npm install --save-dev process-loader

module.exports = {
  module: {
    rules: [
      {
        test: /\.html$/,
        use: {
          loader: 'process-loader',
          options: {
            process: (content, path) => {
              // some pretty stuff
              console.log(path);
              console.log(content);
              return content;
            }
          }
        }
      }
    ]
  }
}