ngx-planet

A powerful, reliable, fully-featured and production ready Micro Frontend library for Angular.

APIs consistent with angular style, currently only supports Angular, other frameworks are not supported.

English | 中文文档

✨ Features

• Rendering multiple applications at the same time
• Support two mode, coexist and default that switch to another app and destroy active apps
• Support application preload
• Support style isolation
• Built-in communication between multiple applications
• Cross application component rendering
• Comprehensive examples include routing configuration, lazy loading and all features

📖 Documentation

• Introduce
• Getting Started
• Development and Build
• Data shared and Communication
• Cross Application Component rendering
• API References

Alternatives

• single-spa: A javascript front-end framework supports any frameworks.
• mooa: A independent-deployment micro-frontend Framework for Angular from single-spa, planet is very similar to it, but planet is more powerful, reliable, productively and more angular.

Installation

$ npm i @worktile/planet --save
// or
$ yarn add @worktile/planet

Demo

Try out our live demo

Usage

1. Loading NgxPlanetModule in the portal's AppModule

import { NgxPlanetModule } from '@worktile/planet';

@NgModule({
  imports: [
    CommonModule,
    NgxPlanetModule
  ]
})
class AppModule {}

2. Register applications to planet use PlanetService in portal app

@Component({
    selector: 'app-portal-root',
    template: `
        <nav>
            <a [routerLink]="['/app1']" routerLinkActive="active">应用1</a>
            <a [routerLink]="['/app2']" routerLinkActive="active">应用2</a>
        </nav>
        <router-outlet></router-outlet>
        <div id="app-host-container"></div>
        <div *ngIf="!loadingDone">加载中...</div>
    `
})
export class AppComponent implements OnInit {
    title = 'ngx-planet';

    get loadingDone() {
        return this.planet.loadingDone;
    }

    constructor(
        private planet: Planet
    ) {}

    ngOnInit() {
        this.planet.setOptions({
            switchMode: SwitchModes.coexist,
            errorHandler: error => {
                console.error(`Failed to load resource, error:`, error);
            }
        });

        this.planet.registerApps([
            {
                name: 'app1',
                hostParent: '#app-host-container',
                hostClass: 'thy-layout',
                routerPathPrefix: '/app1',
                preload: true,
                entry: "/static/app2/index.html"
            },
            {
                name: 'app2',
                hostParent: '#app-host-container',
                hostClass: 'thy-layout',
                routerPathPrefix: '/app2',
                preload: true,
                entry: {
                  basePath: "/static/app1/"
                  manifest: "index.html"
                  scripts: [
                    'main.js'
                  ],
                  styles: [
                    'styles.css'
                  ]
                }
            }
        ]);

        // start monitor route changes
        // get apps to active by current path
        // load static resources which contains javascript and css
        // bootstrap angular sub app module and show it
        this.planet.start();
    }
}

3. Sub App define how to bootstrap

for NgModule application:

defineApplication('app1', {
    template: `<app1-root class="app1-root"></app1-root>`,
    bootstrap: (portalApp: PlanetPortalApplication) => {
        return platformBrowserDynamic([
            {
                provide: PlanetPortalApplication,
                useValue: portalApp
            },
            {
                provide: AppRootContext,
                useValue: portalApp.data.appRootContext
            }
        ])
            .bootstrapModule(AppModule)
            .then(appModule => {
                return appModule;
            })
            .catch(error => {
                console.error(error);
                return null;
            });
    }
});

for Standalone application: (>= 17.0.0)

defineApplication('standalone-app', {
    template: `<standalone-app-root></standalone-app-root>`,
    bootstrap: (portalApp: PlanetPortalApplication) => {
        return bootstrapApplication(AppRootComponent, {
            providers: [
                {
                    provide: PlanetPortalApplication,
                    useValue: portalApp
                },
                {
                    provide: AppRootContext,
                    useValue: portalApp.data.appRootContext
                }
            ]
        }).catch(error => {
            console.error(error);
            return null;
        });
    }
});

