What is a Sale?

A sale is a transaction between two or more parties that involves the exchange of tangible or intangible goods, services, or other assets for money. In some cases, assets other than cash are paid to a seller.

In the case of the MPOS Companion API implementation the Sale transaction refers to the customer paying the goods or services received by means of tapping or inserting their bank card into the payment device.

The sale transaction is also used for purchase with cash (part of the sale is cash) and cashback (the entire sale amount is cash.)

The Sale request allows MPOS Applications to integrate card processing into their applications. To process a card payment the MPOS App must launch the Ecentric Payment App via an Android Intent call, to process the response intent data, in order to understand if the transaction succeeded of failed.

🚧
Note:
An auth token must exist before a payment can be requested.
Please refer to section Retail Auth Validation

How Does a Sale Work?

The diagram below displays an example of how a Sale works by making use of the Companion App (Here after known as the MPOS App), Payment App (Here after known as the Ecentric's Payment App), Transaction Processor (Here after known as the Ecentric Server) and Acquirer.

Sale transaction flow — Sale Transaction Flow

Process Description:

Step 1:

When a sale transaction is initiated on the MPOS App, the first step before processing the transaction, is to check if an authentication token is available in the request.

If there is an auth token available, then the transaction will continue as per normal.
If there is no auth token available, then the MPOS App will need to do a RETAIL_AUTH request in order to obtain a valid auth token, before a SALE transaction can be requested.

Step 2:

The MPOS App will initiate a SALE request, the SALE request will be sent to the Ecentric Payment App.

Step 3:

The Ecentric Payment App will process the card details and forward the SALE request to Ecentric's Server.

Step 4:

The Ecentric Server will validate the auth token in the request.

NOTE: If the auth token is not validated, the Ecentric Server will return an "invalid auth token" error to the Ecentric Payment App, and the transaction will be aborted.

Step 5:

The Ecentric Server will send a financial message to the Acquirer.

Step 6:

The Acquirer will the perform the necessary checks in order to validate and process the transaction.
Once the validation of the transaction has been performed, the Acquirer will respond with a financial message to the Ecentric Server, which contains the transaction outcome.

Step 7:

The Ecentric Server will return the transaction response to the Ecentric Payment App.

Step 8:

The Ecentric Payment App will then forward the transaction outcome to the MPOS App.

Step 9:

The MPOS App will be able to display the transaction outcome to the customer.

Sale Transaction Tutorial Video

Request

Sample Bundle: Sale

The following is an example of a SALE request for R10.00

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 1000

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 1000
"merchantName": "Payfacname"
"merchantCity": "Johannesburg"
"merchantRegionCode": "GP"
"merchantCountryCode": "ZA"
"merchantCategoryCode": "4891"
"additionalData": {
  "subMid": "574595612358745"
	"Street", "cnr Von Willich Ave &, Leonie St"
	"City", "Johannesburg"
	"Province", "GP"
	"Country_Code", "ZA"
	"Currency_Code", "710"
	"Postal_Code", "0157"
  }

Sample Bundle: Purchase with Cash

The following is an example of a Purchase request for R10.00 and a Cash amount of R50.00

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 6000 // The entire amount in cents
"cashAmount": 5000 // the cash amount in cents

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 6000 // The entire amount in cents
"cashAmount": 5000 // the cash amount in cents
"merchantName": "Payfacname"
"merchantCity": "Johannesburg"
"merchantRegionCode": "GP"
"merchantCountryCode": "ZA"
"merchantCategoryCode": "4891"
"additionalData": {
  "subMid": "574595612358745"
	"Street", "cnr Von Willich Ave &, Leonie St"
	"City", "Johannesburg"
	"Province", "GP"
	"Country_Code", "ZA"
	"Currency_Code", "710"
	"Postal_Code", "0157"
  }

Sample Bundle: Cashback

The following is an example of a Cashback request for R50.00

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 5000 // The entire amount in cents
"cashAmount": 5000 // The cash amount in cents

"launchType": "SALE"	
"merchantID": "770000000000123"
"authenticationKey": "e27b5ce6-8ba6-4746-9453-536728f7cbeb"
"transactionAmount": 5000 // The entire amount in cents
"cashAmount": 5000 // The cash amount in cents
"merchantName": "Payfacname"
"merchantCity": "Johannesburg"
"merchantRegionCode": "GP"
"merchantCountryCode": "ZA"
"merchantCategoryCode": "4891"
"additionalData": {
  "subMid": "574595612358745"
	"Street": "cnr Von Willich Ave &, Leonie St"
	"City": "Johannesburg"
	"Province": "GP"
	"Country_Code": "ZA"
	"Currency_Code": "710"
	"Postal_Code": "0157"
  }

Parameters

The following table describes the parameters of the SALE request message.

