github-sso-auth-code-flow #6

openWindow.js

// From https://gist.github.com/gauravtiwari/2ae9f44aee281c759fe5a66d5c2721a2
// By https://gist.github.com/gauravtiwari

/* global window */

const loginTab = (myUrl) => {
  const windowArea = {
    width: Math.floor(window.outerWidth * 0.8),
    height: Math.floor(window.outerHeight * 0.5),
  };

  if (windowArea.width < 1000) { windowArea.width = 1000; }
  if (windowArea.height < 630) { windowArea.height = 630; }
  windowArea.left = Math.floor(window.screenX + ((window.outerWidth - windowArea.width) / 2));
  windowArea.top = Math.floor(window.screenY + ((window.outerHeight - windowArea.height) / 8));

  const sep = (myUrl.indexOf('?') !== -1) ? '&' : '?';
  const url = `${myUrl}${sep}`;
  const windowOpts = `toolbar=0,scrollbars=1,status=1,resizable=1,location=1,menuBar=0,
    width=${windowArea.width},height=${windowArea.height},
    left=${windowArea.left},top=${windowArea.top}`;

  const authWindow = window.open(url, '_blank', windowOpts);
  // Create IE + others compatible event handler
  const eventMethod = window.addEventListener ? 'addEventListener' : 'attachEvent';
  const eventer = window[eventMethod];
  const messageEvent = eventMethod === 'attachEvent' ? 'onmessage' : 'message';

  // Listen to message from child window
  const authPromise = new Promise((resolve, reject) => {
    eventer(messageEvent, (msg) => {
      if (!~msg.origin.indexOf(`${window.location.protocol}//${window.location.host}`)) {
        authWindow.close();
        reject('Not allowed');
      }

      if (msg.data.payload) {
        try {
          resolve(JSON.parse(msg.data.payload));
        }
        catch(e) {
          resolve(msg.data.payload);
        }
        finally {
          authWindow.close();
        }
      } else {
        authWindow.close();
        reject('Unauthorised');
      }
    }, false);
  });

  return authPromise;
};

export default loginTab;