Class BiometricUserVerifierAbstract

The user verification interaction.

In the case of the registration the user must provide credentials again as required by the FIDO UAF protocol. In the case of the authentication, this is invoked for the user to provide credentials. In the case of the biometric authenticator, since the UI management is delegated to the operating system, the verifyBiometric method will not be invoked when a recoverable error occurs: the operating system will inform the end-user of the problem that happened. This implies that verifyBiometric is only invoked once when using the biometric authenticator.

This method is invoked when either valid biometric credentials were provided and verified locally.

The method is invoked after verifyBiometric has been invoked and BiometricUserVerificationHandler.listenForOsCredentials is invoked in the BiometricUserVerificationHandler of verifyBiometric and the end-user provides valid biometric credentials.

This method can be used for instance to 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 onSuccess methods once the FIDO UAF server validates the request generated with the credentials).

If the user provided invalid credentials, and we are in the context of a recoverable error, then verifyBiometric will be invoked again. If it is a non-recoverable error, then the onError method will be invoked.