PARAMETERS	APPLIES TO	TYPE	DESCRIPTION	EXAMPLE
REQUIRED
launchType	All	STRING	Must be SALE Used for launching the Ecentric Payment App to process a payment.	SALE
merchantID	All	STRING	The merchant ID assigned to the merchant. The merchant ID will always be the same ID for a specific merchant. To be provided by Ecentric.	910100000000001
authenticationKey	All	STRING	The authentication token that was generated by the server on a successful retail auth call to the Ecentric Payment App.	e27b5456-8bff6-4746-94bg-367253356eb
transactionAmount	All	LONG	The full transaction amount to be charged in cents. This amount will include a cashAmount if it was specified.	1000
merchantName	PayFac	STRING	The store name of the sub-merchant. i.e. Payfacname * ".concat(shopName)) NB: The asterisk must appear in the 4th, 8th, or 13th character position, spaces are counted as characters.	4th position i.e. "Clash Melrose Arch" 8th position i.e. "Clash Melrose Arch" 13th position i.e. "Clash Melro*se Arch"
merchantCity	PayFac	STRING	The city where the sub-merchant's store is located.	Johannesburg
merchantRegionCode	PayFac	STRING	The region code where sub-merchant’s store is located. Must be the Alpha value for the region as seen in example column. EC – Eastern Cape FS – Free State GP – Gauteng KZN – KwaZulu-Natal LP – Limpopo MP – Mpumalanga NC – Northern Cape NW – North West WC – Western Cape	GP
merchantCountryCode	PayFac	STRING	The country code where sub-merchant's store is located.	ZA
merchantCategoryCode	PayFac	STRING	The category code of the sub-merchant's. 4-digit numeric code that identifies the type of business or service a sub-merchant provides. NB: It is essential that this field is populated accurately, as incorrect MCC assignment per merchant may result in penalties.	4891
OPTIONAL
merchantName	NON PayFac	STRING ALPHANUMERIC WITH SPACES	The name of the merchant that requested the transaction, as stored at the bank.	Merchant A
cashAmount	All	LONG	The amount of cash that was withdrawn in cents. The cashAmount will be included in the transacionAmount.	500
transactionDescription	All	STRING ALPHANUMERIC WITH SPACES	Reference description for the merchant’s records. If transactionDescription field is left blank in the request, Ecentric will automatically generate/populate the field with the RRN value for the transaction.	3rd party app desc
transactionReferenceNo	All	STRING ALPHANUMERIC	Reference number field that also appears in a merchant portal when available.	ref#123456
cellNumberToSMSReceipt	All	STRING NUMERIC	10-digit cell phone number for receipt SMS destination. Can be blank. NOTE: If isReceiptRequired is true then this is a mandatory field.	0721234567
emailAddressToSendReceipt	All	ALPHANUMERIC	Valid email address for receipt email destination. Can be blank. NOTE: If isReceiptRequired is true then this is a mandatory field.	[email protected]
isReceiptRequired	All	BOOLEAN	If set to true, at least one of the receipt parameters above needs to be set. If set to false the user will not be prompted to send a receipt after payment using the Ecentric Payment App. NOTE: According to VISA and Mastercard requirements, this must always be set to true unless the app developer is providing an alternative means to send a receipt	true
alwaysShowTransactionStatusScreen	All	BOOLEAN	Once the Ecentric Payment App has processed a transaction there is a status screen that shows the success/failure of processing. Set this flag to true if you would like this displayed otherwise false to hide it. Default is false.	true
externalSTAN	All	STRING NUMERIC	A systems trace number generated by some 3rd party ERP systems.	123456
externalRRN	All	STRING ALPHANUMERIC	A RRN generated by some 3rd party ERP systems. If externalRRN field is left blank in the request, Ecentric will automatically generate an externalRRN for the transaction.	ABCDEF123456
externalTransactionGUID	All	STRING ALPHANUMERIC	A GUID that identifies a specific transaction generated by 3rd party ERP systems.	2fdca02f-3cbe-4e8c-82ad-86a1a16b72e8
externalInvoiceGUID	All	STRING ALPHANUMERIC	A GUID that identifies a particular invoice that may appear on more than one transaction.	2fdca02f-3cbe-4e8c-82ad-86a1a16b72e9
transactionUuid	All	STRING ALPHANUMERIC	Unique ID of transaction. If transactionUuid field is left blank in the request, Ecentric will automatically generate a transactionUuid for the transaction.	bdf9d0af-17b3-48ca-8a0b-37dc52bf49bc
externalTransactionDateTime	All	STRING	A date and time the transaction was generated on the 3rd party ERP systems. Has the format of “yyyy-MM-dd'T'HH:mm:ss”	2017-04-28T09:30:00
externalTerminalId	All	STRING NUMERIC	A terminal identifier for device configured on the 3rd party ERP system. If externalTerminalId field is left blank in the request, Ecentric will automatically send the payment device TerminalId in the externalTerminalId field for the transaction.	98100010
latitude	All	STRING NUMERIC	A geolocation identifier indicating the latitude position of the device.	-28.1619942
longitude	All	STRING NUMERIC	A geolocation identifier indicating the longitude position of the device.	30.2350981
accuracy	All	STRING NUMERIC	A accuracy indicator of the geolocation.
additionalData	All	OBJECT	See Additional Parameters section for the AdditionalData Object.	N/A

