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Class: Trigger<T>

workflow.Trigger

A PromiseLike helper which exposes its resolve and reject methods.

Trigger is CancellationScope-aware: it is linked to the current scope on construction and throws when that scope is cancelled.

Useful for e.g. waiting for unblocking a Workflow from a Signal.

Example

import { defineSignal, setHandler, sleep, Trigger } from '@temporalio/workflow';

const completeUserInteraction = defineSignal('completeUserInteraction');

export async function waitOnUser(userId: string): Promise<void> {
  const userInteraction = new Trigger<boolean>();

  // programmatically resolve Trigger
  setHandler(completeUserInteraction, () => userInteraction.resolve(true));

  const userInteracted = await Promise.race([userInteraction, sleep('30 days')]);
  if (!userInteracted) {
    await sendReminderEmail(userId);
  }
}

Type parameters​

Name
T

Implements​

  • PromiseLike<T>

Constructors​

constructor​

• new Trigger<T>(): Trigger<T>

Type parameters​

Name
T

Returns​

Trigger<T>

Properties​

reject​

• Readonly reject: (reason?: any) => void

Type declaration​

▸ (reason?): void

Parameters​
NameType
reason?any
Returns​

void

resolve​

• Readonly resolve: (value: T | PromiseLike<T>) => void

Type declaration​

▸ (value): void

Parameters​
NameType
valueT | PromiseLike<T>
Returns​

void

Methods​

then​

▸ then<TResult1, TResult2>(onfulfilled?, onrejected?): PromiseLike<TResult1 | TResult2>

Type parameters​

NameType
TResult1T
TResult2never

Parameters​

NameType
onfulfilled?null | (value: T) => TResult1 | PromiseLike<TResult1>
onrejected?null | (reason: any) => TResult2 | PromiseLike<TResult2>

Returns​

PromiseLike<TResult1 | TResult2>

Implementation of​

PromiseLike.then