Added 'deleteUser' method

src/main/java/com/ceticamarco/bits/user/UserController.java

@@ -49,25 +49,23 @@ public class UserController {
                 : new ResponseEntity<>(res.getLeft().getMessage(), HttpStatus.BAD_REQUEST);
     }
 
-    /**
-     * Update an existing user
-     *
-     * @param user the user to update
-     * @return on failure, the error message
-     */
-    @PutMapping("/users")
-    public String updateUser(@RequestBody User user) {
-        return "";
-    }
-
     /**
      * Delete an existing user
      *
-     * @param userId the user ID to delete
+     * @param user the email and the password of the user
      * @return on failure, the error message
      */
-    @DeleteMapping("/users/{userId}")
-    public String deleteUser(@PathVariable("userId") Integer userId) {
-        return "";
+    @DeleteMapping("/users")
+    public ResponseEntity<String> deleteUser(@RequestBody User user) {
+        // Check if email and password are specified
+        if(user.getPassword() == null || user.getEmail() == null) {
+            return new ResponseEntity<>("Specify both email and password", HttpStatus.BAD_REQUEST);
+        }
+
+        // Delete the user
+        var res = userService.deleteUser(user);
+
+        return res.map(error -> new ResponseEntity<>(error.getMessage(), HttpStatus.BAD_REQUEST))
+                   .orElseGet(() -> new ResponseEntity<>("OK", HttpStatus.OK));
     }
 }

src/main/java/com/ceticamarco/bits/user/UserRepository.java

@@ -5,10 +5,15 @@ import org.springframework.data.jpa.repository.Query;
 
 import java.util.Optional;
 
-public interface UserRepository extends JpaRepository<User, Integer> {
+public interface UserRepository extends JpaRepository<User, String> {
     @Query("SELECT u FROM User u WHERE u.email = ?1")
     Optional<User> findUserByEmail(String email);
 
-    @Query("SELECT u FROM User u WHERE u.username= ?1")
+    @Query("SELECT u FROM User u WHERE u.username = ?1")
     Optional<User> findUserByUsername(String username);
+
+    @Query("SELECT u.password FROM User u WHERE u.email = ?1")
+    Optional<String> findPasswordByEmail(String email);
+    
+    void deleteUserByEmail(String email);
 }

src/main/java/com/ceticamarco/bits/user/UserService.java

@@ -1,10 +1,13 @@
 package com.ceticamarco.bits.user;
 
 import io.vavr.control.Either;
+import jakarta.transaction.Transactional;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
 
+import java.util.Optional;
+
 @Service
 public class UserService {
     private final UserRepository userRepository;
@@ -35,4 +38,26 @@ public class UserService {
 
         return Either.right(userId);
     }
+
+    @Transactional
+    public Optional<Error> deleteUser(User user) {
+        // Search user password by its email
+        var rawPassword = user.getPassword();
+        var encodedPassword = userRepository.findPasswordByEmail(user.getEmail());
+
+        // Check whether user exists
+        if(encodedPassword.isEmpty()) {
+            return Optional.of(new Error("Cannot find user."));
+        }
+
+        // Otherwise compare the hash
+        var isHashEqual = passwordEncoder.matches(rawPassword, encodedPassword.get());
+        if(!isHashEqual) {
+            return Optional.of(new Error("Wrong password."));
+        }
+
+        userRepository.deleteUserByEmail(user.getEmail());
+
+        return Optional.empty();
+    }
 }