Checkout validation

[tlb_mk]

I would like to implement a checkout validation to prevent users to complete purchase when any products in their cart matche a certain case in checkout page.

I attempted to do this by using shopify function (https://shopify.dev/docs/apps/checkout/validation/create-simple-validation-rules), but I realized that the validation is also executed when users add a item into the cart.

I know this sounds good in most cases, but not for my store theme, because the cart.liquid is fully customized using js.  It does not seem to be feasible to display returned error message in proper section of my cart.liquid.

So, I would like to know if it is possible to run the validation only in checkout page, but not in cart modal.

I am still learning about all the checkout extensibility stuff.

I hope I get some answer for this.

Thanks.

[Philip_Crumpton · Accepted solution]

I found this answer on another thread after having the same issue.

https://community.shopify.com/c/shopify-apps/how-can-i-use-cart-and-checkout-validation-function-to-...

There is a buyerJourneyStep that you can use to see if they're on "CHECKOUT_INTERACTION"

[tlb_mk]

Hi, Philip.

Thanks!! It solves my problem!!

[Philip_Crumpton]

Glad I could help! I just now discovered you should also check for "CHECKOUT_COMPLETION" for compatibility with one-page checkout. CHECKOUT_INTERACTION apparently doesn't trigger on one-page checkout when clicking Pay Now.

[matt_hunter]

Thanks for this followup Philip, you saved me a lot of time and pain!