utility to race a promise with an abort signal
npm install race-abortutility to race a promise with an abort signal. for wrapping non-abortable promises.
``sh`
npm i --save race-abort
#### Supports both ESM and CommonJS
`js
// esm
import raceAbort from 'race-abort
// commonjs
const raceAbort = require('race-abort').default
``
#### Promise wins race against abort
`js
import raceAbort from 'race-abort
import {promises as fs} from 'fs'
async function fooTask(signal) {
const json = await fetch('https://google.com', { signal }).then(res => res.toJSON())
// check if aborted before running task
if (signal.aborted) throw new AbortError()
await raceAbort(signal, fs.writeFile(json.filename, json.body))
}
``
#### Async task race against abort
`js
import raceAbort from 'race-abort
import {promises as fs} from 'fs'
// for node.js import abort-controller
// in browser use AbortController global - https://developer.mozilla.org/en-US/docs/Web/API/AbortController
import AbortController from 'abort-controller'
async function fooTask(signal) {
const json = await fetch('https://google.com', { signal }).then(res => res.toJSON())
await raceAbort(signal, () => fs.writeFile(json.filename, json.body)) // task get's signal as an argument if you need it
}
const controller = new AbortController()
fooTask(controller.signal).then((result) => {
// result is writeFile result
})
``
#### Async task loses against abort
`js
import raceAbort from 'race-abort
import {promises as fs} from 'fs'
// for node.js import abort-controller
// in browser use AbortController global - https://developer.mozilla.org/en-US/docs/Web/API/AbortController
import AbortController from 'abort-controller'
async function fooTask(signal) {
const json = await fetch('https://google.com', { signal }).then(res => res.toJSON())
await raceAbort(signal, () => fs.writeFile(json.filename, json.body)) // task get's signal as an argument if you need it
}
const controller = new AbortController()
controller.abort()
fooTask.catch(err => {
if (err.name === 'AbortError') {
// task aborted via abort signal
}
})
``
#### Note about AbortError and Performance
For performance reasons, AbortError does not extend the Error class and does not have stacks. If you want AbortError to be a real Error use race-abort/raceAbortError
`js
import raceAbortError from 'race-abort/raceAbortError
import {promises as fs} from 'fs'
// for node.js import abort-controller
// in browser use AbortController global - https://developer.mozilla.org/en-US/docs/Web/API/AbortController
import AbortController from 'abort-controller'
async function fooTask(signal) {
const json = await fetch('https://google.com', { signal }).then(res => res.toJSON())
await raceAbort(signal, () => fs.writeFile(json.filename, json.body)) // task get's signal as an argument if you need it
}
const controller = new AbortController()
controller.abort()
fooTask(controller.signal).catch(err => {
if (err.name === 'AbortError') {
console.log(err instanceof Error) // true
// task aborted via abort signal
}
})
```
MIT