google-tag-manager.html

<!--
@license
Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
Code distributed by Google as part of the polymer project is also
subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
-->

<link rel="import" href="../polymer/polymer.html">

<!--
A Polymer 1.2 wrapper element for google tag manager.

Example:

    <google-tag-manager cid="GTM-XXXXXX"></google-tag-manager>

@demo demo/index.html
@hero hero.svg
-->

<dom-module id="google-tag-manager">
  <template>
    <noscript>
      <iframe src={{_computeSrc(cid)}} height="0" width="0" style="display:none;visibility:hidden"></iframe>
    </noscript>
  </template>

  <script>
    Polymer({
      is: 'google-tag-manager',

      properties: {
        /**
         * `cid` is the container ID
         */
        cid: {
          type: String,
        }
      },

      // Element Lifecycle

      attached: function() {
        (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
        new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
        j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
        '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
        })(window,document,'script','dataLayer',this.cid);
      },


      // Element Behavior

      _computeSrc: function(cid) {
        return '//www.googletagmanager.com/ns.html?id=' + cid;
      }
    });
  </script>
</dom-module>