Package ch.nevis.mobile.sdk.api.operation.userverification

Interface FingerprintUserVerifier

public interface FingerprintUserVerifier
The object in charge of interacting with the user to do fingerprint authentication.

All the methods of the objects implementing this interface will be invoked in the main/UI thread.

The SDK does not provide implementations of this interface. The implementation must be done by the user of the SDK if the fingerprint authenticator is required.

See Also:

  • Method Details

    • verifyFingerprint

      void verifyFingerprint(FingerprintUserVerificationContext context, FingerprintUserVerificationHandler handler)
      The user verification interaction. In the case of the registration the user must provide credentials as required by the FIDO UAF protocol. In the case of the authentication, this is invoked for the user to provide credentials. If there is a recoverable error during the verification, this method will be invoked again, and the FingerprintUserVerificationContext.lastRecoverableError() will contain the error. The recoverable error can be used to inform the user of the recoverable error that occurred, because the UI is the responsibility of the developer using the SDK. The operation must be canceled. Basic implementation layout: 
       [...]

     @Override
     public void verifyFingerprint(FingerprintUserVerificationContext context, FingerprintUserVerificationHandler handler) {
         // Trigger the fingerprint authentication process. The handler can be used to cancel listening
         // for credentials
         OsAuthenticationListenHandler osAuthenticationListenHandler =
             handler.listenForOsCredentials();
         // Display a fingerprint screen asking the user to provide fingerprint credentials (so that the
         // user knows what to do)
     }
      Parameters:
      context - the object providing the information required for the verification process
      handler - the object that must be notified with the result of the interaction

    • onValidCredentialsProvided

      void onValidCredentialsProvided()
      This method is invoked when valid fingerprint credentials were provided and verified locally. The method is invoked after verifyFingerprint(FingerprintUserVerificationContext, FingerprintUserVerificationHandler) has been invoked and FingerprintUserVerificationHandler.listenForOsCredentials() is invoked in the FingerprintUserVerificationHandler of verifyUser and the end-user provides valid fingerprints.

      This method can be used for instance to hide the UI used to ask for credentials to the user (some screen asking the user to use the fingerprint sensor) and then display some progress message indicating that the operation is ongoing.

      Note that invoking this method does not mean that the UAF operation completed successfully (this is notified through methods such as Authentication.onSuccess(Consumer) or Registration.onSuccess(Runnable) once the FIDO UAF server validates the request generated with the credentials).