Awesome

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.

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✨ 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

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