https://caolan.github.io/async/

Async utilities for node and the browser
https://caolan.github.io/async/

async callbacks javascript

Last synced: about 1 month ago
JSON representation

Async utilities for node and the browser

• Host: GitHub
• URL: https://caolan.github.io/async/
• Owner: caolan
• License: mit
• Created: 2010-06-01T21:01:30.000Z (over 14 years ago)
• Default Branch: master
• Last Pushed: 2024-11-01T15:36:26.000Z (about 2 months ago)
• Last Synced: 2024-11-10T23:00:27.936Z (about 1 month ago)
• Topics: async, callbacks, javascript
• Language: JavaScript
• Homepage: http://caolan.github.io/async/
• Size: 7.68 MB
• Stars: 28,185
• Watchers: 659
• Forks: 2,407
• Open Issues: 11
• Metadata Files:
  • Readme: README.es.md
  • Changelog: CHANGELOG.md
  • License: LICENSE
  • Support: support/aliases.txt

Awesome Lists containing this project

• Awesome-NodeJS - Async - Utility module provides convinent Async operations (Frameworks)

README

        
![Async Logo](https://raw.githubusercontent.com/caolan/async/master/logo/async-logo_readme.jpg)

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Async is a utility module which provides straight-forward, powerful functions for working with [asynchronous JavaScript](http://caolan.github.io/async/global.html). Although originally designed for use with [Node.js](https://nodejs.org/) and installable via `npm install --save async`, it can also be used directly in the browser.

This version of the package is optimized for building with webpack. If you use Async in Node.js, install [`async`](https://www.npmjs.com/package/async) instead.

For Documentation, visit 

*For Async v1.5.x documentation, go [HERE](https://github.com/caolan/async/blob/v1.5.2/README.md)*

```javascript

// for use with callbacks...

import { forEachOf } from "async-es";

const images = {cat: "/cat.png", dog: "/dog.png", duck: "/duck.png"};

const sizes = {};

forEachOf(images, (value, key, callback) => {

    const imageElem = new Image();

    imageElem.src = value;

    imageElem.addEventListener("load", () => {

        sizes[key] = {

            width: imageElem.naturalWidth,

            height: imageElem.naturalHeight,

        };

        callback();

    });

    imageElem.addEventListener("error", (e) => {

        callback(e);

    });

}, err => {

    if (err) console.error(err.message);

    // `sizes` is now a map of image sizes

    doSomethingWith(sizes);

});

```

```javascript

import { mapLimit } from "async-es";

// ...or ES2017 async functions

mapLimit(urls, 5, async function(url) {

    const response = await fetch(url)

    return response.body

}, (err, results) => {

    if (err) throw err

    // results is now an array of the response bodies

    console.log(results)

})

```