Add UserDetailsService implementation to use DB users

src/main/java/net/kapcake/bankingservice/config/BankingServiceConfig.java

@@ -2,13 +2,13 @@ package net.kapcake.bankingservice.config;
 
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.h2.tools.Server;
-import java.sql.SQLException;
+import org.springframework.security.crypto.factory.PasswordEncoderFactories;
+import org.springframework.security.crypto.password.PasswordEncoder;
 
 @Configuration
 public class BankingServiceConfig {
-    @Bean(initMethod = "start", destroyMethod = "stop")
-    public Server h2Server() throws SQLException {
-        return Server.createTcpServer("-tcp", "-tcpAllowOthers", "-tcpPort", "9092");
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        return PasswordEncoderFactories.createDelegatingPasswordEncoder();
     }
 }

src/main/java/net/kapcake/bankingservice/security/UserDetailsServiceImpl.java

@@ -0,0 +1,28 @@
+package net.kapcake.bankingservice.security;
+
+import net.kapcake.bankingservice.domain.User;
+import net.kapcake.bankingservice.repositories.UserRepository;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import static org.springframework.security.core.userdetails.User.withUsername;
+
+@Service
+public class UserDetailsServiceImpl implements UserDetailsService {
+    private final UserRepository userRepository;
+
+    public UserDetailsServiceImpl(UserRepository userRepository) {
+        this.userRepository = userRepository;
+    }
+
+    @Override
+    @Transactional
+    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
+        User user = userRepository.findByUsername(username)
+                .orElseThrow(() -> new UsernameNotFoundException("User (" + username + ") does not exist"));
+        return withUsername(username).password(user.getPassword()).authorities("USER").build();
+    }
+}