Read a cart line's `viewKey` from the `CartLine` type

The CartLine type now exposes a viewKey field, so you can correlate a returned cart line with the viewKey you sent to cartLinesUpdate and cartLinesRemove.

What's new

• CartLine.viewKey returns the same viewKey your Liquid storefront renders, alongside the existing UUID id.

How to use

Previously, identifying a line by viewKey was input-only: you could send a viewKey, but the response returned a UUID id with no viewKey to map back. You can now read it directly off the line.

query CartLines($cartId: ID!) {
  cart(id: $cartId) {
    lines(first: 10) {
      edges {
        node {
          id
          viewKey
        }
      }
    }
  }
}

The field reads a value the cart already stores, so existing UUID-based correlation keeps working unchanged.