From e1545d3e3f0666ea48cb6bcec10db84b69d808c3 Mon Sep 17 00:00:00 2001
From: Shin-Yun-Cheol <yptlsdbscjf@naver.com>
Date: Tue, 30 Sep 2025 16:49:17 +0900
Subject: [PATCH 1/5] =?UTF-8?q?chore=20:=20=EC=9D=B4=EC=8A=88=20=EC=83=9D?=
 =?UTF-8?q?=EC=84=B1=20=ED=85=9C=ED=94=8C=EB=A6=BF=20=EC=9E=91=EC=84=B1?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/ISSUE_TEMPLATE/refact_request.md | 16 ++++++++++++++++
 .idea/gradle.xml                         |  1 +
 2 files changed, 17 insertions(+)
 create mode 100644 .github/ISSUE_TEMPLATE/refact_request.md

diff --git a/.github/ISSUE_TEMPLATE/refact_request.md b/.github/ISSUE_TEMPLATE/refact_request.md
new file mode 100644
index 0000000..65b132b
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/refact_request.md
@@ -0,0 +1,16 @@
+---
+name: "Refact Report"
+about: 버그 리포트를 작성할 때 사용하는 템플릿입니다.
+title: "[REFACT] "
+labels: "refact"
+assignees: ''
+---
+
+### 🔬 재현 절차
+1. ...
+2. ...
+3. ...
+
+### 🤔 예상 결과
+### 💻 환경
+- **OS:** - **Browser:**
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
index 14746e7..2a65317 100644
--- a/.idea/gradle.xml
+++ b/.idea/gradle.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>

From cadaeae817c2118db413b24e51189eaf7e843553 Mon Sep 17 00:00:00 2001
From: Shin-Yun-Cheol <yptlsdbscjf@naver.com>
Date: Tue, 30 Sep 2025 22:07:12 +0900
Subject: [PATCH 2/5] =?UTF-8?q?[#2];=20refactor=20:=204=EA=B3=84=EC=B8=B5?=
 =?UTF-8?q?=20=EC=A0=81=EC=9A=A9=20-=20application,=20business,=20implemen?=
 =?UTF-8?q?t,=20repository=EB=A1=9C=20=ED=81=AC=EA=B2=8C=204=EA=B3=84?=
 =?UTF-8?q?=EC=B8=B5=EC=9D=84=20=EC=A0=81=EC=9A=A9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../mission/controller/HomeController.java    | 12 -----------
 .../{ => application}/PostController.java     |  3 ++-
 .../mission/post/business/PostService.java    | 11 ++++++++++
 .../java/mission/post/{ => domain}/Post.java  |  4 ++--
 .../PostServiceImpl.java}                     | 21 ++++++++++++-------
 .../post/{ => repository}/PostRepository.java |  3 ++-
 .../{ => application}/UserController.java     |  7 ++++---
 .../mission/user/business/UserService.java    |  8 +++++++
 .../java/mission/user/{ => domain}/User.java  |  2 +-
 .../UserServiceImpl.java}                     |  8 +++++--
 .../user/{ => repository}/UserRepository.java |  3 ++-
 11 files changed, 51 insertions(+), 31 deletions(-)
 delete mode 100644 src/main/java/mission/controller/HomeController.java
 rename src/main/java/mission/post/{ => application}/PostController.java (93%)
 create mode 100644 src/main/java/mission/post/business/PostService.java
 rename src/main/java/mission/post/{ => domain}/Post.java (91%)
 rename src/main/java/mission/post/{PostService.java => implement/PostServiceImpl.java} (79%)
 rename src/main/java/mission/post/{ => repository}/PostRepository.java (66%)
 rename src/main/java/mission/user/{ => application}/UserController.java (76%)
 create mode 100644 src/main/java/mission/user/business/UserService.java
 rename src/main/java/mission/user/{ => domain}/User.java (95%)
 rename src/main/java/mission/user/{UserService.java => implement/UserServiceImpl.java} (82%)
 rename src/main/java/mission/user/{ => repository}/UserRepository.java (78%)

diff --git a/src/main/java/mission/controller/HomeController.java b/src/main/java/mission/controller/HomeController.java
deleted file mode 100644
index 4b578de..0000000
--- a/src/main/java/mission/controller/HomeController.java
+++ /dev/null
@@ -1,12 +0,0 @@
-package mission.controller;
-
-import org.springframework.web.bind.annotation.GetMapping;
-import org.springframework.web.bind.annotation.RestController;
-
-@RestController
-public class HomeController {
-    @GetMapping("/ping")
-    public String ping() {
-        return "ok";
-    }
-}
diff --git a/src/main/java/mission/post/PostController.java b/src/main/java/mission/post/application/PostController.java
similarity index 93%
rename from src/main/java/mission/post/PostController.java
rename to src/main/java/mission/post/application/PostController.java
index 3ec5956..98d9d74 100644
--- a/src/main/java/mission/post/PostController.java
+++ b/src/main/java/mission/post/application/PostController.java
@@ -1,10 +1,11 @@
-package mission.post;
+package mission.post.application;
 
