package org.apereo.cas.web.flow.authentication;
import org.apereo.cas.authentication.principal.Principal;
import org.apereo.cas.services.MultifactorAuthenticationProvider;
import org.apereo.cas.services.MultifactorAuthenticationProviderSelector;
import org.apereo.cas.services.RegisteredService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.OrderComparator;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
/**
* This is {@link RankedMultifactorAuthenticationProviderSelector}
* that sorts providers based on their rank and picks the one with
* the highest priority.
*
* @author Misagh Moayyed
* @since 5.0.0
*/
public class RankedMultifactorAuthenticationProviderSelector implements MultifactorAuthenticationProviderSelector {
private static final Logger LOGGER = LoggerFactory.getLogger(RankedMultifactorAuthenticationProviderSelector.class);
@Override
public MultifactorAuthenticationProvider resolve(final Collection<MultifactorAuthenticationProvider> providers,
final RegisteredService service, final Principal principal) {
final List<MultifactorAuthenticationProvider> sorted = new ArrayList<>(providers);
if (sorted.isEmpty()) {
throw new RuntimeException("List of candidate multifactor authentication providers is empty");
}
OrderComparator.sort(sorted);
final MultifactorAuthenticationProvider provider = sorted.get(sorted.size() - 1);
LOGGER.debug("Selected the provider [{}] for service [{}] out of [{}] providers", provider, service, providers.size());
return provider;
}
}