The EM.context data structure contains all the relevant data within the iFrame where the externalized module is implemented. It allows for the creation of custom dataLayer objects needed by certain TMSs such as Tealium and Adobe. Learn how to use EM.context to Create Custom dataLayer Objects.

Discover the power of EM.context, a data structure that holds essential information within the iFrame housing your externalized module, enabling you to craft bespoke dataLayer objects crucial for Tag Management Systems like Tealium and Adobe. Dive into our guide to master the art of utilizing EM.context for creating custom dataLayer objects tailored to your needs.

All the available parameters of the EM dataLayer can be found in the following link:

How to find the EM.context

To find the EM.context in the iFrame, navigate to the URL where the externalized module is positioned and open the ‘Console’ within Google Developer Tools.

In the ‘Console,’ access the iFrame using the ‘JavaScript context’:

Once you have accessed the iFrame, type ‘EM.context’:

Creating a new dataLayer object using the EM.context

For this example, we will use the EM.context to populate Tealium’s utag_data object.

1. Firstly, identify the parameters needed in the script

The parameters that require dynamic values will use JavaScript. For example:

You can access the variables in the EM.context using JavaScript paths:

2. Use JavaScript to map the parameters from the EM.context

3. Insert the JavaScript paths to the TMS dataLayer object

Include the JavaScript paths for the corresponding variables:

You can apply the same principles to any type of data structure. Once you complete this step, your custom dataLayer is ready for publication!

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