LangChain Reference home pageLangChain ReferenceLangChain Reference
  • GitHub
  • Main Docs
Deep Agents
LangChain
LangGraph
Integrations
LangSmith
  • Overview
    • Overview
    • Graphs
    • Functional API
    • Pregel
    • Checkpointing
    • Storage
    • Caching
    • Types
    • Runtime
    • Config
    • Errors
    • Constants
    • Channels
    • Agents
    LangGraph CLI
    LangGraph SDK
    LangGraph Supervisor
    LangGraph Swarm
    ⌘I

    LangChain Assistant

    Ask a question to get started

    Enter to send•Shift+Enter new line

    Menu

    OverviewGraphsFunctional APIPregelCheckpointingStorageCachingTypesRuntimeConfigErrorsConstantsChannelsAgents
    LangGraph CLI
    LangGraph SDK
    LangGraph Supervisor
    LangGraph Swarm
    Language
    Theme
    Pythonlanggraphpregel_algoapply_writes
    Function●Since v0.6

    apply_writes

    Apply writes from a set of tasks (usually the tasks from a Pregel step) to the checkpoint and channels, and return managed values writes to be applied externally.

    Copy
    apply_writes(
      checkpoint: Checkpoint,
      channels: Mapping[str, BaseChannel],
      tasks: Iterable[WritesProtocol],
      get_next_version: GetNextVersion | None,
      trigger_to_nodes: Mapping[str, Sequence[str]]
    ) -> set[str]

    Parameters

    NameTypeDescription
    checkpoint*Checkpoint

    The checkpoint to update.

    channels*Mapping[str, BaseChannel]

    The channels to update.

    tasks*Iterable[WritesProtocol]

    The tasks to apply writes from.

    get_next_version*GetNextVersion | None

    Optional function to determine the next version of a channel.

    trigger_to_nodes*Mapping[str, Sequence[str]]

    Mapping of channel names to the set of nodes that can be triggered by updates to that channel.

    View source on GitHub