dgenezini/blazor.modulefederation.angular

Angular Module Federation wrapper for Blazor

Generates an Angular application exposing the registered Blazor components through module federation.

The exposed components accept input parameters and subscription to events.

Disclaimer: This package is not ready for production.

Current issues and limitations

• Only works with Blazor WebAssembly;
• Blazor App server needs to have CORS enabled.

Blazor Configuration

The source code for the Angular application is generated by an MSBuild task. For this, we need to configure which component will be exposed.

Counter.razor:

In the .razor file of the component include the attribute GenerateModuleFederationComponent at the top.

@attribute [GenerateModuleFederationComponent]
@using Blazor.ModuleFederation.Angular;

...

Program.cs:

In the Program.cs file, register the component with the RegisterForModuleFederation method.

var builder = WebAssemblyHostBuilder.CreateDefault(args);

builder.RootComponents.RegisterForModuleFederation<Counter>();

...

Project.csproj:

In the .csproj file, configure the following parameters:

• ModuleFederationName: Name of the module that will be exposed;
• MicroFrontendBaseUrl: The URL where the Blazor application will be published to;
• BuildModuleFederationScript: Enable or disable the Angular module federation wrapper generation;
• IsProduction: If the Angular app will be compiled with production configuration;

<PropertyGroup>
    <ModuleFederationName>blazormodule</ModuleFederationName>
</PropertyGroup>

<PropertyGroup Condition="'$(Configuration)' == 'DEBUG'">
    <MicroFrontendBaseUrl>http://localhost:5289/</MicroFrontendBaseUrl>
    <BuildModuleFederationScript>False</BuildModuleFederationScript>
    <IsProduction>False</IsProduction>
</PropertyGroup>

<PropertyGroup Condition="'$(Configuration)' == 'RELEASE'">
    <MicroFrontendBaseUrl>http://localhost:8080/</MicroFrontendBaseUrl>
    <BuildModuleFederationScript>True</BuildModuleFederationScript>
    <IsProduction>True</IsProduction>
</PropertyGroup>

Host Configuration

ComponentLoader:

Create a loader component to load the remote Blazor component. Don't forget to include it in the app module.

import {
  Component,
  OnInit,
  ViewContainerRef,
  ComponentRef,
  EventEmitter
} from '@angular/core';

import { loadRemoteModule } from '@angular-architects/module-federation';

@Component({
  selector: 'counter-loader',
  template: ''
})
export class CounterLoaderComponent implements OnInit {
  constructor(
    private vcref: ViewContainerRef
  ) {}

  async ngOnInit() {
    const { CounterComponent } = await loadRemoteModule({
      remoteEntry: 'http://localhost:8080/js/remoteEntry.js',
      remoteName: 'blazormodule',
      exposedModule: './Counter',
    });

    const componentRef: ComponentRef<{
        startFromId: number;
        onDataLoaded: EventEmitter<any>;
      }> = this.vcref.createComponent(CounterComponent);

    componentRef.instance.startAt = 100;
    componentRef.instance.onDataLoaded.subscribe(evt => console.log('Data Loaded'));
  }
}

AppComponent:

Include the loader component in the HTML.

<div class="toolbar" role="banner">
  <span class="header-title">Host App</span>
</div>

<div class="content" role="main">
  <counter-loader></counter-loader>
</div>

webpack.config.js

Import the Blazor exposed component in the ModuleFederationPlugin.remotes.

const ModuleFederationPlugin = require("webpack/lib/container/ModuleFederationPlugin");
const mf = require("@angular-architects/module-federation/webpack");
const path = require("path");
const share = mf.share;

const sharedMappings = new mf.SharedMappings();
sharedMappings.register(
  path.join(__dirname, 'tsconfig.json'),
  [/* mapped paths to share */]);

module.exports = {
  output: {
    uniqueName: "hostApp",
    publicPath: "auto"
  },
  optimization: {
    runtimeChunk: false
  },
  resolve: {
    alias: {
      ...sharedMappings.getAliases(),
    }
  },
  experiments: {
    outputModule: true
  },
  plugins: [
    new ModuleFederationPlugin({
        library: { type: "module" },

        remotes: {
            blazormodule: 'blazormodule@http://localhost:8080/js/remoteEntry.js'
        },

        shared: share({
          "@angular/core": { singleton: true, strictVersion: true, requiredVersion: 'auto' },
          "@angular/common": { singleton: true, strictVersion: true, requiredVersion: 'auto' },
          "@angular/common/http": { singleton: true, strictVersion: true, requiredVersion: 'auto' },
          "@angular/router": { singleton: true, strictVersion: true, requiredVersion: 'auto' },

          ...sharedMappings.getDescriptors()
        })

    }),
    sharedMappings.getPlugin()
  ],
};

Sample applications

https://github.com/dgenezini/BlazorModuleFederationSample