Utility Purchases

How Interwallet Transfer works (step by step flow)

SOURCE APP SIDE: The source app is purchasing utility (Airtime)

  1. Initiate a Utility Purchase

Communication is sent to the merchants endpoint(Outgoing transaction webhook)

Below is a screen showing where the Finswich merchant sets their transaction or settlement webhook for a registered app

PAYLOAD sent to merchant's end to initiate purchase of utility

{
	"event": "TRANSACTION_INITIATE",
	"data": {
		"user_reference": "poormeggriffin",
		"amount": "200.0",
		"currency": "ngn",
		"txn_reference": "UTL-hZ4KKPAvGR43kYLL1687247368",
		"transfer_type": "UTILITY",
		"recipient": {
			"product_id": "4611",
			"product_type": "Mobile Pin / Voucher",
			"product_category": "Mobile PIN",
			"operator": "Nigeria Airtel",
			"value_recipient": "+2347081332677"
		},
		"mode": "TEST"
	}
}
KeyTypeDescription

Event

String

the name of the even being broadcasted to the merchant. Initiate informs the merchant

Data

Object

The object containg the info of the utility purchase

user_reference

String

the identifier for the user making the purchase

amount

Number

the amount to be debited from the user

currency

String

the currency code of the buyer

txn_reference

String

The identifier for the transaction

transfer_type

String

The type of transaction. On finswich transactions can be of diffrent types. e.g. interwallet, bank transfers, utility e.t.c.

Recipient

Object

The object containing

product_id

String

the identifier for the utility product.

product_type

String

The type of utility being purchased

product_category

String

the category of the utility being purchased eg Mobile Pin

operator

String

the service provider

value_recipient

String

the phone number where the data or airtime would be loaded on.

mode

String

The transaction can either be in the test mode or live mode. In test actual money is not transferred.

200 RESPONSE

{
"status":"success",
"data": {
"user_category":str (optional)
}
}

If the response returned is not in the 200 range or response.status != “success”, the transaction process is terminated immediately and that transaction reference becomes invalid.

If user_category is returned then we automatically run an internal policy check using the category sent. If the policy check fails, we call their policy notification API or Email and notify the merchant and then the transaction process is terminated.

Its advisable to store this transaction (txn_reference) as it will be used to complete the remaining steps

  1. Trigger OTP

Payload sent to merchant to trigger the sending of OTP to their end user endpoint = source app outgoing transaction webhook

{
	"event": "SEND_OTP",
	"data": {
		"user_reference": "poormeggriffin",
		"txn_reference": "UTL-hZ4KKPAvGR43kYLL1687247368",
		"debit_platform": "Kuda",
		"credit_platform": "Utility",
		"amount": "200.0",
		"currency": "ngn",
		"recipient_user": "None",
		"mode": "TEST"
	}
}

200 response structure

{
"status":"success"
}

If the response returned is not 200 or the response.status != “success”, we do not terminate the txn. If the call to this endpoint is successful, we respond back to the client informing them that an OTP has been sent to their phone number This is the same endpoint and payload called when the user clicks the OTP resend button This transaction ref is valid for only 60minutes.

  1. Complete Utility Purchase (for merchant to verify OTP received by their user and start the real process of purchasing the utility )

Payload sent to source app to complete transfer endpoint = Merchant's outgoing settlement webhook

{
	"event": "COMPLETE_TRANSACTION",
	"data": {
		"otp": "23341",
		"txn_reference": "UTL-hZ4KKPAvGR43kYLL1687247368",
		"user_reference": "poormeggriffin",
		"mode": "TEST"
	}
}

Here the merchant verifies the OTP. If verification is succesful merchant proceeds to truly complete the transaction by communicating with the Finswich Transfer endpoint.

200 response structure

{
"status":"success"
}

If the response is 200 Ok, this means the txn was successful

3b. Calling the Finswich Transfer API

On the originator app’s end, when they receive this request, they would call Finswich’s transfer API to actually make the transfer. This is what the endpoint and the payload looks like:

endpoint (prod) = https://finswich-api.fuspay.finance/api/v1/app-transfer/wallet endpoint (sandbox/test) = https://finswichstaging.instance.exchange/api/v1/app-transfer/wallet method = POST

Sample Request

headers = {
"Accept": "application/json",
"x-finswich-signature": hashed_payload,
"x-public-key": public_key,
"x-origin": your whitelisted URL 
}


payload = {"auth_code": otp, "txn_reference": txn_reference}

//the OTP code is not for verification but logging on Finswich end

Sample Response

200 OK

response = {
"status":"success",
"data":{},
"message":"Transaction completed successfully"
}

400 response structure

response = {
"status":"error",
"data":{},
"message":"Transaction failed"
}

If a 200 response is returned and response.status == “success” this means the source app’s wallet been debited.

3c. Giving value to the user

In certain utility events like the purchase of power there is need to provide some sort of token to, as the token is what is used by the user to get the utility purchased.

So there is a need to broadcast another event to the Finswich Merchant. This event enables merchant to efficiently dispatch mails and notifications to their end users.

{
	"event": "UTILITY_TRANSACTION_VALUE_READY",
	"data": {
		"txn_reference": "UTL-hZ4KKPAvGR43kYLL1687247368",
		"user_reference": "poormeggriffin",
		"utility_details": {
			"operator": "Nigeria Airtel",
			"product_id": "4611",
			"product_type": "Mobile Pin / Voucher",
			"value_recipient": "+2347081332677",
			"product_category": "Mobile PIN"
		},
		"utility_value": {
			"pin": { "number": "1234567890", "serial": "ZZZ123456", "instructions": "This is a test pin" },
			"instructions": "None"
		},
		"mode": "TEST"
	}
}

3d. Failure at the Utility Providers end. Merchant and end user refund

For cases where the transaction fails at the utility providers end we also broadcast an event to the Finswich Merchant. This event signifies to the merchant that their Finswich wallet has been credited back with what was charged for their user's utility purchase and therefore the merchant can also refund their end user.

 {"event": "UTILITY_TRANSACTION_REVERSAL",
            "data": {
                "txn_reference": UTL-p3kIL9sKruTBv3kL1686731317,
                "user_reference": poormeggriffin,
                "amount": 3000,
                "currency": NGN,
                "utility_details": {
	                                "operator": "Nigeria Airtel",
	                                "product_id": "4611",
	                                "product_type": "Mobile Pin / Voucher",
	                                "value_recipient": "+2347081332677",
	                                "product_category": "Mobile PIN"
			            }
                    }
}

MINUTES_MAP = {1: 5, 2: 60, 3: 1440, 4: 4320} 
//The first retry is 5 mins after the first attempt to credit. The second retry is 60 mins after the first retry...the 3rd retry is 1440 mins after the second retry and so on.

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