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Web Channels Pregel Prebuilt Remote Stream

Client Auth React Logging React Ui Server

LangGraph Checkpoint

LangGraph Checkpoint MongoDB

LangGraph Checkpoint Postgres

LangGraph Checkpoint Redis

LangGraph Checkpoint SQLite

LangGraph Checkpoint Validation

LangGraph Supervisor

LangGraph Swarm

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JavaScript@langchain/langgraphstreamEventLogfail

Method●Since v1.5

fail

Mark the channel as failed after all buffered items are consumed.

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fail(err: unknown)

Parameters

Name	Type	Description
`err`*	`unknown`

View source on GitHub