Additional Parameters

📘
Note

The 'additionalData' object allows the MPOS App to pass data fields of any type to the server.

This 'additionalData' object is NOT interrogated or used by the Ecentric Payment App itself, but only passes the object through to the server.

AdditionalData Object

The following tables describes the additional parameters of the SALE request message.

PARAMETERS	APPLIES TO	TYPE	SIZE(MAX)	DESCRIPTION	EXAMPLE
REQUIRED
merchantInfo	PayFac	OBJECT	N/A	See parameters under MerchantInfo Object. example included in PayFac Sample Code SALE Request	N/A
subMid	PayFac	NUMERIC STRING	15	The unique ID for each sub merchant. Determined by the PayFac. example included in PayFac Sample Code SALE Request	574595612358745
Tokenization	All	OBJECT	N/A	See parameters under Tokenization Object. example included in All and PayFac Sample Code SALE Request	N/A
extendedTrxType	All	NUMERIC STRING	12	The unique 4 digit number configured on Postilion switch, which 3rd party integrators can use to route transactions to a different acquirer. Provided by Ecentric. example included in All and PayFac Sample Code SALE Request	1234

MerchantInfo Object

PARAMETERS	APPLIES TO	TYPE	SIZE(MAX)	DESCRIPTION	EXAMPLE
Street	PayFac	STRING ALPHANUMERIC WITH SPACES	255	The unique street address of the sub-merchant.	cnr Von Willich Ave &, Leonie St
City	PayFac	STRING ALPHANUMERIC	48	The city where the sub-merchant's store is located.	Johannesburg
Province	PayFac	STRING ALPHANUMERIC	2	The province where the sub-merchant's store is located. Must be the Alpha value for the province as seen in example column. EC – Eastern Cape FS – Free State GP – Gauteng KZN – KwaZulu-Natal LP – Limpopo MP – Mpumalanga NC – Northern Cape NW – North West WC – Western Cape	GP
Country_Code	PayFac	STRING NUMERIC	16	The country code where the sub-merchant's store is located.	ZA
Currency_Code	PayFac	STRING NUMERIC	3	The currency code that the sub-merchant uses to define the transaction currency. Currency code based on the ISO 8583 standard.	710
Postal_Code	PayFac	STRING NUMERIC	16	The postal code where the sub-merchant's store is located.	0157

Tokenization Object

PARAMETERS	APPLIES TO	TYPE	SIZE(MAX)	DESCRIPTION	EXAMPLE
MerchantUserID	All	NUMERIC STRING	16	Creates the ability to tokenize a customer card, in order for a PSP to perform subsequent transaction on the terminal as another means of securing customer information during transaction processing.	1

Sample Code

The following code needs to be implemented by the MPOS Application in order to invoke the Ecentric Payment App to initiate a SALE request message.

