3. Implement Callback URL

When a full payment is made a JSON request is sent to the merchant’s paymentWebhookURL.

We do a POST request when sending the payment details to the merchant's callback URL.

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When is a Webhook sent to Merchant?
Webhook is only sent when the customer has made full payment for the request raised

Webhook Request

Parameter Name	Type	Description
checkoutRequestID	`integer`	Unique transaction ID identifying the transaction as provided by the checkout platform.
merchantRequestID	`string`	Unique transaction ID identifying the transaction as given by the merchant.
requestStatusCode	`integer`	Request status after the customer makes the payment. 178 - indicating the request was fully paid for 179 - indicating the request was partially paid for but expired 129 - Request expired without payments 102 - Insufficient funds 101 - Invalid pin/canceled 99 - Generic Failed Payment Status
requestStatusDescription	`string`	Request status description.
MSISDN	`string`	Customer mobile number.
serviceCode	`string`	Identifier for the service that request has be raised to.
accountNumber	`string`	Reference for the item being paid for eg: Pay TV account number or Airline ticket number.
currencyCode	`string`	The three character currency code (ISO 4217) used for the payment.
amountPaid	`double`	Amount received from customer.
requestCurrencyCode	`string`	A three character currency code (ISO 4217) that the transaction was converted to for collection.
requestAmount	`integer`	Amount of the transaction request after conversion.
requestDate	`string`	Date and time payment was logged into the Cellulant Payment Gateway.
payments	`JSON Array`	List of individual payments made for the checkout request.
serviceChargeAmount	`integer`	Extra charge set if available for the service.
originalRequestAmount	`double`	The original amount that was passed on the request to checkout.
originalRequestCurrencyCode	`string`	Original currency code provided on the request to checkout
amountPaidInOriginalCurrency	`double`	Total amount paid in Original Currency. (Sum of amountPaidInOriginalCurrency in payments array)
conversionRate	`double`	Conversion rate used to convert from original currency to payment currency
failedPayments	`JSON Array`	An array of failed payment attempts by the customer. Available only if service is enabled to receive failed notifications. Contact Cellulant to activate this option.

Payments array for both failed and successful payments array.

Parameter Name	Type	Description
payerClientCode	`string`	A unique identifying code of the payment option that will be used to initiate the request or was used to complete the payment. E.g. 'MPESA' for Mpesa payment option.
payerClientName	`string`	Identifier of the option that was used to make the payment e.g. Mpesa.
payerTransactionID	`string`	A unique identifier of the payment as logged on the payment channel's platform. This may be logged by the merchant for easier transaction tracking and support for customers.
currencyCode	`string`	The three character currency code (ISO 4217) used for the payment.
amountPaid	`string`	The amount received from the payment channel the customer paid from.
amountPaidInOriginalCurrency	`double`	Amount received from the customer in the original currency
originalRequestCurrencyCode	`string`	Original currency code provided on the request to checkout
customerName	`string`	The name of the customer who made the payment. Available for payment options where the customer names are provided.
hubOverallStatus	`string`	Internal Cellulant processing status for the payment.
MSISDN	`string`	The mobile number that the payment originated from.
serviceCode	`string`	Identifier for the service that request has be raised to.
cpgTransactionID	`string`	A unique identifier to identify the payment on the Cellulant's payment Gateway.
accountNumber	`string`	Reference for the item being paid for eg: Pay TV account number or Airline ticket number.
datePaymentReceived	`string`	The date in which the payment was logged onto the cellulant payment gateway.
payerNarration	`string`	This is the MNO or bank payment narration shared to Cellulant.

{
    "serviceCode": "TESTSERVICE",
    "MSISDN": "254713123888",
    "originalRequestCurrencyCode": "KES",
    "originalRequestAmount": 200,
    "checkoutRequestID": 4826296,
    "requestCurrencyCode": "KES",
    "requestAmount": "200.00",
    "accountNumber": "3201HR00",
    "requestStatusCode": 178,
    "requestStatusDescription": "Request fully paid",
    "merchantTransactionID": "r77az121236884",
    "requestDate": "2018-08-28 12:12:38.0",
    "currencyCode": "KES",
    "amountPaid": 200,
    "amountPaidInOriginalCurrency": 200,
    "conversionRate":1.0,
    "serviceChargeAmount": 0,
    "payments": [
        {
            "MSISDN": 254713123888,
            "payerClientName": "Safaricom Kenya Limited",
            "currencyCode": "KES",
            "amountPaid": 200,
            "amountPaidInOriginalCurrency": 200,
            "originalRequestCurrencyCode": "KES",
            "cpgTransactionID": "288852770",
            "serviceCode": "TESTSERVICE",
            "payerTransactionID": "OHS01A3K",
            "hubOverallStatus": 139,
            "accountNumber": "3201HR00",
            "customerName": "Customer",
            "payerClientCode": "SAFKE",
            "datePaymentReceived": "2018-08-28 12:13:33.0",
            "payerNarration": "successful"
        }
    ],
    "failedPayments": [
        {
           "MSISDN": 254713123888,
            "payerClientName": "Safaricom Kenya Limited",
            "currencyCode": "KES",
            "amountPaid": 0,
            "cpgTransactionID": "288852770",
            "serviceCode": "TESTSERVICE",
            "payerTransactionID": "OHS01A3K",
            "hubOverallStatus": 138,
            "accountNumber": "3201HR00",
            "customerName": "Customer",
            "payerClientCode": "SAFKE",
            "datePaymentReceived": "2018-08-28 12:13:33.0",
            "payerNarration": "failed"
        }
    ]
}

