config.py 文件源码

def load_paste_app(app_name, flavor=None, conf_file=None):
    """Builds and returns a WSGI app from a paste config file.

    We assume the last config file specified in the supplied ConfigOpts
    object is the paste config file, if conf_file is None.

    :param app_name: name of the application to load
    :param flavor: name of the variant of the application to load
    :param conf_file: path to the paste config file

    :raises: RuntimeError when config file cannot be located or application
            cannot be loaded from config file
    """
    # append the deployment flavor to the application name,
    # in order to identify the appropriate paste pipeline
    app_name += _get_deployment_flavor(flavor)

    if not conf_file:
        conf_file = _get_deployment_config_file()

    logger = logging.getLogger(__name__)
    try:
        logger.debug("Loading %(app_name)s from %(conf_file)s",
                     {'conf_file': conf_file, 'app_name': app_name})

        app = deploy.loadapp("config:%s" % conf_file, name=app_name)

        # Log the options used when starting if we're in debug mode...
        if CONF.debug:
            CONF.log_opt_values(logger, logging.DEBUG)

        return app
    except (LookupError, ImportError) as e:
        msg = (_("Unable to load %(app_name)s from "
                 "configuration file %(conf_file)s."
                 "\nGot: %(e)r") % {'app_name': app_name,
                                    'conf_file': conf_file,
                                    'e': e})
        logger.error(msg)
        raise RuntimeError(msg)