Using Unity Xross ID for customer sharing across multiple stores, can it work with the Storefront API?

Shopify Discussion
1

We are considering sharing customers across multiple stores managed with Shopify Plus using Unity Xross ID.
We understand that when a customer registered in the main store A logs in to the secondary store B with the same ID and password, the customer is created in the secondary store B. However, we would like to confirm whether this same operation will occur when executing the customerAccessTokenCreate in the Storefront API during login.
Specifically, is it possible to operate such that the main store A uses a web browser, while the secondary store B uses an external e-commerce application through the Storefront API?

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Hi @store_K

No, customerAccessTokenCreate will not work for this. That mutation is store-specific and will fail with an “Unidentified customer” error because the customer does not exist in Store B’s database.

The automatic customer creation you see in the web browser is handled by Multipass (Shopify’s SSO), which is a separate, web-based redirect flow.

To make your external app work, it must also use the Multipass flow for the initial login. Your app needs to authenticate the user against your main system, get a Multipass token, and then load a web view to Store B’s Multipass URL. This action will create the customer account in Store B, allowing you to use customerAccessTokenCreate for all future logins.

Hope this helps!

4

Hi @PieLab

Thank you for providing a detailed explanation.

I would like to confirm one point regarding the sharing of customer information across multiple stores.
From my understanding, both the “Multipass API” and “Unity Xross ID” can be utilized.

However, if we use either the Multipass API or Unity Xross ID (e.g., via ChannelUnity), does this mean that Multipass (Shopify’s SSO) is applied in both cases?