Federated State Management

Federated State Management Overview

At its core, federated state management 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 federated state management pays off across the whole codebase: fewer surprises, easier testing, and smoother onboarding. The snippet below is a solid starting point.

const { ModuleFederationPlugin } = require('webpack').container;

module.exports = {
  plugins: [
    new ModuleFederationPlugin({
      name: 'shell',
      remotes: { catalog: 'catalog@http://localhost:3001/remoteEntry.js' },
      exposes: {},
      shared: { react: { singleton: true }, 'react-dom': { singleton: true } },
    }),
  ],
};

ModuleFederationPlugin configures which modules an app exposes, consumes, and shares.

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

Module Federation Cheatsheet

Key Module Federation settings related to federated state management.

How Federated State Management Works in Module Federation

Federated State Management 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.

ModuleFederationPlugin configures which modules an app exposes, consumes, and shares.

• 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 Federated State Management

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

Key Takeaways

• Federated State Management is a core part of working effectively with Module Federation.
• Start small and keep federated state management focused on a single responsibility.
• Apply consistent patterns so federated state management scales across your project.
• Test and document federated state management to keep it maintainable over time.