Graylog JSON formatter

GrayLogJSONFormatter formatted LogRecord as JSON object for graylog JSON extractor. JSON object include LogRecord attributes as default_keys and include extra attributes: source, message, asctime and data.

Example

configure:

from logging import config

config.dictConfig({
        'version': 1,
        'disable_existing_loggers': True,
        'formatters': {
            'graylog': {
                '()': 'graylog_json_formatter.GrayLogJSONFormatter',
                'format': '({levelname}) | {name} | [{asctime}]: '
                          'File {pathname}:{lineno}" - {funcName}() | {message}',
                'style': '{',
                'source': 'test',
                'environment': 'testing',
                'keys': {
                    'name', 'levelno', 'levelname',
                    'pathname', 'filename', 'module', 'lineno', 'funcName',
                    'created', 'asctime', 'msecs', 'relativeCreated',
                    'thread', 'threadName', 'process',
                    'message', 'data',
                    'exc_text', 'stack_info',
                },
                'extra': {'service': 'my-service'},
            }
        },
        'handlers': {
            'console': {
                'level': 'DEBUG',
                'class': 'logging.StreamHandler',
                'formatter': 'graylog',
            },
            'graylog': {
                'level': 'DEBUG',
                'class': 'logging.handlers.SysLogHandler',
                'formatter': 'graylog',
                'address': ('localhost', 10000),
            }
        },
        'loggers': {
            'test': {
                'level': 'DEBUG',
                'handlers': ['console', 'graylog'],
                'propagate': False,
            },
        }
    })

    logger = logging.getLogger('test')

logging:

# extra usage
logger.debug('test message: % | %s', 1, 2, extra={'data': {'key': 'value', 'int_key': 12})

Graylog extract extra as data-key and data-int_key fields.

extra argument may be callable or string with dotted path to callable attribute:

'extra': lambda record: {'service': 'service-func'}