useAsyncQueue

Executes each asynchronous task sequentially and passes the current task result to the next task.

Usage

import { useAsyncQueue } from '@vueuse/core'

function p1() {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(1000)
    }, 10)
  })
}

function p2(result: number) {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(1000 + result)
    }, 20)
  })
}

const { activeIndex, result } = useAsyncQueue([p1, p2])

console.log(activeIndex.value) // current pending task index

console.log(result) // the tasks result

Result State

Each task in the result array has a state and data property:

interface UseAsyncQueueResult<T> {
  state: 'aborted' | 'fulfilled' | 'pending' | 'rejected'
  data: T | null
}

Interrupt on Failure

By default, if a task fails, subsequent tasks will not be executed. Set interrupt: false to continue executing even after failures.

const { result } = useAsyncQueue([p1, p2], {
  interrupt: false, // continue even if p1 fails
})

Callbacks

const { result } = useAsyncQueue([p1, p2], {
  onError() {
    console.log('A task failed')
  },
  onFinished() {
    console.log('All tasks completed (or interrupted)')
  },
})

Abort Signal

You can pass an AbortSignal to cancel the queue execution.

const controller = new AbortController()

const { result } = useAsyncQueue([p1, p2], {
  signal: controller.signal,
})

// Later, abort the queue
controller.abort()