We are implementing a third-party shipping (MachShip) API integration for our Zoho Commerce store and have made significant progress. However, we need guidance on a specific technical challenge.

Current Challenge:

We need to get the customer input to know the availability of forklift during checkout. Further, We need to capture live shipping rates during the checkout process (before order creation) and update the storefront with the calculated shipping cost.

We found the Zoho Commerce Storefront API endpoint that can update shipping:

PUT /storefront/api/v1/checkout/shipping-methods?checkout_id={checkout_id}

However, we're facing two critical blockers:

Checkout ID Access:

We cannot find how to capture the checkout_id during the active checkout session. It's not included in any webhook payload we've tested (now we have the salesorder module).

Webhook Trigger Point:

The Sales Order module webhook only fires after the order is placed, which is too late to update the storefront. We need a webhook or workflow trigger that fires during checkout (when the customer enters their shipping address. At the same time, we need to get an input (forklift availability) from the customer and send that information to the API.). And we have tried an embedded javascript to trigger the checkout process by adding <script></script> tags to header. but from that only we can extract the address and its not sufficient for get the quote.

Our Goal:

When a customer enters their shipping address, and enter the availability of forklift during checkout, we need to:

• Capture the checkout_id (since the salesfront API requires this ID.)

• Trigger our Zoho Flow webhook before creating the salesorder.

• Call MachShip API for live shipping quote

• Update the storefront with the calculated rate using the Storefront API.

We need to clarify,

• Is there a Checkout or Cart module available for webhooks/workflows?

• How can we access the checkout_id during an active checkout session?

• What is the recommended trigger point to call our webhook before order creation?

• Are there alternative approaches to achieve real-time shipping calculation in Zoho Commerce?