Activate binding with app-to-app

The merchant application redirects the end user to the issuer application to approve the binding request. The approval decision comes from the issuer backend via VTS.

Device binding starts in the merchant application, but the final approval comes from the issuer backend.

Avoid device/server desynchronization. Activate the binding locally only after the token requestor is notified of success.

Flow

App-to-app device binding flow.

Step	Description
1	The end user selects the app-to-app option.
2	The decision is forwarded to Thales backend.
3	The merchant application redirects the end user to the issuer application.
4	The end user authenticates and validates the binding request in the issuer application.
5	The issuer accepts the binding request and informs VTS.
6-7	VTS notifies Thales backend to inform the merchant/PSP backend.
8	The merchant/PSP backend communicates the result to the merchant application.
9	The merchant application ends the pending binding session in the Thales SDK.

SDK integration

This page continues the flow after Create device binding (yellow flow).

1. Select the app-to-app ID&V method

During createBinding or resumeBinding, select the app-to-app ID&V method.

Android

Once the application submits the selected ID&V method successfully, the onIssuerAuthenticationReady callback will be returned to the application. Otherwise, an onError callback will be returned.

@Override
public void onIssuerAuthenticationRequired(IDVSession idvSession) { 
    // Submit APP_TO_APP ID&V Method
    for (IDVMethod idvMethod : idvSession.getIdvMethods()) {
        if (idvMethod.getType().equals(IDVType.APP_TO_APP)) {
            idvSession.selectIdvMethod(idvMethod);
        }
    }
}

@Override
public void onIssuerAuthenticationReady(IDVSession idvSession, 
                                        @Nullable OtpActivationStatus status) {
    
}

@Override
public void onError(TMGClientException exception) { 
    // Check if there's any error
    int errorCode = exception.getErrorCode();
    int errorMessage = exception.getMessage();
}

iOS

guard let idvSession = VisaService.shared.idvSession else {
    // No IDV session.
    return
}
// 1. Display list of IDV methods.
do {
    let idvMethods = try idvSession.idvMethods
    let selectedIdvMethod = idvMethods[0] // user select an app to app idv method
    
    // 2. Submit the IDV method.
    idvSession.selectIDVMethod(selectedIdvMethod) { (result) in
        if let otpActivationStatus = result {
        
        } else {
            if selectedIdvMethod.type == .appToApp {
                let idvType = selectedIdvMethod.type
                let requestPayload = selectedIdvMethod.requestPayload
                let source = selectedIdvMethod.source
                let value = selectedIdvMethod.value
                // 3. Launch an app.
            }
        }
    }
} catch let error {
    // Handles the error.
}

// 4. Failure in step 2, selectIDVMethod, will be handled in completionHandler.
VisaService.shared.completionHandler = { (session, error) in
    // 5. Check if it is a selectIDVMethod error.
    if let session = session,
        let error = error,
        error.description == TMGError.invalidIdvMethod.description {
        VisaService.shared.idvSession = session
        // 6. Retry the IDV flow.
    }
}

2. Get app-to-app redirection data

Your merchant application must handle the app-to-app redirect. This is outside the scope of the Thales SDK.

Android

The merchant application can use the deep link mechanism to launch the issuer application. The data needed for binding activation can be retrieved from the IDVMethod object.

// Gets the additional data for app to app.
IDVType idvType = idvMethod.getType();
String requestPayload = idvMethod.getRequestPayload();
String source = idvMethod.getSource();
String value = idvMethod.getValue();

iOS

The merchant application can use URL Schemes or Universal Links to launch the issuer application. The data needed for binding activation can be retrieved from the IDVMethod object.

let idvType = selectedIdvMethod.type
let requestPayload = selectedIdvMethod.requestPayload
let source = selectedIdvMethod.source
let value = selectedIdvMethod.value

3. Activate the binding

After the end user returns from the issuer application, wait for your merchant or PSP backend to confirm approval. Then activate the binding locally by calling activateBinding on the IDVSession object.

Pass null to indicate the flow is complete.

Android

@Override
public void onIssuerAuthenticationReady(IDVSession idvSession, 
                                        @Nullable OtpActivationStatus status) { 
    // Activate binding locally
    idvSession.activateBinding(null);
}

@Override
public void onError(TMGClientException exception) { 
    // Check if there is any error
    int errorCode = exception.getErrorCode();
    int errorMessage = exception.getMessage();
}

The result of activating the binding process is returned via the onSuccess callback function or onError if there is an error.

iOS

guard let idvSession = VisaService.shared.idvSession else {
    // No IDV session.
    return
}
// 1. Call activate after the end user return from app
idvSession.activateBinding(withValue: nil)

VisaService.shared.completionHandler = { (session, error) in
    // 2. Check if it is a activateBinding success.
    if error == nil {
        
    }
}

The result of activating the binding process is returned via the completionHandler callback function. In cases where the binding activation fails, completionHandler will be called and an IDVSession object together with an error object will be passed to the end user to retry the process.