import json
import logging.config
import os


def setup_logging():
    """
    set up logging using the configured filename

    if LOGGING_CONFIG is defined in the environment, use this for
    the filename, otherwise use logging_default_config.json
    """
    default_filename = os.path.join(
        os.path.dirname(__file__), 'logging_default_config.json')
    filename = os.getenv('LOGGING_CONFIG', default_filename)
    with open(filename) as f:
        # TODO: this mac workaround should be removed ...
        d = json.loads(f.read())
        import platform
        if platform.system() == 'Darwin':
            d['handlers']['syslog_handler']['address'] = '/var/run/syslog'
        logging.config.dictConfig(d)
        # logging.config.dictConfig(json.loads(f.read()))