#!/usr/bin/env python
# -*- coding: utf-8 -*-

""" An example of using JSON for log configuration """

from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
from __future__ import absolute_import


import json
import logging
import logging.config


def main():
    # each time we need to log something we can create a logger object
    # The operation of creating a logger should be quite cheap.
    # getLogger() without arguments returns the "root" logger.
    logger = logging.getLogger()
    logger.info("This is an INFO message on the root logger.")

    # If we need to separate things, we can always create child loggers:
    child = logging.getLogger().getChild("child")
    child.warning("This is a WARNING message on the child logger.")

    # let's create an error. This will send an email
    child.error("This is an ERROR message.")


if __name__ == "__main__":
    # create an initial logger. It will only log to console and it will disabled
    # when we read the logging configuration from the config file.
    # This logger can be useful when we need early logging. E.g. we may want to log
    # the location of the JSON file (e.g. if we get it from a CLI argument).
    logging.basicConfig(level="INFO")
    logger = logging.getLogger()
    logger.info("This is the logger configured by `logging.basicConfig()`.")

    # set up proper logging. This one disables the previously configured loggers.
    with open("logging.json", "r", encoding="utf-8") as fd:
        logging.config.dictConfig(json.load(fd))

    main()