AttributionApp Cross-domain Tracking Snippet

attribution-crossdomain-tracking.js

// Attribution snippet code
window.Attribution=window.Attribution||[];window.Attribution.methods=["trackSubmit","trackClick","trackLink","trackForm","pageview","identify","group","track","ready","alias","page","once","off","on"];window.Attribution.factory=function(e){return function(){var t=Array.prototype.slice.call(arguments);t.unshift(e);window.Attribution.push(t);return window.Attribution}};for(var i=0;i<window.Attribution.methods.length;i++){var key=window.Attribution.methods[i];window.Attribution[key]=window.Attribution.factory(key)}window.Attribution.load=function(e){if(document.getElementById("attribution-js"))return;var t=document.createElement("script");t.type="text/javascript";t.id="attribution-js";t.async=true;t.src="//scripts.attributionapp.com/attribution.js";var n=document.getElementsByTagName("script")[0];n.parentNode.insertBefore(t,n)};window.Attribution.load();

// set your project key
window.Attribution.projectId="YOUR_APP_KEY";

// cross-domain hook
Attribution.ready(function() {
  // list of your hostnames that you want to share visitors
  var crossDomains = ['hostA.com', 'www.exampleB.net', 'otherC.com'];

  // search current url for anonymous_id
  var currentUrl = new URL(window.location.href);
  var anonymousId = currentUrl.searchParams.get('anonymous_id');

  if (anonymousId) {
    // set anonymous id
    Attribution.user().anonymousId(anonymousId);
  } else {
    // read generated anonymous id
    anonymousId = Attribution.user().anonymousId();
  }

  // track current pageview
  Attribution.page();

  // check every link and tag external links to our crossDomains with anonymous_id
  var elements = document.body.getElementsByTagName('a');
  for (var i = 0; i < elements.length; i++) {
    var link = elements[i].getAttribute('href');

    // we use try here because not every link is a valid url
    try {
      var url = new URL(link);

      // if not current hostname and hostname is in our cross-domain list
      if ((url.hostname != currentUrl.hostname) && (crossDomains.indexOf(url.hostname) > -1)) {
        var newLink = link + ((link.indexOf('?') > -1) ? '&' : '?') + 'anonymous_id=' + anonymousId;
        // update link to include anonymous_id
        elements[i].setAttribute('href', newLink);
        // console.warn(link + ' matched, updated to ' + newLink)
      } else {
        // console.warn(link + ' domain is not in our list')
      }
    }
    catch (e) {
      // console.warn(link + ' is not an URL');
    }
  }
});