Integrity Digest

The Integrity Digest works in conjunction with Prepared Payments, Idempotency Tokens, and Webhooks to provide a secure and predictable transaction flow for online payments.

When creating a payment request using either Prepared Payments or directly with Transact the merchant may include an IntegritySecret. In subsequent responses and webhooks this secret will be used to create a cryptographic hash of key response fields named IntegrityDigest.

tip

If you use a static secret you should rotate it regularly, or you can use a unique secret per call.

warning

IntegritySecret must only be sent over direct channels, Prepared Payments or Payments API. Never include the IntegritySecret on public web pages as this will compromise the security of the resulting IntegrityDigest.

Request Fields

Field Name	Description	Req'd	Size	Type
IntegritySecret	Provides a secret only known to the merchant	O	50 max.	A

Response Fields

Field Name	Description	Size	Type
IntegrityDigest	Contains a hash of key response fields to confirm the authenticity of the raw data	20 max.	A

Validating the Integrity Digest

TransactDirect provides a simple enpoint to validate the IntegrityDigest.

https://elite.monek.com/secure/IntegrityCheck.ashx

Field Name	Description	Source	Req'd	Size	Type
IntegritySecret	The secret used to create the transaction	Req	M	50 max.	A
IdempotencyToken	The idempotency token from the request	Req	O	50 max.	A
PaymentReference	The merchants payment reference	Req	O	50 max.	A
Amount	The transaction amount	Req/Res	M	10 max.	A
CurrencyCode	The transaction currency code	Req/Res	M	3	A
IntegrityDigest	The digest received in the transaction response	Res	M	50 max.	A
RequestTime	The request time as confirm in the transaction response	Res	M	25 max.	ISO 8601
CrossReference	The transaction Cross Reference	Res	M	50 max.	A
ResponseCode	The 2 digit transaction response code	Res	M	1	A
ResponseMessage	The response message text	Res	M	80 max.	A

If the Integrity hash is correct then IntegrityCheck.ashx will return a 200 OK response code.

In all other scenarios, including missing or bad data, the response code will be 400 BAD REQUEST