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 import mission.post.dto.CreatePostRequest;
 import mission.post.dto.PostCreateResponse;
 import mission.post.dto.UpdatePostRequest;
+import mission.post.business.PostService;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 
diff --git a/src/main/java/mission/post/business/PostService.java b/src/main/java/mission/post/business/PostService.java
new file mode 100644
index 0000000..718f0e4
--- /dev/null
+++ b/src/main/java/mission/post/business/PostService.java
@@ -0,0 +1,11 @@
+package mission.post.business;
+
+import mission.post.dto.CreatePostRequest;
+import mission.post.dto.PostCreateResponse;
+import mission.post.dto.UpdatePostRequest;
+
+public interface PostService {
+    PostCreateResponse create(CreatePostRequest request);
+    PostCreateResponse update(Long id, UpdatePostRequest request);
+    void delete(Long id, String email, String password);
+}
diff --git a/src/main/java/mission/post/Post.java b/src/main/java/mission/post/domain/Post.java
similarity index 91%
rename from src/main/java/mission/post/Post.java
rename to src/main/java/mission/post/domain/Post.java
index c24f765..99e9e51 100644
--- a/src/main/java/mission/post/Post.java
+++ b/src/main/java/mission/post/domain/Post.java
@@ -1,9 +1,9 @@
-package mission.post;
+package mission.post.domain;
 
 import jakarta.persistence.*;
 import jakarta.validation.constraints.NotBlank;
 import lombok.*;
-import mission.user.User;
+import mission.user.domain.User;
 
 @Entity
 @Table(name = "post")
diff --git a/src/main/java/mission/post/PostService.java b/src/main/java/mission/post/implement/PostServiceImpl.java
similarity index 79%
rename from src/main/java/mission/post/PostService.java
rename to src/main/java/mission/post/implement/PostServiceImpl.java
index 2c42b9e..803d652 100644
--- a/src/main/java/mission/post/PostService.java
+++ b/src/main/java/mission/post/implement/PostServiceImpl.java
@@ -1,21 +1,25 @@
-package mission.post;
+package mission.post.implement;
 
 import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
+import mission.post.domain.Post;
+import mission.post.repository.PostRepository;
 import mission.post.dto.CreatePostRequest;
 import mission.post.dto.PostCreateResponse;
 import mission.post.dto.UpdatePostRequest;
-import mission.user.User;
-import mission.user.UserRepository;
+import mission.post.business.PostService;
+import mission.user.domain.User;
+import mission.user.repository.UserRepository;
 import org.springframework.security.crypto.bcrypt.BCrypt;
 import org.springframework.stereotype.Service;
 
 @Service
 @RequiredArgsConstructor
-public class PostService {
+public class PostServiceImpl implements PostService {
     private final PostRepository postRepository;
     private final UserRepository userRepository;
 
+    @Override
     @Transactional
     public PostCreateResponse create(CreatePostRequest createPostRequest) {
         User author = userRepository.findByEmail(createPostRequest.email())
@@ -34,16 +38,17 @@ public PostCreateResponse create(CreatePostRequest createPostRequest) {
         return new PostCreateResponse(saved.getId(), author.getEmail(), saved.getTitle(), saved.getContent());
     }
 
+    @Override
     @Transactional
-    public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequeset){
+    public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
         Post post = postRepository.findById(id)
                 .orElseThrow(()->new IllegalArgumentException("post not found"));
 
-        if(!post.getAuthor().getEmail().equals(updatePostRequeset.email()) || !BCrypt.checkpw(updatePostRequeset.password(), post.getAuthor().getPasswordHash())){
+        if(!post.getAuthor().getEmail().equals(updatePostRequest.email()) || !BCrypt.checkpw(updatePostRequest.password(), post.getAuthor().getPasswordHash())){
             throw new IllegalArgumentException("email or password does not match");
         }
 
