getUserIP (Promise)

getUserIP.js

/**
 * Get the user IP throught the webkitRTCPeerConnection
 *
 * @return {Promise<string>}
 *
 * @see Get the client IP address with Javascript on Safari {@link https://stackoverflow.com/questions/46925857/get-the-client-ip-address-with-javascript-on-safari}
 */
function getUserIP() {
  //compatibility for firefox and chrome
  var myPeerConnection =
    window.RTCPeerConnection ||
    window.mozRTCPeerConnection ||
    window.webkitRTCPeerConnection;
  var pc = new myPeerConnection({ iceServers: [] });
  var noop = function() {};
  var localIPs = {};
  var ipRegex = /([0-9]{1,3}(\.[0-9]{1,3}){3}|[a-f0-9]{1,4}(:[a-f0-9]{1,4}){7})/g;
  var key;

  var resolve;
  var reject;
  var promise = new Promise(function (res, rej) {
    resolve = res;
    reject = rej;
  });

  function iterateIP(ip) {
    if (!localIPs[ip]) resolve(ip);
    localIPs[ip] = true;
  }

  //create a bogus data channel
  pc.createDataChannel('');

  // create offer and set local description
  pc.createOffer()
    .then(function(sdp) {
      sdp.sdp.split('\n').forEach(function(line) {
        if (line.indexOf('candidate') < 0) return;
        line.match(ipRegex).forEach(iterateIP);
      });
      pc.setLocalDescription(sdp, noop, noop);
    })
    .catch(reject);

  //listen for candidate events
  pc.onicecandidate = function(ice) {
    if (
      !ice ||
      !ice.candidate ||
      !ice.candidate.candidate ||
      !ice.candidate.candidate.match(ipRegex)
    ) {
      return;
    }
    ice.candidate.candidate.match(ipRegex).forEach(iterateIP);
  };

  return promise;
}

// Usage
getUserIP().then(ip => console.log(ip));

Not working in Chrome 77