How to avoid duplicate dependencies in Gutenberg blocks

Question

The WordPress Gutenberg block build script uses wordpress/dependency-extraction-webpack-plugin to build the blocks without WordPress dependencies being repeated but what about other dependencies?

If I build a plugin with 10 blocks and they all re-use dependencies, the WordPress build script will embed the dependency in every block bundle.

Is there a good way to handle this without having to re-create webpack build by myself?

Answer 1

WordPress Dependency extraction plugin @wordpress/dependency-extraction-webpack-plugin basically makes your ES6 dependency imports use WordPress scripts instead of adding them to the bundle over and over.

This makes modules registered and enqueued in WordPress (including but not limited to jquery, moment and react and wp.* modules) to be properly excluded from builds.

You can add additional dependencies to be excluded (make sure you register/enqueue in WordPress) with requestToHandle callback.

For example for excluding say react-sortable component from build registered as react-sortable script in WordPress (PHP),

module.exports = {
  plugins: [
    new DependencyExtractionWebpackPlugin( {
      requestToHandle: function ( module ) {
        if ( module === 'react-sortable' ) {
          return 'react-sortable'; // WordPress script handle
        }
      }
    } ),
  ]
}