await-event-emitter

Await events library like EventEmitter


Why?

The concept of Webpack plugin has lots of lifecycle hooks, they implement this via EventEmitter.
In the primitive events module on nodejs, the usage as follows

``javascript
const EventEmitter = require('events')
const emitter = new EventEmitter()

emitter
.on('event', () => {
// do something synchronously
})
.emit('event', '...arguments')
`

The listener must be synchronous, that is way i wrote it.
And await-event-emitter support synchronous emitter magically :smile:

Installation

`bash
npm install --save await-event-emitter
`

Usage

`javascript
const AwaitEventEmitter = require('await-event-emitter').default

const emitter = new AwaitEventEmitter()
const tick = () =>
new Promise((resolve) => {
setTimeout(() => {
console.log('tick')
resolve()
}, 1000)
})

emitter.on('event', async () => {
// wait to print
await tick()
})

async function run() {
// NOTE: it's important to await the reset process
await emitter.emit('event', '...arguments')
await emitter.emit('event', 'again')

// support emit it synchronously
emitter.emitSync('event', 'again')
}

run()
`

API

$3

- addListener(event, listener) : AwaitEventEmitter
alias: on
- once(event, listener)
- prependListener(event, listener) : AwaitEventEmitter
alias: prepend
- prependOnceListener(event, listener) : AwaitEventEmitter
alias: prependOnce
- removeListener(event, listener) : AwaitEventEmitter
alias: off
- listeners(event) : []
- emit(event, ...args) : Promise.resolve(boolean)
emit listeners asynchronously, we recommended await it resolved the result
- emitSync(event, ...args) : boolean
emit listeners synchronously

Test

`bash
npm test
`

Contributing

- Fork it!
- Create your new branch:
git checkout -b feature-new or git checkout -b fix-which-bug
- Start your magic work now
- Make sure npm test passes
- Commit your changes:
git commit -am 'feat: some description (close #123)' or git commit -am 'fix: some description (fix #123)'
- Push to the branch: git push`
- Submit a pull request :)

Authors

This library is written and maintained by imcuttle, imcuttle@163.com.

License

MIT - imcuttle 🐟