Flutter plugin compatible version of goSellSDK library for both Android and iOS that fully covers payment/authorization/card saving/card tokenization process inside your Android application. Original SDKS

Getting Started

Table of Contents

  1. Requirements
  2. Installation
    1. Installation with pubspec.yaml
  3. Usage
    1. Configure Your App
    2. Configure SDK Session
    3. Transaction Modes
    4. Customer
    5. Configure Payment Type
    6. Use Tap Pay Button
    7. Handle SDK Result
    8. Apple Pay Setup


To use the SDK the following requirements must be met:

  1. Visual Studio - InteliJ Idea
  2. Dart 2.7.1 or newer
  3. Flutter: >=3.0.0 or newer
  4. iOS 11 or later
  5. XCode 12 or later


Include goSellSDK plugin as a dependency in your pubspec.yaml

     go_sell_sdk_flutter: ^2.2.9

Configure your app

goSellSDK should be set up. To set it up, add the following lines of code somewhere in your project and make sure they will be called before any usage of goSellSDK.

 * Configure App. (You must get those keys from tap)
  bundleId: Platform.isAndroid? "ANDROID-PACKAGE-NAME" : "IOS-APP-ID",
  productionSecreteKey: Platform.isAndroid? "Android-Live-KEY" : "iOS-Live-KEY",
  sandBoxsecretKey: Platform.isAndroid?"Android-SANDBOX-KEY" : "iOS-SANDBOX-KEY",
  lang: "en");

Configure SDK Session Example

Future<void> setupSDKSession() async {
    try {
        trxMode: TransactionMode.PURCHASE,
        transactionCurrency: "kwd",
        amount: '100',
        customer: Customer(
              customerId: "", // customer id is important to retrieve cards saved for this customer
              email: "test@test.com",
              isdNumber: "965",
              number: "00000000",
              firstName: "test",
              middleName: "test",
              lastName: "test",
              metaData: null),
        paymentItems: <PaymentItem>[
                name: "item1",
                amountPerUnit: 1,
                quantity: Quantity(value: 1),
                discount: {
                "type": "F",
                "value": 10,
                "maximum_fee": 10,
                "minimum_fee": 1
                description: "Item 1 Apple",
                taxes: [
                    amount: Amount(
                        type: "F",
                        value: 10,
                        minimum_fee: 1,
                        maximum_fee: 10),
                    name: "tax1",
                    description: "tax description")
                totalAmount: 100),
        // List of taxes
        taxes: [
                amount: Amount(
                    type: "F", value: 10, minimum_fee: 1, maximum_fee: 10),
                name: "tax1",
                description: "tax description"),
                amount: Amount(
                    type: "F", value: 10, minimum_fee: 1, maximum_fee: 10),
                name: "tax1",
                description: "tax description")
        // List of shipping
        shippings: [
                name: "shipping 1",
                amount: 100,
                description: "shipping description 1"),
                name: "shipping 2",
                amount: 150,
                description: "shipping description 2")
        // Post URL
        postURL: "https://tap.company",
        // Payment description
        paymentDescription: "paymentDescription",
        // Payment Metadata
        paymentMetaData: {
            "a": "a meta",
            "b": "b meta",
        // Payment Reference
        paymentReference: Reference(
            acquirer: "acquirer",
            gateway: "gateway",
            payment: "payment",
            track: "track",
            transaction: "trans_910101",
            order: "order_262625"),
        // payment Descriptor
        paymentStatementDescriptor: "paymentStatementDescriptor",
        // Save Card Switch
        isUserAllowedToSaveCard: true,
        // Enable/Disable 3DSecure
        isRequires3DSecure: false,
        // Receipt SMS/Email
        receipt: Receipt(true, false),
        // Authorize Action [Capture - Void]
        authorizeAction: AuthorizeAction(
            type: AuthorizeActionType.CAPTURE, timeInHours: 10),
        // Destinations
            amount: 100,
            currency: 'kwd',
            count: 2,
            destinationlist: [
                    id: "",
                    amount: 100,
                    currency: "kwd",
                    description: "des",
                    reference: "ref_121299"),
                    id: "",
                    amount: 100,
                    currency: "kwd",
                    description: "des",
                   reference: "ref_22444444")
        // merchant id
        merchantID: "",
        // Allowed cards
        allowedCadTypes: CardType.ALL,
        applePayMerchantID: "merchant.applePayMerchantID",
        allowsToSaveSameCardMoreThanOnce: false,
        // pass the card holder name to the SDK
        cardHolderName: "Card Holder NAME",
        // disable changing the card holder name by the user
        allowsToEditCardHolderName: false,
        paymentType: PaymentType.ALL,
        sdkMode: SDKMode.Sandbox);
    } on PlatformException {

Transaction Modes

trxMode: TransactionMode.PURCHASE

You can set the transaction mode into one of the following modes:

  • Purchase
    • dart TransactionMode.PURCHASE

    Normal customer charge.

