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This guide explains the Pre-Authorization vending flow. This process is key to minimizing risk because it approves payment before the customer selects a product.

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Payment Flow

Visualize the Pre-Authorization process with the diagram below, which illustrates each step of the single vending session flow, from product selection to payment authorization and dispensing.
Below is a breakdown of the diagram:
  1. The consumer presents the card to the Nayax Device.
  2. The Nayax Device sends an authorization request to the Nayax Server.
  3. The Nayax Server forwards the authorization request to the Billing Provider.
  4. The Billing Provider sends an authorization response (approved) to the Nayax Server.
  5. Nayax Server sends the authorization response (approved) back to the Nayax Device.
  6. The peripheral’s SDK begins the session and triggers the “session begin” event:
vmc_vend_event_handler_cb(vm_vend_event_on_session_begin)
  1. Message to the consumer: “Please Select a Product.”
  2. The consumer selects a product.
  3. The peripheral’s SDK sends a “vend request” to the Nayax Device:
  4. The peripheral’s SDK handles transaction data received from the Nayax Device via Transfer Data command (said data includes information about the Nayax transaction ID and the consumer’s card details):
vmc_vend_event_handler_cb(vm_vend_event_on_transaction_info)
  1. The peripheral’s SDK triggers the “vend approved” event:
vmc_vend_event_handler_cb(vm_vend_event_on_vend_approved)
  1. The peripheral dispenses the product/ provides the service to the consumer
  2. The SDK reports vend success:
vmc_vend_vend_status(&session, __true)
And completes the vend session: 
vmc_vend_vend_session_complete_lowlevel()
  1. Message to the consumer: “Please Take Product.”
  2. Nayax Device sends a settlement request to the Nayax Server.
  3. Nayax Server forwards the settlement request to the Billing Provider.
  4. The billing Provider sends a settlement response (OK) to the Nayax Server.
  5. Nayax Server sends the settlement response (OK) back to the Nayax Device.
  6. The vending session ends.
  7. Message to Card Holder: “Thank you & Goodbye.”

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See Also

Payment Flows

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Methods & Functions