plugin.js

plugin.js

const minify = require('html-minifier').minify;
const fs = require('fs');

class HtmlMinifierPlugin {
  constructor(options) {
      this.options = options;
  }
  apply(compiler) {
    compiler.plugin("emit", (compilation, callback) => {
        fs.readFile(this.options.template, 'utf-8', (err, html) => {
            if (err) {
                callback();
                throw Error();
            }

            const minified = minify(html, {
                collapseWhitespace: true
            });

            compilation.assets[this.options.filename] = {
                source: function() {
                  return minified;
                },
                size: function() {
                  return minified.length;
                }
            }
            callback();
        });
    });
  }
}

module.exports = HtmlMinifierPlugin;