  • Authorize
    • dart TransactionMode.AUTHORIZE_CAPTURE

    Only authorization is happening. You should specify an action after successful authorization: either capture the amount or void the charge after specific period of time.

  • Save Card
    • dart TransactionMode.SAVE_CARD

    Use this mode to save the card of the customer with Tap and use it later.

  • Tokenize Card
    • dart TransactionMode.TOKENIZE_CARD

    Use this mode if you are willing to perform the charging/authorization manually. The purpose of this mode is only to collect and tokenize card information details of your customer if you don't have PCI compliance certificate but willing to process the payment manually using our services.

  • New Customer (First time to pay using goSell SDK)
  customerId: "",
  email: "test@test.com",
  isdNumber: "965",
  number: "00000000",
  firstName: "test",
  middleName: "test",
  lastName: "test",
  metaData: null)

After the first transaction success, you receive the customerId in the response. Save it to be used in the next transaction.

  • Existed Customer (paid before using goSell SDK) You need to set the customerId only and you can see the customer saved cards if the user has.
  customerId: "cus_smdnd3346nd3dks3jd9drd7d",
  email: "",
  isdNumber: "965",
  number: "00000000",
  firstName: "",
  middleName: "",
  lastName: "",
  metaData: null)

Please note that goSell SDK using the customerId only if it's not Empty ('').

Configure Payment Type

paymentType: PaymentType.ALL
Payment Type Description
ALL Shows all the available payment methods
CARD Shows only cards payment methods
DEVICE Shows payment methods depending on the device, for iOS it shows ApplePay only

Use Tap Pay Button

bottom: Platform.isIOS ? 0 : 10,
left: 18,
right: 18,
child: SizedBox(
height: 45,
child: ElevatedButton(
clipBehavior: Clip.hardEdge,
style: ButtonStyle(
backgroundColor: MaterialStateProperty.all(_buttonColor),
shape: MaterialStateProperty.all(
borderRadius: BorderRadius.circular(30),
onPressed: startSDK,
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
width: 25,
height: 25,
child: AwesomeLoader(
outerColor: Colors.white,
innerColor: Colors.white,
strokeWidth: 3.0,
controller: loaderController,
style: TextStyle(
color: Colors.white,
fontSize: 16.0,
color: Colors.white,

Handle SDK Result

  • Start SDK
   tapSDKResult = await GoSellSdkFlutter.startPaymentSDK;
  • Hnadle SDK result
setState(() {
switch (tapSDKResult['sdk_result']) {
case "SUCCESS":
sdkStatus = "SUCCESS";
case "FAILED":
sdkStatus = "FAILED";
case "SDK_ERROR":
sdkErrorCode                  = tapSDKResult['sdk_error_code'].toString();
sdkErrorMessage               = tapSDKResult['sdk_error_message'];
sdkErrorDescription           = tapSDKResult['sdk_error_description'];
sdkStatus = "NOT_IMPLEMENTED";
void handleSDKResult() {
  switch (tapSDKResult['trx_mode']) {
    case "CHARGE":
    case "AUTHORIZE":
    case "SAVE_CARD":
    case "TOKENIZE":
  token :                          =tapSDKResult['token'];
  token_currency                   =tapSDKResult['token_currency'];
  card_first_six                   =tapSDKResult['card_first_six'];
  card_last_four                   =tapSDKResult['card_last_four'];
  card_object                      =tapSDKResult['card_object'];
  card_exp_month                   =tapSDKResult['card_exp_month'];
  card_exp_year                    =tapSDKResult['card_exp_year'];
void extractSDKResultKeysAndValues() {
  id                             = tapSDKResult['charge_id'];
  description                    = tapSDKResult['description'];
  message                        = tapSDKResult['message'];
  card_first_six                 = tapSDKResult['card_first_six'];
  card_last_four                 = tapSDKResult['card_last_four'];
  card_object                    = tapSDKResult['card_object'];
  card_brand                     = tapSDKResult['card_brand'];
  card_exp_month                 = tapSDKResult['card_exp_month'];
  card_exp_year                  = tapSDKResult['card_exp_year'];
  acquirer_id                    = tapSDKResult['acquirer_id'];
  acquirer_response_code         = tapSDKResult['acquirer_response_code'];
  acquirer_response_message      = tapSDKResult['acquirer_response_message'];
  source_id                      = tapSDKResult['source_id'];
  source_channel                 = tapSDKResult['source_channel'];
  source_object                  = tapSDKResult['source_object'];
  source_payment_type            = tapSDKResult['source_payment_type'];
  responseID                     = tapSDKResult['charge_id'];

Apple pay setup

Follow the steps shared in the following link to setup apple pay: