JSzip test

jszip-test.js

// Run in console on loremflicker.com

class ScriptLoader {
  constructor(scriptUrl) {
    this.script = document.createElement('script');
    this.script.src = scriptUrl;
//     this.head = document.querySelector('head');
    this.firstScriptTag = document.getElementsByTagName('script')[0];
  }

  load() {
    return new Promise((resolve, reject) => {
      this.script.async = true;
      this.script.onload = () => resolve();
      this.script.onerror = () => reject();
  //       this.head.appendChild(this.script);
      this.firstScriptTag.parentNode.insertBefore(this.script, this.firstScriptTag);
    });
  }
}

new ScriptLoader("https://cdnjs.cloudflare.com/ajax/libs/jszip-utils/0.0.2/jszip-utils.min.js").load().then(() => {
  new ScriptLoader("https://cdnjs.cloudflare.com/ajax/libs/jszip/3.1.5/jszip.min.js").load().then(() => {
    new ScriptLoader("https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/1.3.8/FileSaver.min.js").load().then(() => {
      let zip = new JSZip();
      zip.file("Hello.txt", "Hello World\n");
      var img = zip.folder("images");
      img.file('test.jpg', urlToPromise('https://loremflickr.com/g/320/240/paris'), {base64: true});
      zip.generateAsync({type:"blob"})
      .then(function(content) {
         // see FileSaver.js
         saveAs(content, "example.zip");
       });
    })
    .catch((e) => {
      console.log(e);
    })
  })
})

function urlToPromise(url) {
  return new Promise((resolve, reject) => {
    JSZipUtils.getBinaryContent(url, function (err, data) {
      if(err) {
        reject(err);
      } else {
        resolve(data);
      }
    });
  });
}