48. User registration - Implementation (#4)

support-portal-backend/src/main/java/net/shyshkin/study/fullstack/supportportal/backend/repository/UserRepository.java

@@ -9,6 +9,10 @@ public interface UserRepository extends JpaRepository<User, Long> {
 
     Optional<User> findByUsername(String username);
 
-    Optional<User> findAllByEmail(String email);
+    Optional<User> findByEmail(String email);
+
+    Boolean existsByUsername(String username);
+
+    Boolean existsByEmail(String email);
 
 }

support-portal-backend/src/main/java/net/shyshkin/study/fullstack/supportportal/backend/service/UserServiceImpl.java

@@ -1,21 +1,35 @@
 package net.shyshkin.study.fullstack.supportportal.backend.service;
 
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import net.shyshkin.study.fullstack.supportportal.backend.domain.Role;
 import net.shyshkin.study.fullstack.supportportal.backend.domain.User;
 import net.shyshkin.study.fullstack.supportportal.backend.domain.UserPrincipal;
+import net.shyshkin.study.fullstack.supportportal.backend.exception.domain.EmailExistsException;
+import net.shyshkin.study.fullstack.supportportal.backend.exception.domain.EmailNotFoundException;
+import net.shyshkin.study.fullstack.supportportal.backend.exception.domain.UserNotFoundException;
+import net.shyshkin.study.fullstack.supportportal.backend.exception.domain.UsernameExistsException;
 import net.shyshkin.study.fullstack.supportportal.backend.repository.UserRepository;
+import org.apache.commons.lang3.RandomStringUtils;
 import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
+import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
 
 import javax.transaction.Transactional;
 import java.time.LocalDateTime;
+import java.util.List;
+import java.util.Objects;
+import java.util.UUID;
 
+@Slf4j
 @Service
 @RequiredArgsConstructor
 public class UserServiceImpl implements UserService {
 
     private final UserRepository userRepository;
+    private final PasswordEncoder passwordEncoder;
 
     @Override
     @Transactional
@@ -27,4 +41,97 @@ public class UserServiceImpl implements UserService {
         user.setLastLoginDate(LocalDateTime.now());
         return new UserPrincipal(user);
     }
+
+    @Override
+    public User register(String firstName, String lastName, String username, String email) {
+
+        validateNewUsernameAndEmail(username, email);
+
+        Role defaultRole = Role.ROLE_USER;
+
+        String rawPassword = generatePassword();
+        String encodedPassword = passwordEncoder.encode(rawPassword);
+        log.debug("Raw password: {}. Encoded password: {}", rawPassword, encodedPassword);
+
+        User newUser = User.builder()
+                .email(email)
+                .firstName(firstName)
+                .lastName(lastName)
+                .username(username)
+                .password(encodedPassword)
+                .userId(generateUserId())
+                .isActive(true)
+                .isNotLocked(true)
+                .joinDate(LocalDateTime.now())
+                .profileImageUrl(getTemporaryProfileImageUrl())
+                .lastLoginDate(null)
+                .lastLoginDateDisplay(null)
+                .role(defaultRole.name())
+                .authorities(defaultRole.getAuthorities())
+                .build();
+        return userRepository.save(newUser);
+    }
+
+    private String getTemporaryProfileImageUrl() {
+        return ServletUriComponentsBuilder.fromCurrentContextPath().path("/user/image/profile/temp").build().toString();
+    }
+
+    private String generatePassword() {
+        return RandomStringUtils.randomAscii(10);
+    }
+
+    private String generateUserId() {
+        return UUID.randomUUID().toString();
+    }
+
+    @Override
+    public List<User> findAll() {
+        return userRepository.findAll();
+    }
+
+    @Override
+    public User findByUsername(String username) {
+        return userRepository
+                .findByUsername(username)
+                .orElseThrow(() -> new UserNotFoundException("User with username `" + username + "` not found"));
+    }
+
+    @Override
+    public User findByEmail(String email) {
+        return userRepository
+                .findByEmail(email)
+                .orElseThrow(() -> new EmailNotFoundException("User with email `" + email + "` not found"));
+    }
+
+    private void validateNewUsernameAndEmail(String username, String email) {
+
+        if (userRepository.existsByUsername(username))
+            throwUsernameExistsException(username);
+
+        if (userRepository.existsByEmail(email))
+            throwEmailExistsException(email);
+    }
+
+    private User validateUpdateUsernameAndEmail(String currentUsername, String username, String email) {
+
+        Objects.requireNonNull(currentUsername);
+
+        User currentUser = findByUsername(currentUsername);
+
+        if (!Objects.equals(currentUsername, username) && userRepository.existsByUsername(username))
+            throwUsernameExistsException(username);
+
+        if (!Objects.equals(currentUser.getEmail(), email) && userRepository.existsByEmail(email))
+            throwEmailExistsException(email);
+
+        return currentUser;
+    }
+
+    private void throwEmailExistsException(String email) {
+        throw new EmailExistsException("User with email `" + email + "` is already registered");
+    }
+
+    private void throwUsernameExistsException(String username) {
+        throw new UsernameExistsException("Username `" + username + "` is already taken. Please select another one");
+    }
 }