What is Module Federation and How Can It Be Accomplished in Next.js?

Introduction

With the recent advancements in web development, it has become essential for developers to find new ways to share code between different applications. Module Federation is a technique that enables developers to share code between multiple applications. In this blog post, we will discuss what Module Federation is and how it can be accomplished in Next.js.

What is Module Federation?

Module Federation is a technique that allows developers to share code between multiple applications. It enables developers to break down an application into smaller, more manageable parts, which can be shared between different applications. This technique is useful in microservice architectures, where multiple applications need to interact with each other.

With Module Federation, developers can share code without having to create a separate library or package. This technique enables developers to build applications that are more modular, scalable, and easier to maintain.

How Can Module Federation Be Accomplished in Next.js?

Next.js is a popular React framework that enables developers to build server-side rendered applications. With Next.js, developers can easily implement Module Federation and share code between different applications.

To accomplish Module Federation in Next.js, developers need to use the @module-federation/client and @module-federation/server packages. These packages enable developers to create a shared module that can be used across different applications.

To implement Module Federation in Next.js, developers need to do the following:

1. Create a shared module that can be used across different applications.
2. Configure the @module-federation/server package to expose the shared module.
3. Configure the @module-federation/client package to consume the shared module.

By following these steps, developers can easily implement Module Federation in Next.js and share code between different applications.

Sample Code

Here's an example of how to implement Module Federation in Next.js:

// app.js
import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';

ReactDOM.render(<App />, document.getElementById('root'));

// shared.js
import React from 'react';

const SharedComponent = () => {
  return <h1>Shared Component</h1>;
};

export default SharedComponent;

// next.config.js
module.exports = {
  webpack: (config, options) => {
    config.plugins.push(
      new options.webpack.container.ModuleFederationPlugin({
        name: 'app',
        filename: 'static/runtime/remoteEntry.js',
        remotes: {},
        exposes: {
          './SharedComponent': './shared',
        },
        shared: {
          react: {
            eager: true,
            singleton: true,
            requiredVersion: false,
          },
        },
      })
    );

    return config;
  },
};

// App.js
import React from 'react';
import dynamic from 'next/dynamic';

const SharedComponent = dynamic(() => import('app/SharedComponent'));

const App = () => {
  return (
    <div>
      <h1>App</h1>
      <SharedComponent />
    </div>
  );
};

export default App;

Another example on Dev.to

What if there are 1000 components that need exposed

If there are 1000 components that need to be exposed, developers can use a wildcard to expose all components in a directory. For example, if all components are stored in the components directory, developers can use the following syntax:

exposes: {
  './components': true,
},

This will expose all components in the components directory. Developers can also use a regular expression to filter the components that should be exposed. For example, to expose all components that start with Button, developers can use the following syntax:

exposes: {
  './components/Button.*': true,
},

This will expose all components that start with Button.

What if there are 1000 components that need exposed

If there are 1000 components that need to be consumed, developers can use a wildcard to consume all components in a directory. For example, if all components are stored in the components directory, developers can use the following syntax:

remotes: {
  app: '<http://localhost:3000/remoteEntry.js>',
},
shared: {
  react: {
    eager: true,
    singleton: true,
    requiredVersion: false,
  },
},
exposes: {},
remotes: {
  app: '<http://localhost:3000/remoteEntry.js>',
},
shared: {
  react: {
    eager: true,
    singleton: true,
    requiredVersion: false,
  },
},
consumes: {
  './components': true,
},

This will consume all components in the components directory. Developers can also use a regular expression to filter the components that should be consumed. For example, to consume all components that start with Button, developers can use the following syntax:

remotes: {
  app: '<http://localhost:3000/remoteEntry.js>',
},
shared: {
  react: {
    eager: true,
    singleton: true,
    requiredVersion: false,
  },
},
exposes: {},
remotes: {
  app: '<http://localhost:3000/remoteEntry.js>',
},
shared: {
  react: {
    eager: true,
    singleton: true,
    requiredVersion: false,
  },
},
consumes: {
  './components/Button.*': true,
},

This will consume all components that start with Button.