-        post.edit(updatePostRequeset.title(), updatePostRequeset.content());
+        post.edit(updatePostRequest.title(), updatePostRequest.content());
 
         return new PostCreateResponse(
                 post.getId(),
@@ -52,7 +57,7 @@ public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequeset){
                 post.getContent()
         );
     }
-
+    @Override
     @Transactional
     public void delete(Long id, String email, String password){
         Post post = postRepository.findById(id)
diff --git a/src/main/java/mission/post/PostRepository.java b/src/main/java/mission/post/repository/PostRepository.java
similarity index 66%
rename from src/main/java/mission/post/PostRepository.java
rename to src/main/java/mission/post/repository/PostRepository.java
index bd9c4ca..81d03cd 100644
--- a/src/main/java/mission/post/PostRepository.java
+++ b/src/main/java/mission/post/repository/PostRepository.java
@@ -1,5 +1,6 @@
-package mission.post;
+package mission.post.repository;
 
+import mission.post.domain.Post;
 import org.springframework.data.jpa.repository.JpaRepository;
 
 public interface PostRepository extends JpaRepository<Post, Long> {
diff --git a/src/main/java/mission/user/UserController.java b/src/main/java/mission/user/application/UserController.java
similarity index 76%
rename from src/main/java/mission/user/UserController.java
rename to src/main/java/mission/user/application/UserController.java
index 627d35f..f32fbbc 100644
--- a/src/main/java/mission/user/UserController.java
+++ b/src/main/java/mission/user/application/UserController.java
@@ -1,6 +1,7 @@
-package mission.user;
+package mission.user.application;
 
 import lombok.RequiredArgsConstructor;
+import mission.user.implement.UserServiceImpl;
 import mission.user.dto.SignUpRequest;
 import mission.user.dto.SignUpResponse;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -13,10 +14,10 @@
 @RequiredArgsConstructor
 public class UserController {
 
-    private final UserService userService;
+    private final UserServiceImpl userServiceImpl;
 
     @PostMapping("/signup")
     public SignUpResponse signup(@RequestBody SignUpRequest request){
-        return userService.signup(request);
+        return userServiceImpl.signup(request);
     }
 }
diff --git a/src/main/java/mission/user/business/UserService.java b/src/main/java/mission/user/business/UserService.java
new file mode 100644
index 0000000..12d451b
--- /dev/null
+++ b/src/main/java/mission/user/business/UserService.java
@@ -0,0 +1,8 @@
+package mission.user.business;
+
+import mission.user.dto.SignUpRequest;
+import mission.user.dto.SignUpResponse;
+
+public interface UserService {
+    SignUpResponse signup(SignUpRequest signUpRequest);
+}
diff --git a/src/main/java/mission/user/User.java b/src/main/java/mission/user/domain/User.java
similarity index 95%
rename from src/main/java/mission/user/User.java
rename to src/main/java/mission/user/domain/User.java
index 062f9b6..a7ece49 100644
--- a/src/main/java/mission/user/User.java
+++ b/src/main/java/mission/user/domain/User.java
@@ -1,4 +1,4 @@
-package mission.user;
+package mission.user.domain;
 
 import jakarta.persistence.*;
 import jakarta.validation.constraints.Email;
diff --git a/src/main/java/mission/user/UserService.java b/src/main/java/mission/user/implement/UserServiceImpl.java
similarity index 82%
rename from src/main/java/mission/user/UserService.java
rename to src/main/java/mission/user/implement/UserServiceImpl.java
index e044b91..b69e774 100644
--- a/src/main/java/mission/user/UserService.java
+++ b/src/main/java/mission/user/implement/UserServiceImpl.java
@@ -1,17 +1,21 @@
-package mission.user;
+package mission.user.implement;
 
 import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
+import mission.user.domain.User;
 import mission.user.dto.SignUpRequest;
 import mission.user.dto.SignUpResponse;
+import mission.user.repository.UserRepository;
+import mission.user.business.UserService;
 import org.springframework.security.crypto.bcrypt.BCrypt;
 import org.springframework.stereotype.Service;
 
 @Service
 @RequiredArgsConstructor
-public class UserService {
+public class UserServiceImpl implements UserService {
     private final UserRepository userRepository;
 
+    @Override
     @Transactional
     public SignUpResponse signup(SignUpRequest signUpRequest) {
         if(userRepository.existsByEmail(signUpRequest.email())){
diff --git a/src/main/java/mission/user/UserRepository.java b/src/main/java/mission/user/repository/UserRepository.java
similarity index 78%
rename from src/main/java/mission/user/UserRepository.java
rename to src/main/java/mission/user/repository/UserRepository.java
index e15b698..e3d979a 100644
--- a/src/main/java/mission/user/UserRepository.java
+++ b/src/main/java/mission/user/repository/UserRepository.java
@@ -1,5 +1,6 @@
-package mission.user;
+package mission.user.repository;
 