*See Sample Code SALE Response for the intentLauncher function

private void doSale() {
    Intent intent = new Intent();
   	intent.setClassName("com.ecentric.ecentricpay", "com.ecentric.ecentricpay.MainActivity");
    Bundle dataBundle = new Bundle();
    dataBundle.putString("launchType", "SALE");
  	dataBundle.putString("merchantID", "910100000000001")
    dataBundle.putString("authenticationKey", "received_authenticationKey");
    dataBundle.putLong("transactionAmount", 1000); // amount in cents
  
		JSONObject additionalData = new JSONObject();
		try {
      
      // Add extendedTrxType
			additionalData.put("extendedTrxType", "6705");
                                          
      // Create a Tokenization object
 			JSONObject tokenization = new JSONObject();
			tokenization.put("MerchantUserID", "1");
			additionalData.put("Tokenization", tokenization);
	 
			dataBundle.putString("additionalData", additionalData.toString());
		} catch (JSONException e) {
			e.printStackTrace();
		}

    intent.putExtra("ecentricBundle", dataBundle);
    try {
        intentLauncher.launch(intent);
    } catch (Exception e) {
        Log.e(TAG, "Error launching intent: " + e);
    }

private void doSale() {
    Intent intent = new Intent();
   	intent.setClassName("com.ecentric.ecentricpay", "com.ecentric.ecentricpay.MainActivity");
    Bundle dataBundle = new Bundle();
    dataBundle.putString("launchType", "SALE");
  	dataBundle.putString("merchantID", "910100000000001")
    dataBundle.putString("authenticationKey", "received_authenticationKey");
    dataBundle.putString("merchantName", "Cla*sh  Melrose Arch");
    dataBundle.putString("merchantCity", "Johannesburg");
    dataBundle.putString("merchantRegionCode", "GP"
    dataBundle.putString("merchantCountryCode", "ZA");
    dataBundle.putString("merchantCategoryCode", "4891");
    dataBundle.putLong("transactionAmount", 1000); // amount in cents
  
		JSONObject additionalData = new JSONObject();
		try {
      // Add subMid field
			additionalData.put("subMid", "574595612358745");
      
      // Add extendedTrxType
			additionalData.put("extendedTrxType", "6705");
      
      // Create a merchantInfo object
			JSONObject merchantInfo = new JSONObject();
			merchantInfo.put("Street", "cnr Von Willich Ave &, Leonie St);
			merchantInfo.put("City", "Johannesburg");
			merchantInfo.put("Province", "GP");
			merchantInfo.put("Country_Code", "ZA");
			merchantInfo.put("Currency_Code", "710");
			merchantInfo.put("Postal_Code", "0157");
			additionalData.put("Merchant_Info", merchantInfo);
                                          
      // Create a Tokenization object
 			JSONObject tokenization = new JSONObject();
			tokenization.put("MerchantUserID", "1");
			additionalData.put("Tokenization", tokenization);
	 
			dataBundle.putString("additionalData", additionalData.toString());
		} catch (JSONException e) {
			e.printStackTrace();
		}

    intent.putExtra("ecentricBundle", dataBundle);
    try {
        intentLauncher.launch(intent);
    } catch (Exception e) {
        Log.e(TAG, "Error launching intent: " + e);
    }

Response

📘
Note
Result of the transaction:

The resultCode will indicate the result of the sale request:
01 -> Successful
02 -> Declined
03 -> Aborted
04 -> Error

Sample Bundle

The following is an example of a SALE response bundle the MPOS Application will receive.

Receipt Bundle Section

    "adjustAmount": 10000,
    "appVersion": "2.2.0",
    "buildInfo": "com.ecentric.ecentricpay-DEBUG-Ecentric-[Ecentric_UAT]",
    "cashAmount": 0,
    "isReceiptDataAvailable": true,
    "launchType": "SALE",
    "merchantID": "910100000000001",
    "outstandingAmount": 0,
    "posId": "",
    "receiptBundle": { Please see receipt bundle section
    },
    "resultCode": "01",
    "resultDescription": "APPROVED",
    "serialNumber": "F31P606437P1024",
    "transactionAmount": 10000,
    "transactionLinkIdentifier": "1234567890123456789012",
    "transactionUuid": "d3d61b97-89b1-4543-8a43-b9c5db34af5f",
    "txType": "DEBIT"

Parameters

The following table describes the parameters of the SALE response message.

