비밀번호 변경 구현

src/main/java/com/example/daemawiki/domain/user/dto/ChangePasswordRequest.java

@@ -0,0 +1,7 @@
+package com.example.daemawiki.domain.user.dto;
+
+public record ChangePasswordRequest(
+        String oldPassword,
+        String newPassword
+) {
+}

src/main/java/com/example/daemawiki/domain/user/model/User.java

@@ -44,4 +44,8 @@ public void editDetail(UserDetail detail) {
         this.detail = detail;
     }
 
+    public void changePassword(String password) {
+        this.password = password;
+    }
+
 }

src/main/java/com/example/daemawiki/domain/user/service/ChangePassword.java

@@ -0,0 +1,34 @@
+package com.example.daemawiki.domain.user.service;
+
+import com.example.daemawiki.domain.user.dto.ChangePasswordRequest;
+import com.example.daemawiki.domain.user.repository.UserRepository;
+import com.example.daemawiki.domain.user.service.facade.UserFacade;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Mono;
+
+@Service
+public class ChangePassword {
+    private final PasswordEncoder passwordEncoder;
+    private final UserFacade userFacade;
+    private final UserRepository userRepository;
+
+    public ChangePassword(PasswordEncoder passwordEncoder, UserFacade userFacade, UserRepository userRepository) {
+        this.passwordEncoder = passwordEncoder;
+        this.userFacade = userFacade;
+        this.userRepository = userRepository;
+    }
+
+    public Mono<Void> execute(ChangePasswordRequest request) {
+        return userFacade.currentUser()
+                .filter(user -> passwordEncoder.matches(request.oldPassword(), user.getPassword()))
+                .switchIfEmpty(Mono.error(new RuntimeException()))
+                .map(user -> {
+                    user.changePassword(passwordEncoder.encode(request.newPassword()));
+                    return user;
+                })
+                .flatMap(userRepository::save)
+                .then();
+    }
+
+}