+import mission.user.domain.User;
 import org.springframework.data.jpa.repository.JpaRepository;
 import java.util.Optional;
 

From 009011098e4ecfa818d1ac70b87aab6e1e279266 Mon Sep 17 00:00:00 2001
From: Shin-Yun-Cheol <yptlsdbscjf@naver.com>
Date: Tue, 30 Sep 2025 22:23:57 +0900
Subject: [PATCH 3/5] =?UTF-8?q?[#3];=20refactor=20:=204=EA=B3=84=EC=B8=B5?=
 =?UTF-8?q?=20=EC=A0=81=EC=9A=A9=20=EC=88=98=EC=A0=95=20-=20business=20?=
 =?UTF-8?q?=EC=9D=98=20service=EB=A5=BC=20=EA=B5=B3=EC=9D=B4=20impl?=
 =?UTF-8?q?=EA=B3=BC=20=EB=82=98=EB=88=84=EC=A7=80=20=EC=95=8A=EC=95=84?=
 =?UTF-8?q?=EB=8F=84=20=EB=90=A0=20=EA=B2=83=20=EA=B0=99=EC=95=84=EC=84=9C?=
 =?UTF-8?q?=20=EB=8B=A4=EC=8B=9C=20=EB=B3=80=EA=B2=BD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../post/application/PostController.java      |  2 +-
 .../mission/post/business/PostService.java    | 66 +++++++++++++++--
 .../post/implement/PostServiceImpl.java       | 72 -------------------
 .../user/application/UserController.java      |  6 +-
 .../mission/user/business/UserService.java    | 29 +++++++-
 .../user/implement/UserServiceImpl.java       | 35 ---------
 6 files changed, 93 insertions(+), 117 deletions(-)
 delete mode 100644 src/main/java/mission/post/implement/PostServiceImpl.java
 delete mode 100644 src/main/java/mission/user/implement/UserServiceImpl.java

diff --git a/src/main/java/mission/post/application/PostController.java b/src/main/java/mission/post/application/PostController.java
index 98d9d74..70ff11a 100644
--- a/src/main/java/mission/post/application/PostController.java
+++ b/src/main/java/mission/post/application/PostController.java
@@ -2,10 +2,10 @@
 
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
+import mission.post.business.PostService;
 import mission.post.dto.CreatePostRequest;
 import mission.post.dto.PostCreateResponse;
 import mission.post.dto.UpdatePostRequest;
-import mission.post.business.PostService;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 
diff --git a/src/main/java/mission/post/business/PostService.java b/src/main/java/mission/post/business/PostService.java
index 718f0e4..f077815 100644
--- a/src/main/java/mission/post/business/PostService.java
+++ b/src/main/java/mission/post/business/PostService.java
@@ -1,11 +1,69 @@
 package mission.post.business;
 
+import jakarta.transaction.Transactional;
+import lombok.RequiredArgsConstructor;
+import mission.post.domain.Post;
+import mission.post.repository.PostRepository;
 import mission.post.dto.CreatePostRequest;
 import mission.post.dto.PostCreateResponse;
 import mission.post.dto.UpdatePostRequest;
+import mission.user.domain.User;
+import mission.user.repository.UserRepository;
+import org.springframework.security.crypto.bcrypt.BCrypt;
+import org.springframework.stereotype.Service;
 
