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Run.observeStreamVNext() (Experimental)

The .observeStreamVNext() method opens a new ReadableStream to a workflow run that is currently running, allowing you to observe the stream of events if the original stream is no longer available.

Usage exampleDirect link to Usage example

const run = await workflow.createRunAsync();

run.streamVNext({
inputData: {
value: "initial data",
},
});

const stream = await run.observeStreamVNext();

for await (const chunk of stream) {
console.log(chunk);
}

ReturnsDirect link to Returns

ReadableStream<ChunkType>

Stream EventsDirect link to Stream Events

The stream emits various event types during workflow execution. Each event has a type field and a payload containing relevant data:

  • workflow-start: Workflow execution begins
  • workflow-step-start: A step begins execution
  • workflow-step-output: Custom output from a step
  • workflow-step-result: A step completes with results
  • workflow-finish: Workflow execution completes with usage statistics

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