Class CheckoutClient

Cancel an in-flight checkout session (e.g. the buyer abandoned the embed). Idempotent — cancelling an already-cancelled session is a no-op; a completed session cannot be cancelled (the API returns 422 already_completed).

Returns either a completion or {status: 'requires_action'} when the card needs a 3-D Secure challenge — narrow with isRequiresAction() before reading orderId.

Read a checkout session's current state — status tells you whether the buyer is still in it (open, processing) or it has settled (completed, cancelled, expired). Use it to decide whether a session can be resumed or cancelled instead of tracking that yourself.