PARAMETERS	TYPE	DESCRIPTION	EXAMPLE
adjustAmount	LONG	Amount in cents to adjust the transactionAmount after the transaction, can be positive or negative. Tipping example: Tip of R20.00 → adjustAmount = 2000 Loyalty example: Redeems R50.00 with loyalty card → adjustAmount = -5000 Sale example: Sale success for R10.00 → adjustAmount = -1000 Sale declined → adjustAmount = 0	10000
appVersion	STRING	The software version currently running on the Ecentric Payment App.	2.0.0
buildInfo	STRING	Metadata that identifies the specific software build running on the payment device.	com.ecentric.ecentricpay-DEBUG-Ecentric-[Ecentric_UAT]
cashAmount	LONG	Approved cashAmount.	500
isReceiptDataAvailable	STRING	Boolean indicating whether a receiptBundle object is available. Will always be included for approved or declined transactions.	true
launchType	STRING	Echo of the launchType used to launch the Ecentric Payment App.	SALE
merchantID	STRING	Echo of the merchantID used in the request.	910100000000001
outstandingAmount	LONG	transactionAmount + adjustAmount Tipping example: Tip of R1.50 to R10.00: transactionAmount = 1000 adjustAmount = 150 outstandingAmount = 1150 Sale example: Sale success of R10.00 transactionAmount = 1000 adjustAmount = -1000 outstandingAmount = 0	0
posId	STRING	N/A for Companion API Integrations
receiptBundle	STRING	Consists of a sub-bundle of server parameters that can be used by the partner application to create a receipt.	See Receipt Bundle Section
resultCode	STRING	Represents the final outcome of the transaction. ● 01: SUCCESSFUL ● 02: DECLINED ● 03: ABORTED ● 04: ERROR	01
resultDescription	STRING	A user readable representation of the above resultCode i.e. Approved for resultCode 01. If the bank or switch approves or declines the transaction, the response description is included in this field.	APPROVED
serialNumber	STRING	The serial number for the device that was used for the RETAIL_AUTH intent call.	PC05P2CG10036
transactionAmount	LONG	Approved total transactionAmount.	1000
transactionLinkIdentifier	STRING	Mastercard Only The transactionLinkIdentifier is returned in the response message. The POS is responsible for storing this value if unmatched refunds need to be processed. Please see Refund Transaction for more information.	1234567890123456789012
transactionUuid	STRING	Echo of the Unique ID of a transaction.	bdf9d0af-17b3-48ca-8a0b-37dc52bf49bc
txType	STRING	Transaction type	DEBIT

Sample Code

The following code needs to be implemented by the MPOS Application to decode the SALE transaction outcome and resume the MPOS App flow accordingly.

When the response is returned the calling app needs to override the onActivityResult() method and can be done as follows:

private final ActivityResultLauncher<Intent> intentLauncher = registerForActivityResult(
       new ActivityResultContracts.StartActivityForResult(),
       result -> {
           if (result.getResultCode() == Activity.RESULT_OK) {
               Intent data = result.getData();
               if (data != null) {
                   Bundle responseBundle = new Bundle(data.getBundleExtra("ecentricApplicationResponse"));
                   String launchType = responseBundle.getString("launchType");
                   String resultCode = responseBundle.getString("resultCode");
                 		// Determine if the transaction was successfully executed using returned resultCode
                   Boolean success = false;
                   if (resultCode != null && (resultCode.matches("00") || resultCode.matches("01"))) {
                       success = true;
                   }

                   if (responseBundle.get("errorBundle") != null) {
                       Bundle errorBundle = new Bundle(responseBundle.getBundle("errorBundle"));
                   }
               }
           } else {
               Log.e(TAG, "Received error resultCode: " + result.getResultCode());
           }
       }
);

Error Handling

The following table contains typical errors that might occur and how to handle these errors:

ERROR MESSAGE	SOLUTION
Incorrect merchantID	Ensure that you have entered the correct merchantID.
authenticationKey is invalid	When your authenticationKey is invalid, you will receive an error message indicating that the authenticationKey is invalid, a RETAIL_AUTH request needs to be done to obtain a valid authenticationKey.
transactionAmount not present	Ensure that you are sending through a valid transactionAmount.
Duplicate UUID	Ensure that a unique UUID is sent through for every new sale transaction.

Sample Bundle

The following is an example of a SALE ERROR response bundle that the MPOS Application will receive.

"resultDescription": "ABORTED",
"errorBundle": {
    "description": "ERROR",
    "reference": "",
    "errorType": "TRANSACTION",
    "message": "Transaction cancelled by user"
  },
 "buildInfo": "Ecentric_DEBUG_Ecentric_INT",
 "isReceiptDataAvailable": false,
 "resultCode": "03",
 "merchantID": "910100000000001",
 "serialNumber": "PC05P2CG10036",
 "launchType": "SALE",
 "cashAmount": 0,
 "appVersion": "1.9.8",
 "transactionAmount": 1000