app.py 文件源码

def _get_config(key, default_value=None, required=False):
    """
    Gets config from environment variables
    Will return default_value if key is not in environment variables
    :param key: the key of the env variable you are looking for
    :param default_value: value to return if key not in os.environ.
    :param required: if true and key is not set, will raise InvalidConfigException
    :return: os.environ[key] if key in os.environ els default_value
    :exception InvalidConfigException - raised when a required config key is not properly set
    """
    if required and key not in os.environ:
        raise InvalidConfigException("Invalid ENV variable. Please check {0}".format(key))
    to_return = os.environ.get(key, default_value)
    if isinstance(to_return, basestring):
        try:
            to_return = _string_to_bool(to_return)
        except NonBooleanStringException:
            pass
    os.environ[key] = str(to_return)
    return to_return