bundle-html-scripts.js

// Extracts all script src's from an html file
// then minifies, and concatenates them into one file.
// Author: leathan
// License: MIT
process.argv[2] && ExtractBundle(process.argv[2], process.argv[3] || null, process.argv[4] || null);
module.exports = ExtractBundle;
function ExtractBundle(file, skip, verbose) {
  !file && !console.log("Provide a link.") && process.exit(1);
  const { minify } = require("uglify-es");
  const request = require('request');
  const fs = require('fs');
  host = /(.*)\//.exec(file)[1];

  const minified = [], results = [];
  var found = 0;

  // If their is no new data found in 15 seconds, atleast one server hung
  // so check if lastfound(15 seconds ago) === found(nowish) exit.
  (function forever(lastfound) {
    setTimeout(()=>{ if(found === lastfound) !console.log("Atleast 1 server hung.") && process.exit(1); else forever(found) }, 15000)
  })();
  const obj = {};
  request(file, (_, __, data) => {
    !data && !console.log("No data from link.") && process.exit(1);
    const sources = data.replace(/<!--[\s\S]*?-->/mg,'') // Remove comments
    .match(/<script[\s\S]*?src[\s\S]*?>[\s\S]*?<\/script>/mg) // Match all script tags
    .map(_=>_.match(/src\s*=\s*"(.*)"/)[1]); // Return array of source locations.
    for(let i = 0, l = sources.length; i < l; i++) {
      source = sources[i];
      if((skip||[]).includes(source.slice(1))) { results[i] = ""; continue }
      const url = /\/\//.test(source) ? source : host + source;
      verbose && !console.log("fetching " + url);
      request(url, (err, res, body) => {
        results[i] = minify(body).code || {error: true};
        minified[i] = minify(body, {mangle:false}).code
        if(results[i].error) !console.log("Error parsing " + url) && process.exit(1);
        if(++found === sources.length) {
          fs.writeFileSync('bundle.min.js', minified.join(""));
          fs.writeFileSync('bundle.mangled.js', results.join(""));
          console.log('Saved output to ./bundle.min.js and ./bundle.mangled.js');
          process.exit(0);
        }
      })
    }
 })
}