TypeScript SDKSteps

Wait for signal

Wait for a particular signal to be received before continuing with step.waitForSignal(). You must resume signals by calling step.sendSignal or client.sendSignal (as a step or on the Inngest client), passing the same signal string and any data you want to inject into the function run.

step.waitForSignal(id, options): Promise<null | EventPayload>

  • Name
    id
    Type
    string
    Required
    required
    Description

    The ID of the step. This will be what appears in your function's logs and is used to memoize step state across function versions.

  • Name
    options
    Type
    object
    Required
    required
    Description

    Options for configuring how to wait for the event.

    Properties
    • Name
      signal
      Type
      string
      Required
      required
      Description

      A unique identifier for the signal, used to resume this function run.

    • Name
      timeout
      Type
      string
      Required
      required
      Description

      The amount of time to wait to receive the signal. A time string compatible with the ms package, e.g. "30m", "3 hours", or "2.5d".

      If the signal is not received before this timeout, the run will resume with an undefined return value.

    • Name
      onConflict
      Type
      'fail' | 'replace'
      Required
      optional
      Description

      How to handle duplicate signals. By default, step.waitForSignal requires a unique signal and duplicate signals will fail the function.

      Set to 'replace' to replace any other run's signal. Note that previous runs will NOT resume from this signal if replaced, and instead will time out.

      To resume many runs from a single signal, use step.waitForEvent.

// Wait 15m for an approval
const approval = await step.Signal("wait-for-approval", {
  signal: "task/71651db4-9f27-466a-a6be-4759b9784b3c",
  timeout: "7d",
});

step.waitForSignal() must be called using await or some other Promise handler to ensure your function pauses correctly.

step.waitForSignal() must be resumed by inngest.sendSignal, step.sendSignal, or a call to the signal API to be resumed with a matching signal string.