PlayFingerprintsPlugin.js

var crypto = require('crypto');
var fs = require('fs');

const PlayFingerprintsPlugin = function(options) {
  this.apply = this.apply.bind(this, options || {});
};
PlayFingerprintsPlugin.prototype.apply = (options, compiler) => {
  compiler.plugin('emit', (compilation, done) => {
    for (const filename in compilation.assets) {
      const hash = crypto.createHash("md5");
      hash.update(compilation.assets[filename].source());
      const md5 = hash.digest('hex');

      // Fingerprint .md5 file
      compilation.assets[`${filename}.md5`] = {
        source: () => md5,
        size: () => md5.length,
      };

      // Identical to original file but with hash prepended.
      compilation.assets[`${md5}-${filename}`] = compilation.assets[filename];
    };
    done();
  });
};