Dynamic Remote URLs

Dynamic Remote URLs Overview

At its core, dynamic remote urls is about doing one thing well inside your Module Federation project. Once you understand the pattern, you can apply it consistently across features and teams.

Good dynamic remote urls pays off across the whole codebase: fewer surprises, easier testing, and smoother onboarding. The snippet below is a solid starting point.

// remote (webpack.config.js)
const { ModuleFederationPlugin } = require('webpack').container;

module.exports = {
  plugins: [
    new ModuleFederationPlugin({
      name: 'catalog',
      filename: 'remoteEntry.js',
      exposes: {
        './ProductList': './src/ProductList',
      },
      shared: ['react', 'react-dom'],
    }),
  ],
};

A remote exposes modules through remoteEntry.js so hosts can load them at runtime.

Dynamic Remote URLs Example

new ModuleFederationPlugin({
  name: 'app',
  filename: 'remoteEntry.js',
  exposes: { './Widget': './src/Widget' },
  remotes: { other: 'other@http://host/remoteEntry.js' },
  shared: { react: { singleton: true } },
});

• Start from a minimal Dynamic Remote URLs example and grow it only as needed.
• Keep configuration explicit so Dynamic Remote URLs behaves the same in every environment.
• Name things clearly so teammates understand your Dynamic Remote URLs at a glance.
• Add tests around Dynamic Remote URLs early to lock in expected behaviour.

Module Federation Cheatsheet

Key Module Federation settings related to dynamic remote urls.

How Dynamic Remote URLs Works in Module Federation

Dynamic Remote URLs builds on Module Federation's ability to load code from another independently built and deployed application at runtime. Each app can be a host, a remote, or both.

A remote exposes modules through remoteEntry.js so hosts can load them at runtime.

• Remotes expose modules through a remoteEntry.js manifest.
• Hosts declare remotes and import exposed modules dynamically.
• Shared dependencies are deduplicated, ideally as singletons.
• Each micro frontend builds and deploys on its own schedule.

Practical Guidance for Dynamic Remote URLs

In production, dynamic remote urls needs careful version management and graceful failure handling. Align shared dependency versions and always render a fallback when a remote cannot load.

Common Mistakes

• Copying dynamic remote urls snippets without understanding what each line does.
• Skipping error handling and edge cases when wiring up dynamic remote urls.
• Leaving dynamic remote urls untested, so regressions slip into production.
• Over-engineering dynamic remote urls before you actually need the extra flexibility.

Key Takeaways

• Dynamic Remote URLs is a core part of working effectively with Module Federation.
• Start small and keep dynamic remote urls focused on a single responsibility.
• Apply consistent patterns so dynamic remote urls scales across your project.
• Test and document dynamic remote urls to keep it maintainable over time.