Documents

Sub app configurations

| Name | Type | Description | 中文描述 | | ------- | -------- | ----------| -------------- | | name | string | Application's name | 子应用的名字 | | routerPathPrefix | string | Application route path prefix | 子应用路由路径前缀，根据这个匹配应用 | | selector | string | selector of app root component | 子应用的启动组件选择器，因为子应用是主应用动态加载的，所以主应用需要先创建这个选择器节点，再启动 AppModule | | entry | string | PlanetApplicationEntry | entry for micro app, contains manifest, scripts, styles | 入口配置，如果是字符串表示应用入口 index.html，如果是对象, manifest 为入口 html 或者 json 文件地址，scripts 和 styles 为指定的资源列表，未指定使用 manifest 接口中返回的所有资源，basePath 为基本路由，所有的资源请求地址前会带上 basePath | | manifest | string | manifest json file path deprecated please use entry | manifest.json 文件路径地址，当设置了路径后会先加载这个文件，然后根据 scripts 和 styles 文件名去找到匹配的文件，因为生产环境的静态资文件是 hash 之后的命名，需要动态获取 | | scripts | string[] | javascript static resource paths deprecated please use entry.scripts | JS 静态资源文件访问地址 | | styles | string[] | style static resource paths deprecated please use entry.styles | 样式静态资源文件访问地址 | | resourcePathPrefix | string | path prefix of scripts and styles deprecated please use entry.basePath | 脚本和样式文件路径前缀，多个脚本可以避免重复写同样的前缀 | | hostParent | string or HTMLElement | parent element for render | 应用渲染的容器元素, 指定子应用显示在哪个元素内部 | | hostClass | string | added class for host which is selector | 宿主元素的 Class，也就是在子应用启动组件上追加的样式 | | switchMode | default or coexist | it will be destroyed when set to default, it only hide app when set to coexist | 切换子应用的模式，默认切换会销毁，设置 coexist 后只会隐藏 | | preload | boolean | start preload or not | 是否启用预加载，启动后刷新页面等当前页面的应用渲染完毕后预加载子应用 | | loadSerial | boolean | serial load scripts | 是否串行加载脚本静态资源 |

Communication between applications use GlobalEventDispatcher

import { GlobalEventDispatcher } from "@worktile/planet";

// app1 root module
export class AppModule {
    constructor(private globalEventDispatcher: GlobalEventDispatcher) {
        this.globalEventDispatcher.register('open-a-detail').subscribe(event => {
            // dialog.open(App1DetailComponent);
        });
    }
}

// in other apps
export class OneComponent {
    constructor(private globalEventDispatcher: GlobalEventDispatcher) {
    }

    openDetail() {
        this.globalEventDispatcher.dispatch('open-a-detail', payload);
    }
}

Cross application component rendering

import { PlanetComponentLoader } from "@worktile/planet";

// in app1
export class AppModule {
    constructor(private planetComponentLoader: PlanetComponentLoader) {
        this.planetComponentLoader.register([App1ProjectListComponent]);
    }
}

Load app1-project-list (selector) component of app1 in other app via PlanetComponentOutlet

<ng-container *planetComponentOutlet="'app1-project-list'; app: 'app1'; initialState: { search: 'xxx' }"></ng-container>

// or 
<ng-container planetComponentOutlet="app1-project-list"
              planetComponentOutletApp="app1"
              [planetComponentOutletInitialState]="{ term: 'xxx' }"
              (planetComponentLoaded)="planetComponentLoaded($event)">
</ng-container>

Load app1-project-list component of app1 in other app via PlanetComponentLoader, must be call dispose

@Component({
  ...
})
export class OneComponent {
    private componentRef: PlanetComponentRef;

    constructor(private planetComponentLoader: PlanetComponentLoader) {
    }

    openDetail() {
        this.planetComponentLoader.load('app1', 'app1-project-list', {
            container: this.containerElementRef,
            initialState: {}
        }).subscribe((componentRef) => { 
            this.componentRef = componentRef;
        });
    }

    ngOnDestroy() {
       this.componentRef?.dispose();
    }
}

FAQ

infinite loop load portal app's js

Because the portal app and sub app are packaged through webpack, there will be conflicts in module dependent files, we should set up additional config runtimeChunk through @angular-builders/custom-webpack, we expect webpack 5 to support micro frontend better.

// extra-webpack.config.js
{    
    optimization: {
        runtimeChunk: false
    }
};

throw error Cannot read property 'call' of undefined at __webpack_require__ (bootstrap:79)

Similar to the reasons above, we should set vendorChunk as false for build and serve in angular.json

 ...
 "build": {
    "builder": "@angular-builders/custom-webpack:browser",
    "options": {
          "customWebpackConfig": {
              "path": "./examples/app2/extra-webpack.config.js",
              "mergeStrategies": {
                "module.rules": "prepend"
              },
              "replaceDuplicatePlugins": true
          },
          ...
          "vendorChunk": false,
          ...
      },
  },
  "serve": {
      "builder": "@angular-builders/custom-webpack:dev-server",
      "options": {
          ...
          "vendorChunk": false
          ...
      }
  }
...

throw error An accessor cannot be declared in an ambient context.

this is TypeScript's issue, details see an-accessor-cannot-be-declared should setting skipLibCheck as true

"compilerOptions": {
    "skipLibCheck": true
}

Production env throw error Cannot read property 'call' of undefined use router lazy load

In webpack 4 multiple webpack runtimes could conflict on the same HTML page, because they use the same global variable for chunk loading. To fix that it was needed to provide a custom name to the output.jsonpFunction configuration, details see Automatic unique naming.

you should set a unique name for each sub application in extra-webpack.config.js

output: { jsonpFunction: "app1" }

Development

npm run start // open http://localhost:3000

or

npm run serve:portal // 3000
npm run serve:app1 // 3001
npm run serve:app2 // 3002

// test
npm run test

Roadmap

• [ ] Ivy render engine
• [ ] Supports Other frameworks as React and Vue

Contributors ✨

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!

LICENSE

MIT License