package <%=packageName%>.security;

import <%=packageName%>.domain.User;
import <%=packageName%>.repository.UserRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Component;<% if (databaseType == 'sql') { %>
import org.springframework.transaction.annotation.Transactional;<%}%>

import java.util.*;
import java.util.stream.Collectors;

/**
 * Authenticate a user from the database.
 */
@Component("userDetailsService")
public class UserDetailsService implements org.springframework.security.core.userdetails.UserDetailsService {

    private final Logger log = LoggerFactory.getLogger(UserDetailsService.class);

    private final UserRepository userRepository;

    public UserDetailsService(UserRepository userRepository) {
        this.userRepository = userRepository;
    }

    @Override<% if (databaseType == 'sql') { %>
    @Transactional<%}%>
    public UserDetails loadUserByUsername(final String login) {
        log.debug("Authenticating {}", login);
        String lowercaseLogin = login.toLowerCase(Locale.ENGLISH);
        Optional<User> userFromDatabase = userRepository.findOneByLogin(lowercaseLogin);
        return userFromDatabase.map(user -> {
            if (!user.getActivated()) {
                throw new UserNotActivatedException("User " + lowercaseLogin + " was not activated");
            }
            List<GrantedAuthority> grantedAuthorities = user.getAuthorities().stream()<% if (databaseType == 'sql' || databaseType == 'mongodb') { %>
                    .map(authority -> new SimpleGrantedAuthority(authority.getName()))<% } %><% if (databaseType == 'cassandra') { %>
                .map(authority -> new SimpleGrantedAuthority(authority))<% } %>
                .collect(Collectors.toList());
            return new org.springframework.security.core.userdetails.User(lowercaseLogin,
                user.getPassword(),
                grantedAuthorities);
        }).orElseThrow(() -> new UsernameNotFoundException("User " + lowercaseLogin + " was not found in the " +
        "database"));
    }
}

package <%=packageName%>.security;

import <%=packageName%>.domain.User;
import <%=packageName%>.repository.UserRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Component;<% if (databaseType == 'sql') { %>
import org.springframework.transaction.annotation.Transactional;<%}%>

import java.util.*;
import java.util.stream.Collectors;

/**
 * Authenticate a user from the database.
 */
@Component("userDetailsService")
public class UserDetailsService implements org.springframework.security.core.userdetails.UserDetailsService {

    private final Logger log = LoggerFactory.getLogger(UserDetailsService.class);

    private final UserRepository userRepository;

    public UserDetailsService(UserRepository userRepository) {
        this.userRepository = userRepository;
    }

    @Override<% if (databaseType == 'sql') { %>
    @Transactional<%}%>
    public UserDetails loadUserByUsername(final String login) {
        log.debug("Authenticating {}", login);
        String lowercaseLogin = login.toLowerCase(Locale.ENGLISH);
        <%_ if (databaseType == 'sql') { _%>
        Optional<User> userFromDatabase = userRepository.findOneWithAuthoritiesByLogin(lowercaseLogin);
        <%_ } else { // MongoDB and Cassandra _%>
        Optional<User> userFromDatabase = userRepository.findOneByLogin(lowercaseLogin);
        <%_ } _%>
        return userFromDatabase.map(user -> {
            if (!user.getActivated()) {
                throw new UserNotActivatedException("User " + lowercaseLogin + " was not activated");
            }
            List<GrantedAuthority> grantedAuthorities = user.getAuthorities().stream()<% if (databaseType == 'sql' || databaseType == 'mongodb') { %>
                    .map(authority -> new SimpleGrantedAuthority(authority.getName()))<% } %><% if (databaseType == 'cassandra') { %>
                .map(authority -> new SimpleGrantedAuthority(authority))<% } %>
                .collect(Collectors.toList());
            return new org.springframework.security.core.userdetails.User(lowercaseLogin,
                user.getPassword(),
                grantedAuthorities);
        }).orElseThrow(() -> new UsernameNotFoundException("User " + lowercaseLogin + " was not found in the " +
        "database"));
    }
}

load user authorities eagerly in UserDetailsService