python-dockerflow provides a :class:`~dockerflow.logging.JsonLogFormatter` Python logging formatter that produces messages following the JSON schema for a common application logging format defined by the illustrious Mozilla Cloud Services group.

.. seealso::

    For more information see the :doc:`API documentation <api/logging>` for the
    ``dockerflow.logging`` module.

There a different ways to configure Python logging, please refer to the :mod:`logging` documentation to learn more.

The following examples should be considered excerpts and won't be enough for your application to work. They only illustrate how to use the JSON logging formatter for a specific logger.

A simple example configuration for a myproject logger could look like this:

import logging.config

cfg = {
    'version': 1,
    'formatters': {
        'json': {
            '()': 'dockerflow.logging.JsonLogFormatter',
            'logger_name': 'myproject'
        }
    },
    'handlers': {
        'console': {
            'level': 'DEBUG',
            'class': 'logging.StreamHandler',
            'formatter': 'json'
        },
    },
    'loggers': {
        'myproject': {
            'handlers': ['console'],
            'level': 'DEBUG',
        },
    }
}

logging.config.dictConfig(cfg)
logger = logging.getLogger('myproject')
logger.info('I am logging in mozlog format now! woo hoo!')

In this example, we set up a logger for myproject (you'd replace that with your project name) which has a single handler named console which uses the mozlog formatter to output log event data to stdout.

Consider an ini file with the following content that does the same thing as the dictionary based configuratio above:

 [loggers]
 keys = root, myproject

 [handlers]
 keys = console

 [formatters]
 keys = json

 [logger_root]
 level = INFO
 handlers = console

 [logger_myproject]
 level = DEBUG
 handlers = console
 qualname = myproject

 [handler_console]
 class = StreamHandler
 level = DEBUG
 args = (sys.stdout,)
 formatter = json

 [formatter_json]
 class = dockerflow.logging.JsonLogFormatter

Then load the ini file using the :mod:`logging` module function :func:`logging.config.fileConfig`:

 logging.config.fileConfig('logging.ini')
 logger = logging.getLogger('myproject')
 logger.info('I am logging in mozlog format now! woo hoo!')