.defs

        if extra:
            # Override message with extra info
            record.msg = "{} {}".format(
                self._join_extra(record, extra),
                record.msg
            )
        return super(TributeExtraFormatter, self).format(record)

    @staticmethod
    def _join_extra(record, extra):
        return ' '.join(['{}={}'.format(key, getattr(record, key)) for key in extra])