qiankun（乾坤）

In Chinese traditional culture qian means heaven and kun stands for earth, so qiankun is the universe.

An implementation of Micro Frontends, based on single-spa, but made it production-ready.

🤔 Motivation

As we know what micro-frontends aims for:

Techniques, strategies and recipes for building a modern web app with multiple teams using different JavaScript frameworks. — Micro Frontends

An independent development experience is very important for a large system, especially with an enterprise application. But if you've tried to implement a micro-frontends architecture in such a system, you'll usually hurt your brain with such problems:

• How to compose your independent sub apps into your main system?
• How to guarantee your sub apps to be isolated by each other?
• and so on...

We built an library to help you solve these glitch problems automatically without any mental burden of yours, then named it qiankun.

Probably the most complete micro-frontends solution you ever met🧐.

📦 Installation

$ yarn add qiankun  # or npm i qiankun -S

🔨 Getting Started

1. Create master framework with qiankun

import { registerMicroApps, start } from 'qiankun';

function render({ appContent, loading }) {
  const container = document.getElementById('container');
  ReactDOM.render(<Framework loading={loading} content={appContent} />, container);
}

function genActiveRule(routerPrefix) {
  return location => location.pathname.startsWith(routerPrefix);
}

registerMicroApps([
  {
    name: 'react app', // app name registered
    entry: '//localhost:7100',
    render,
    activeRule: genActiveRule('/react'),
  },
  {
    name: 'vue app',
    entry: { scripts: ['//localhost:7100/main.js'] },
    render,
    activeRule: genActiveRule('/vue'),
  },
]);

start();

2. Export the lifecycles from your sub app entry

export async function bootstrap() {
  console.log('react app bootstraped');
}

export async function mount(props) {
  console.log(props);
  ReactDOM.render(<App />, document.getElementById('react15Root'));
}

export async function unmount() {
  ReactDOM.unmountComponentAtNode(document.getElementById('react15Root'));
}

For more lifecycle information, see single-spa lifecycles

3. Config your sub app bundler

While you wanna build a sub app to integrate to qiankun, pls make sure your bundler have the required configuration below:

webpack:

const packageName = require('./package.json').name;

module.exports = {
  output: {
    library: `${packageName}-[name]`,
    libraryTarget: 'umd',
    jsonpFunction: `webpackJsonp_${packageName}`,
  },
};

see https://webpack.js.org/configuration/output/#outputlibrary

parcel:

parcel serve entry.js --global myvariable

see https://en.parceljs.org/cli.html#expose-modules-as-umd

💿 Examples

$yarn
$yarn install:examples
$yarn start

Visit http://localhost:7099

:sparkles: Features

• Based on single-spa
• HTML Entry
• Config Entry
• Isolated styles
• JS Sandbox
• Assets Prefetch
• @umijs/plugin-qiankun integration

📖 API

registerMicroApps(apps: Array<RegistrableApp<T>>, lifeCycles?: LifeCycles<T>, opts?: RegisterMicroAppsOpts)

function registerMicroApps<T extends object = {}>(
  apps: Array<RegistrableApp<T>>,
  lifeCycles?: LifeCycles<T>,
  opts?: RegisterMicroAppsOpts,
): void;

type RegistrableApp = {
  // name to identify your app
  name: string;
  // where your sub app served from, supported html entry and config entry
  entry: string | { scripts?: string[]; styles?: string[]; html?: string };
  // render function called around sub app lifecycle
  render: (props?: { appContent: string; loading: boolean }) => any;
  // when sub app active
  activeRule: (location: Location) => boolean;
  // props pass through to sub app
  props?: object;
};

type Lifecycle<T extends object> = (app: RegistrableApp<T>) => Promise<any>;
type LifeCycles<T extends object> = {
  beforeLoad?: Lifecycle<T> | Array<Lifecycle<T>>;
  beforeMount?: Lifecycle<T> | Array<Lifecycle<T>>;
  afterMount?: Lifecycle<T> | Array<Lifecycle<T>>;
  beforeUnmount?: Lifecycle<T> | Array<Lifecycle<T>>;
  afterUnmount?: Lifecycle<T> | Array<Lifecycle<T>>;
};

start(options: Options): void

function start(options: Options): void;

Options

| param | description | default | | --- | --- | --- | | prefetch | Whether to prefetch assets of sub apps after first sub app mounted | true | | jsSandbox | While sandbox enabled, we could guarantee that sub apps is isolated with each others | true | | singular | Only one sub app display at one runtime, that means a sub app will wait to mount until the before one unmounted | true | | fetch | Set a custom fetch function | window.fetch |

setDefaultMountApp

Set which sub app shoule be active by default after master loaded.

function setDefaultMountApp(defaultAppLink: string): void;

runAfterFirstMounted

function runAfterFirstMounted(effect: () => void): void;

🎯 Roadmap

• [ ] Parcel apps integration (multiple sub apps displayed at the same time, but only one uses router at most)
• [ ] Communication development kits between master and sub apps
• [ ] Custom side effects hijacker
• [ ] Nested Microfrontends

❓ FAQ

https://github.com/umijs/qiankun/wiki/FAQ

👬 Community

https://github.com/umijs/umi#community

or

🎁 Acknowledgements

• single-spa What an awesome meta-framework for micro-frontends!