Callback support via Webhook

This optional feature allows for the creation of a webhook, which will trigger Smobilpay to send a HTTP POST payload to the webhook's configured URL when a payment status has been changed.
This feature is only enabled on demand. If desired please provide to mavaince ops team:

URL: A webhook URL that is accessible from the public web (or whitelist the Smobilpay IP addresses)
Secret: to be used during signature generation (optional)
Skip SSL Verification: to be set to true if the callback shall be sent to a target that does not have a valid certificate (we do not recommend enabling this, but will be so to allow, e.g. self signed certificates)

Delivery headers

HTTP POST payloads that are delivered to your webhook's configured URL endpoint will contain several special headers:

Header	Description
X-Delivery	A unique id to identify the delivery to prevent duplicate processing – each unique callback has its own id.
X-Ptn	Payment notification Number (PTN – received from the API after successful payment). This refers to the payment which the status has been changed
X-Signature	The HMAC hex digest of the response body. This header will be sent if the webhook is configured with a secret. The HMAC hex digest is generated using the sha1 hash function and the secret as the HMAC key. Varification is optional. However, integrators are advised to validate (recreate the signature and compare) the signature to confirm that the callback has indeed been sent by Smobilpay. Tool to generate an hmac from the example online: https://www.freeformatter.com/hmac-generator.html The X-Signature will be set to an empty string (““) if no secret was configured.

Delivery Content

Header	Description
timestamp	Timestamp when payment entered final state
trid	Transaction Identifier generated in external system. Will be set to an empty string (““) if no transaction identifier was provided.
errorCode	Error code pointing to error if encountered during payment processing - Error Codes & Server Responses
status	SUCCESS or ERROR

Example callback request for a payment which changed to status SUCCESS

JSON

POST /exampleEndpoint HTTP/1.1

X-Delivery: 72d3162e-cc78-11e3-81ab-4c9367dc0958
X-Ptn: 99999152778369900057856272351928
X-Signature: 13c3bda9ff43530abc8ae63755d9bb101e554c94
Content-Type: application/json
Content-Length: 70

{
  "timestamp":"2018-05-31 16:21:40",
  "trid":"13550",
  "errorCode": "0",
  "status":"SUCCESS"
}

Signature generation

Body to sign	JSON `{"timestamp":"2018-05-31 16:21:40","trid":"13550","status":"SUCCESS"}`
Secret Key used during signing	“secret”
Calculated Signature (SHA-1)	13c3bda9ff43530abc8ae63755d9bb101e554c94