I need to read cookie that are set by Google Tag Manager.

Right now if Google Tag Manager is loaded first time for end-user I can't read cookies (because it happens later, but not immediately).

Is there a good way (callback?) that can help me to read cookies once they are set? This issue is only relevant if user visits page first time.

I need to read cookie that are set by Google Tag Manager.

Right now if Google Tag Manager is loaded first time for end-user I can't read cookies (because it happens later, but not immediately).

Is there a good way (callback?) that can help me to read cookies once they are set? This issue is only relevant if user visits page first time.

• javascript
• google-analytics
• google-tag-manager

• you can use the pageload event like in this question stackoverflow./questions/16552560/… – ozkanpakdil Commented Apr 15, 2015 at 11:01
• Are the cookies you want to read set from withing a Trigger in Google Analytics and/or from a third-party script? – Philippe Sawicki Commented Apr 17, 2015 at 23:53
• @PhilippeSawicki they are from Google Analytics – Dmytro Pastovenskyi Commented Apr 19, 2015 at 9:09
• If I understand correctly, you would like to read the __utm* or _ga cookies? – Philippe Sawicki Commented Apr 20, 2015 at 13:16
• @PhilippeSawicki _ga – Dmytro Pastovenskyi Commented Apr 21, 2015 at 13:41

1 Answer 1

From the discussion in the ments below the question, I would suggest the following solution (assuming you also send Pageviews to Google Analytics). Examples are based on Simo Ahava's (excellent) blog.

(Please note that I haven't had the opportunity to test it thoroughly, as I am currently unable to create a plete test case for this setup -- there might be some hiccups)

1. Create a Variable to read the _ga cookie

Reference: https://www.simoahava./analytics/macro-magic-google-tag-manager/#1-client-time

This will return the value for the cookie with name specified (be careful in where you use the value read, as there is always a chance that cookies are rejected by the User's browser policies).

Create a new Variable, with:

• Variable Name of GA Cookie
• Cookie Name of _ga

_{(source: simoahava.)}

2. Define a callBackFunction

Reference: https://www.simoahava./analytics/macro-magic-google-tag-manager/#8-hitcallback-with-a-universal-analytics-tag & https://www.simoahava./analytics/macro-magic-google-tag-manager/#6-get-clientid-using-_ga-cookie

This callback function will be executed right after the Pageview is sent (i.e. after the _ga cookie is set).

Create a Custom JavaScript Macro with the following code:

function () {
   return function () {
      // Code to be executed in order to read the cookie:
      try {
         var gaCookie = {{GA Cookie}};

         // Do what you need to with the cookie here:
         // ...

         return gaCookie;
      } catch (e) {
         console.log('No Universal Analytics cookie found.');
         return 'N/A';
      }
   }
}

3. Define a hitCallback after sending the Pageview

Reference: https://www.simoahava./analytics/macro-magic-google-tag-manager/#8-hitcallback-with-a-universal-analytics-tag

This will execute the callback function you just defined right after the Pageview is sent.

In the Fields to set option of your Pageview Tag, set:

• Field Name to hitCallback
• Value to {{callBackFunction}}

Hope it can help you move forward.