google-analyticsgoogle-tag-managergoogle-datalayercustom-dimensions

GTM how to set custom dimension to GA page view?

I found this question mentioned that the custom dimension value must set before ga('send', 'pageview');

But what if I use Google Tag Manager?

dataLayer.push({
    'postId': '{{ $post->id }}',
    'userId': '{{ auth()->user()->id }}',
});

I've set up the data layer variable to GTM to trigger GA. But when I look at the GA report, and filter by custom dimension, it's not working.

I checked with the debug, Tags Fired On This Event shows below

GTM chrome plugin

How do I set the custom dimension before it sent to GA pageview?

Solution

  • You would need to define the datalayer BEFORE loading of the GTM script.

    Example to place at the top of the page before GTM is loaded:

    <script>
  dataLayer = [{
   'postId': '{{ $post->id }}',
   'userId': '{{ auth()->user()->id }}',
  }];
</script>

    When you do this, the data is available right away.

    Another thing you can do is instead of using the datalayer, if the pages are rendered server-side, is to use tags with the postid and userid as values. This will ensure they're loaded before GTM.

    https://developers.google.com/tag-manager/devguide#adding-data-layer-variables-to-a-page