for-emit-of

!Node.js CI  

Turn Node.js Events into Async Iterables.

``
$ npm install for-emit-of
`

- Example
- Transform
- Change the event
- Change the end
- Timeout
- firstEventTimeout
- inBetweenTimeout
- Limit
- Debug
- Keep Alive

Example


`javascript
import forEmitOf from 'for-emit-of';
import { Emitter } from '..'; // Example

const iterator = forEmitOf(Emitter, {
event: "data", // Default
});

for await (const event of iterator){
// Do Something
}
`

> Equivalent to

`javascript
Emitter.on("data", () => {});
`

Transform

`javascript
import forEmitOf from 'for-emit-of';
import { Emitter } from '..';

const iterator = forEmitOf(Emitter, {
transform: async (event) => { // async aware
return JSON.stringify(event);
}
});

for await (const event of iterator){
// Stringy
}
`

> Equivalent to

`javascript
Emitter.on("data", (event) => {
const stringy = JSON.stringify(event);
});
`

Change the event


`javascript
import forEmitOf from 'for-emit-of';
import { Cart } from '..';

const iterator = forEmitOf(Cart, {
event: "checkout"
});

for await (const order of iterator){
// Do Something
}
`

> Equivalent to

`javascript
Cart.on("checkout", (order) => { ... });
`

Change the end


`javascript
import forEmitOf from 'for-emit-of';
import { Cart } from '..';

const iterator = forEmitOf(Cart, {
end: ["end", "close"] // default
});
`

Timeout

firstEventTimeout


`javascript
import forEmitOf from 'for-emit-of';
import { EventEmitter } from "events";

const emitter = new EventEmitter();

const iterator = forEmitOf(emitter, {
firstEventTimeout: 1000,
});

setTimeout(() => {
emitter.emit("data", {});
}, 2000); // greater than firstEventTimeout ERROR!

for await (const msg of iterator) {
console.log(msg); // never get here
}
`

inBetweenTimeout


`javascript
import forEmitOf from 'for-emit-of';
import { EventEmitter } from "events";

const emitter = new EventEmitter();

const iterator = forEmitOf(emitter, {
inBetweenTimeout: 1000,
});

setInterval(() => {
emitter.emit("data", {})
}, 2000) // greater than inBetweenTimeout ERROR!

for await (const msg of iterator) {
console.log(msg); // gets here once
}
`

Limit


`js
import forEmitOf from 'for-emit-of';
import { EventEmitter } from "events";

const emitter = new EventEmitter();

const iterator = forEmitOf(emitter, {
limit: 10
});

const interval = setInterval(() => {
emitter.emit("data", {});
}, 100);

let msgCount = 0;

for await (const msg of iterator) {
msgCount += 1
}

clearInterval(interval);

console.log(msgCount); // 10
`

Debug


`ts
import forEmitOf from 'for-emit-of';
import { EventEmitter } from "events";

const emitter = new EventEmitter();

const iterator = forEmitOf(emitter, {
limit: 10,
debug: true // logs
});
`

Keep Alive


`ts
import forEmitOf from 'for-emit-of';
import { EventEmitter } from "events";

const neverEmit = new EventEmitter();

const iterator = forEmitOf(neverEmit, {
keepAlive: 1000
});

for await (const data of iterator){
// waiting ⌛
}
``