{
    "serviceCode": "TESTSERVICE",
    "MSISDN": "254713123888",
    "originalRequestCurrencyCode": "KES",
    "originalRequestAmount": 200,
    "checkoutRequestID": 4826296,
    "requestCurrencyCode": "KES",
    "requestAmount": "200.00",
    "accountNumber": "3201HR00",
    "requestStatusCode": 178,
    "requestStatusDescription": "Request fully paid",
    "merchantTransactionID": "r77az121236884",
    "requestDate": "2018-08-28 12:12:38.0",
    "currencyCode": "KES",
    "amountPaid": 200,
    "amountPaidInOriginalCurrency": 200,
    "conversionRate":1.0,
    "serviceChargeAmount": 0,
    "payments": [],
    "failedPayments": [
        {
           "MSISDN": 254713123888,
            "payerClientName": "Safaricom Kenya Limited",
            "currencyCode": "KES",
            "amountPaid": 0,
            "cpgTransactionID": "288852770",
            "serviceCode": "TESTSERVICE",
            "payerTransactionID": "OHS01A3K",
            "hubOverallStatus": 138,
            "accountNumber": "3201HR00",
						"paymentStatus":"INVALID_PIN",
            "customerName": "Customer",
            "payerClientCode": "SAFKE",
            "datePaymentReceived": "2018-08-28 12:13:33.0",
            "payerNarration": "failed"
        }
    ]
}

Failed Payment Status (Work in Progress)

Kindly note on callback under the failed payments array we will send the field paymentStatus with the exact status code of why the request failed on the MNO's end. Here overallStatus for the request will be 99 or 101 or 102 however the individual failed payment will have the correct status code with the reason for failure. Note the new field showing the actual failure reason will be under failedPayments[].paymentStatus

Status Code	Description
FAILED	Generic failure reason given by the payment provider.
TIMEOUT	There was a timeout when MNO was sending request to end users handset or customer did not enter their pin in time.
INVALID_PIN	Customer entered incorrect pin.
BLOCKED	Customers mobile number was blocked by the MNO.
INSUFFICIENT_BALANCE	This indicates customer does not have enough money in their wallet to complete these transactions.
CANCELLED	Request was cancelled by the customer.
LIMIT_EXCEEDED	Declined due to limit rule: would exceed or fall below the transfer limits
SUCCESS	Payment was debited successfully.
ERROR	Internal error / network timeout when trying to reach the MNO / Authentication error when sending the request to the MNO
NOT_ALLOWED	Customer is not allowed to make such a transaction either due to decimals or their account is on hold or it is a suspected fraudulent transaction
ENGAGED	Handset has a similar request they are processing hence cannot proceed.
INVALID	For the request sent one of the parameters are not correct and has a problem.
ACCOUNT_NOT_FOUND	MSISDN or wallet is not available on the acquirers end.

Expected Web-hook Response

The merchant is expected to send back a response with the following parameters:

Parameter Name	Type	Description	Required
checkoutRequestID	`integer`	Unique transaction ID identifying the transaction as provided by the checkout platform.	TRUE
merchantTransactionID	`string`	Unique transaction ID identifying the transaction as given by the merchant.	FALSE
statusCode	`integer`	A status indicating the result of payment processing. 180 - The payment was rejected by the merchant. Only accepted if the notification was for a full request. 183 - The payment was accepted by the merchant. Only accepted if the notification was for a full request. 188 - The payment/request was received. Acknowledgement will be initiated later if the notification was for a fully paid request. See Acknowledge Payment on custom API for details. For a failed payment notification, no further action will be taken. 189 - There was an error in processing the payments/request on the merchant's platform. The request should be re-sent for processing.	TRUE
statusDescription	`string`	A description of the status provided above	TRUE
receiptNumber	`string`	A transaction ID indicating the receipt of the payments.	TRUE

Examples

Payment processed successfully

{
  "checkoutRequestID": 4826296,
  "merchantTransactionID": "abcd-efg-hijklm",
  "statusCode": "183",
  "statusDescription": "Payment processed successfully",
  "receiptNumber": "r77az121236884"
}

Payment processing failed

{
  "checkoutRequestID": 4826296,
  "merchantTransactionID": "abcd-efg-hijklm",
  "statusCode": "180",
  "statusDescription": "Payment was not processed successfully",
  "receiptNumber": ""
}