Cardlink Payments SDK for Android

Introduction

Cardlink Payments SDK for Android is a comprehensive, easy-to-integrate solution specifically designed for eCommerce applications on the Android platform. It aims to provide your customers with a smooth and secure transaction experience, while also offering developers a straightforward integration process. Also, it enables users to conveniently store their credit cards on secure Cardlink servers, allowing for seamless reuse without re-entering card information multiple times. As the cards are never retained on the user's device and encrypted card data is transmitted to the server only once, the SDK delivers heightened security while simultaneously enhancing user experience. Read on for more details on the integration process and sample code to get you started with the Cardlink Android Payments SDK. We look forward to making your eCommerce application more powerful, secure, and user-friendly.

Features

• Seamless Payment Processing: Effortlessly handle transactions ensuring an all-encompassing payment solution for your eCommerce application.
• Secure Storage: The Cardlink Payments SDK for Android allows users to securely store their credit card information on the protected Cardlink servers, enabling seamless reuse without the need for re-entering card details multiple times.
• Enhanced Security: With the Cardlink Payments SDK for Android, users' card data is never stored on their devices, and encrypted card information is transmitted to the server only once. This approach significantly heightens the security measures in place, safeguarding sensitive information.
• Optimized User Experience: By providing secure storage and seamless payment processing, the SDK ensures an improved user experience that minimizes friction during transactions and promotes customer satisfaction.
• Straightforward Integration: Designed with developers in mind, the Cardlink Payments SDK for Android offers a simple and efficient integration process, allowing you to quickly incorporate its features into your eCommerce application.

Requirements

Android API 26+

Installation via Gradle

Add repository

maven { url "https://maven.pkg.github.com/Cardlink-SA/Cardlink-payments-SDK-android-public" }

Add dependency to build.gradle:

implementation "gr.cardlink.payments:payments-sdk:1.x"

Usage

Follow these steps to start processing payments with Cardlink Android Payments SDK:

class App : Application() {
    override fun onCreate() {
        super.onCreate()
        PaymentsSdk.init(
            appContext = this,
            baseUrl = "https://baseUrl/",
            // optional headers param
            headers = mapOf(
                "Authorization" to "Bearer YourAuthToken",
                "Cookie" to "key=value"
            )
        )
    }
}

There is a convenient function PaymentsSdk.newIntent() that accepts as parameter a PaymentRequest object and launches the payment flow.

data class PaymentRequest(
    // Total amount in the smallest currency unit (eg. cents) 
    val paymentTotalCents: Long, 
    // Currency code (eg. EUR), or number (eg. 971) 
    val currencyCode: String,
    // Purchace description 
    val description: String, 
    // Address line 
    val addressLine: String,
    // City 
    val city: String,
    // Country code (eg. GR) or number (eg. 370) 
    val countryCode: String, 
    // Zip/postal code 
    val postalCode: String,
    // Recurring frequency
    val recurringFrequency: Int? = null,
    // Recurring end date with format YYYYMMDD. This is mandatory if recurringFrequency is present.
    val recurringEndDate: String? = null
)

Start activity for result. SDK will post back, with key PaymentActivity.KEY_PAYMENT_RESPONSE, the following response:

data class PaymentResponse( 
    val orderId: String?, 
    val transactionId: String?, 
    val errorCode: String?, 
    val description: String?, 
    val orderAmount: String?, 
    val paymentTotal: String?, 
    val currency: String?, 
    val paymentReference: String? 
) 

Example

// register for activity result
private val activityResultLauncher =
        registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {
            val paymentResponse = it.data?.getSerializableExtra(PaymentsSdk.KEY_PAYMENT_RESPONSE) as? PaymentResponse
            paymentResponse?.let { 
                // do something with response
            }
        }

private fun makePayment() {
    val paymentRequest = PaymentRequest(/* request params */)
    val intent = PaymentsSdk.newIntent(this, paymentRequest)
    activityResultLauncher.launch(intent)
}

Common error codes

Code	Description
error_network	network error
error_invalid_input	when request values are invalid
error_remote_encryption	remote encryption script failure
error_payment_methods	no valid payment methods available
error_accepted_card_types	no valid card types available

Currency

Specifying amounts

Currency amounts should be provided via the amount parameter as positive integers, representing how much to charge in the smallest currency unit (eg. 100 cents to charge €1.00, or 50050 cents to charge €500.50).

Specifying code/number

The three-letter currency code, as defined by ISO-4217, of the transaction, such as "EUR" for Euros, or the respective number "978".

Recurring payments

Recurring frequency

Indicates the frequency of recurring payments and defines the minimum number of days between two subsequent payments. 28 is special value indicating that transactions are to be initiated on monthly basis. Max value is 30.

Recurring end date

Recurring end date with format YYYYMMDD. This is mandatory if recurring frequency is present.

Flows

Successful payment flow (existing card)

Unsuccessful payment flow (existing card)

Payment with new card

Add card with NFC

Delete card

Instalments

License

Cardlink Payments SDK for Android is released under the MIT license. See LICENSE for details.