Requesting Pre Auth

Centrapay’s Pre Auth extension allows a patron to authorize payment up to a limit when the actual payment amount is not yet known.

Restrictions

Pre Auth payments are not supported in all cases.

1. Not all asset types support Pre Auth - Payment options for Asset Types that do not support Pre Auth will be excluded when a Payment Request is created with the preAuth flag.
2. Pre Auth is incompatible with Multi-Asset payments - Only one asset type can be authorized for a Pre Auth.

Pre Auth Flow

Pre Auth payments go through an orthogonal payment flow compared to Centrapay’s standard payment flow.

    sequenceDiagram
	autonumber

	participant Patron
	participant Integrator
	participant Centrapay

	note over Patron, Integrator: Connect with Patron
	Integrator->>Centrapay: Create Authorization

	note over Integrator: Poll for Payment Confirmation

	note over Integrator: ✅ Display Successful Authorization

	note over Integrator, Centrapay: ⏱️ Some time later..

	loop 0..Many (Up to Authorized Amount)
		Integrator->>Centrapay: Make Confirmations Against Authorized Funds
	end

	Integrator->>Centrapay: Release Remaining Authorized Funds
  

1. The Integrator places a hold on funds by creating an Authorization.
2. The Integrator draws down on authorized funds by making Confirmations against the authorization when the purchase is ready to be fulfilled.
3. The Integrator releases any remaining funds that have not been confirmed back to the Patron.

Authorize

An authorization is created when the Payment Request is created with the preAuth flag while Requesting Payment .

Once the authorization is successful, the Payment Request preAuthStatus is set to authorized.

Confirm

Merchants can draw down on authorized funds by making one or more confirmations against an authorized amount. Confirmations must be made with an idempotencyKey in order to prevent merchants from drawing down on authorized funds twice.

Confirmations against authorized funds have limits:

• Authorizations must be followed up with a confirmation - otherwise, the authorization will expire and the funds will be returned to the asset holder.

  The preAuthExpiry may be adjusted to match pre-determined expiry rules set by the asset provider.

• Multiple confirmations can be performed against an authorization but the total value cannot exceed the original authorized value.

Release

Authorized funds that have not been confirmed can optionally be released so that the asset holder is granted access to their remaining funds without needing to wait for the authorization to expire. Once releasing any remaining authorized funds is successful, the Payment Request preAuthStatus is set to released.

Refund

Refunds can be made against authorizations, confirmations, released authorizations and expired authorizations.

Refunds made against confirmations must include the confirmationIdempotencyKey field that is the same as the idempotencyKey used for original confirmation.

Void

Voiding a Payment Request will cancel a Payment Request and trigger any refunds necessary. This operation is useful if the Integrator needs to back out of a transaction due to a network error for example. Voiding can only be used up to 24 hours after the Payment Request was created.