Parse raw log lines and convert it to a dictionary with extracted features.

def _extract_line_features(self):
        """
        Parse raw log lines and convert it to a dictionary with extracted features.
        """
        for line in self.line_iterator:
            m = COMPILED_AUTH_LOG_REGEX.match(line)

            data = {
                'raw': line
            }

            if m:
                data.update({
                    'timestamp': self._to_epoch(m.group(1)),
                    'hostname': m.group(2),
                    'program': m.group(3),
                    'processid': m.group(4),
                    'message': m.group(5),
                })

            self.parsed_lines.append(data)