Class Output

pywebio/io_ctrl.py:34–165

``put_xxx()`` 类函数的返回值 若 ``put_xxx()`` 调用的返回值没有被变量接收，则直接将消息发送到会话； 否则消息则作为其他消息的一部分

class Output:
    """ ``put_xxx()`` 类函数的返回值

    若 ``put_xxx()`` 调用的返回值没有被变量接收，则直接将消息发送到会话；
    否则消息则作为其他消息的一部分
    """

    @staticmethod
    def json_encoder(obj, ignore_error=False):
        """json序列化与输出相关消息的Encoder函数 """
        if isinstance(obj, Output):
            return obj.embed_data()
        elif isinstance(obj, OutputList):
            return obj.data

        if not ignore_error:
            raise TypeError('Object of type  %s is not JSON serializable' % obj.__class__.__name__)

    @classmethod
    def dump_dict(cls, data):
        # todo 使用其他方式来转换spec
        return json.loads(json.dumps(data, default=cls.json_encoder))

    @classmethod
    def safely_destruct(cls, obj):
        """安全销毁 OutputReturn 对象/包含OutputReturn对象的dict/list, 使 OutputReturn.__del__ 不进行任何操作"""
        try:
            json.dumps(obj, default=partial(cls.json_encoder, ignore_error=True))
        except Exception:
            pass

    def __init__(self, spec, on_embed=None):
        self.processed = False
        self.on_embed = on_embed or (lambda d: d)
        try:
            self.spec = type(self).dump_dict(spec)  # this may raise TypeError
        except TypeError:
            self.processed = True
            type(self).safely_destruct(spec)
            raise

        # For Context manager
        self.enabled_context_manager = False
        self.container_selector = None
        self.container_dom_id = None  # todo: this name is ambiguous, rename it to `scope_name` or others
        self.after_exit = None

        # Try to make sure current session exist.
        # If we leave the session interaction in `Output.__del__`,
        # the Exception raised from there will be ignored by python interpreter,
        # thus we can't end some session in some cases.
        # See also: https://github.com/pywebio/PyWebIO/issues/243
        get_current_session()

    def enable_context_manager(self, container_selector=None, container_dom_id=None, after_exit=None):
        self.enabled_context_manager = True
        self.container_selector = container_selector
        self.container_dom_id = container_dom_id