What is the data layer?

Google Tag Manager (GTM) Relies on a global array (window.dataLayer) to push event objects to and process them from. GTM listens to this array for events and reacts to each event. For example, after an add to cart event on a website a snapshot of the data layer may look as follows...

window.dataLayer = [
	{ event: "gtm.dom", ... }, // user loads a page
	{ event: "dl_view_item",  ... }, // user views a product
	{ event: "dl_add_to_cart",  ... }, //	user adds a product
  ...
];

// Pushing a new event into the data layer
window.dataLayer.push({ event: "dl_remove_from_cart", ... });

Special Properties and Utilities

Route Changes

Data Layer Events

Some of these events are automatically pushed to the data layer by GTM. What you’ll need to implement and push into the data layer at the correct times are the following events:

Base Event

• User Data dl_user_data: The base event that should be fired before any other event, and on all virtual page changes.

Account Management Events

• Signup dl_sign_up: When a user signup occurs. If account management is handled on Shopify’s online store and not on the headless site, then this event can be disregarded.
• Login dl_login: When a user logs in. If account management is handled on Shopify’s online store and not on the headless site, then this event can be disregarded.

Ecommerce Funnel Events

• View Item List dl_view_item_list: Collection/Product Listing pageview.
• View Search Results dl_view_search_results: Search results pageview.
• Item Click dl_select_item: Item clicked from collection or search page.
• Product Detail View dl_view_item: Item view.
• Product Add to Cart dl_add_to_cart: Add to cart.