config.py 文件源码

def load_yaml(cls, filename: str):
        """
        Load a hierarchy of sparse objects from a YAML file.

        :param filename: The filename to open.
        :return: The configuration object hierarchy
        """
        def unpack(mapping, parent=None):
            """
            Recursively create Configuration objects with the parent
            correctly set, returning the top-most parent.
            """
            if mapping is None:
                return None

            children = config = None

            if not isinstance(mapping, cls):
                children = mapping.pop('children', None)
                config = cls(**cls._coerce_types(mapping), parent=parent)

            if children is not None and len(children) > 0:
                for child in children:
                    unpack(child, parent=config)
            return config

        if filename in cls._yaml_cache:
            return cls._yaml_cache[filename]

        data = None
        with open(filename, 'r') as yaml_file:
            data = unpack(yaml.round_trip_load(yaml_file.read()))

        if data is not None:
            cls._yaml_cache[filename] = data

        return data