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    Pythonlanggraph.checkpointserdejsonplusJsonPlusSerializer
    Class●Since v1.0

    JsonPlusSerializer

    Serializer that uses ormsgpack, with optional fallbacks.

    Warning

    Security note: This serializer is intended for use within the BaseCheckpointSaver class and called within the Pregel loop. It should not be used on untrusted python objects. If an attacker can write directly to your checkpoint database, they may be able to trigger code execution when data is deserialized.

    Set the environment variable LANGGRAPH_STRICT_MSGPACK=true to restrict deserialization to a built-in allowlist of safe types. You can also pass an explicit allowed_msgpack_modules to the constructor.

    Copy
    JsonPlusSerializer(
      self,
      *,
      pickle_fallback: bool = False,
      allowed_json_modules: Iterable[tuple[str, ...]] | Literal[True] | None = None,
      allowed_msgpack_modules: AllowedMsgpackModules | Literal[True] | None = _lg_msgpack._SENTINEL,
      __unpack_ext_hook__: Callable[[int, bytes], Any] | None = None
    )

    Bases

    SerializerProtocol

    Used in Docs

    • Persistence

    Constructors

    constructor
    __init__
    NameType
    pickle_fallbackbool
    allowed_json_modulesIterable[tuple[str, ...]] | Literal[True] | None
    allowed_msgpack_modulesAllowedMsgpackModules | Literal[True] | None
    __unpack_ext_hook__Callable[[int, bytes], Any] | None

    Attributes

    attribute
    pickle_fallback: pickle_fallback

    Methods

    method
    with_msgpack_allowlist

    Return a new serializer with a merged msgpack allowlist.

    method
    dumps_typed
    method
    loads_typed
    View source on GitHub