-public interface PostService {
-    PostCreateResponse create(CreatePostRequest request);
-    PostCreateResponse update(Long id, UpdatePostRequest request);
-    void delete(Long id, String email, String password);
+@Service
+@RequiredArgsConstructor
+public class PostService {
+    private final PostRepository postRepository;
+    private final UserRepository userRepository;
+
+
+    @Transactional
+    public PostCreateResponse create(CreatePostRequest createPostRequest) {
+        User author = userRepository.findByEmail(createPostRequest.email())
+                .orElseThrow(()->new IllegalArgumentException("email or password not found"));
+        if (!BCrypt.checkpw(createPostRequest.password(), author.getPasswordHash()))
+            throw new IllegalArgumentException("email or password does not match");
+
+        Post saved = postRepository.save(
+                Post.builder()
+                        .title(createPostRequest.title())
+                        .content(createPostRequest.content())
+                        .author(author)
+                        .build()
+        );
+
+        return new PostCreateResponse(saved.getId(), author.getEmail(), saved.getTitle(), saved.getContent());
+    }
+
+    @Transactional
+    public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
+        Post post = postRepository.findById(id)
+                .orElseThrow(()->new IllegalArgumentException("post not found"));
+
+        if(!post.getAuthor().getEmail().equals(updatePostRequest.email()) || !BCrypt.checkpw(updatePostRequest.password(), post.getAuthor().getPasswordHash())){
+            throw new IllegalArgumentException("email or password does not match");
+        }
+
+        post.edit(updatePostRequest.title(), updatePostRequest.content());
+
+        return new PostCreateResponse(
+                post.getId(),
+                post.getAuthor().getEmail(),
+                post.getTitle(),
+                post.getContent()
+        );
+    }
+    @Transactional
+    public void delete(Long id, String email, String password){
+        Post post = postRepository.findById(id)
+                .orElseThrow(()->new IllegalArgumentException("post not found"));
+
+        if(!post.getAuthor().getEmail().equals(email) || !BCrypt.checkpw(password, post.getAuthor().getPasswordHash())){
+            throw new IllegalArgumentException("email or password does not match");
+        }
+
+        postRepository.delete(post);
+    }
 }
diff --git a/src/main/java/mission/post/implement/PostServiceImpl.java b/src/main/java/mission/post/implement/PostServiceImpl.java
deleted file mode 100644
index 803d652..0000000
--- a/src/main/java/mission/post/implement/PostServiceImpl.java
+++ /dev/null
@@ -1,72 +0,0 @@
-package mission.post.implement;
-
-import jakarta.transaction.Transactional;
-import lombok.RequiredArgsConstructor;
-import mission.post.domain.Post;
-import mission.post.repository.PostRepository;
-import mission.post.dto.CreatePostRequest;
-import mission.post.dto.PostCreateResponse;
-import mission.post.dto.UpdatePostRequest;
-import mission.post.business.PostService;
-import mission.user.domain.User;
-import mission.user.repository.UserRepository;
-import org.springframework.security.crypto.bcrypt.BCrypt;
-import org.springframework.stereotype.Service;
-
-@Service
-@RequiredArgsConstructor
-public class PostServiceImpl implements PostService {
-    private final PostRepository postRepository;
-    private final UserRepository userRepository;
-
-    @Override
-    @Transactional
-    public PostCreateResponse create(CreatePostRequest createPostRequest) {
-        User author = userRepository.findByEmail(createPostRequest.email())
-                .orElseThrow(()->new IllegalArgumentException("email or password not found"));
-        if (!BCrypt.checkpw(createPostRequest.password(), author.getPasswordHash()))
-            throw new IllegalArgumentException("email or password does not match");
-
-        Post saved = postRepository.save(
-                Post.builder()
-                        .title(createPostRequest.title())
-                        .content(createPostRequest.content())
-                        .author(author)
-                        .build()
-        );
-
-        return new PostCreateResponse(saved.getId(), author.getEmail(), saved.getTitle(), saved.getContent());
-    }
-
-    @Override
-    @Transactional
-    public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
-        Post post = postRepository.findById(id)
-                .orElseThrow(()->new IllegalArgumentException("post not found"));
-
-        if(!post.getAuthor().getEmail().equals(updatePostRequest.email()) || !BCrypt.checkpw(updatePostRequest.password(), post.getAuthor().getPasswordHash())){
-            throw new IllegalArgumentException("email or password does not match");
-        }
-
-        post.edit(updatePostRequest.title(), updatePostRequest.content());
-
-        return new PostCreateResponse(
-                post.getId(),
-                post.getAuthor().getEmail(),
-                post.getTitle(),
-                post.getContent()
-        );
-    }
-    @Override
-    @Transactional
-    public void delete(Long id, String email, String password){
-        Post post = postRepository.findById(id)
-                .orElseThrow(()->new IllegalArgumentException("post not found"));
-
-        if(!post.getAuthor().getEmail().equals(email) || !BCrypt.checkpw(password, post.getAuthor().getPasswordHash())){
-            throw new IllegalArgumentException("email or password does not match");
-        }
-
-        postRepository.delete(post);
-    }
-}
diff --git a/src/main/java/mission/user/application/UserController.java b/src/main/java/mission/user/application/UserController.java
index f32fbbc..119f8ab 100644
--- a/src/main/java/mission/user/application/UserController.java
+++ b/src/main/java/mission/user/application/UserController.java
@@ -1,7 +1,7 @@
 package mission.user.application;
 
 import lombok.RequiredArgsConstructor;
-import mission.user.implement.UserServiceImpl;
+import mission.user.business.UserService;
 import mission.user.dto.SignUpRequest;
 import mission.user.dto.SignUpResponse;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -14,10 +14,10 @@
 @RequiredArgsConstructor
 public class UserController {
 
-    private final UserServiceImpl userServiceImpl;
+    private final UserService userService;
 
     @PostMapping("/signup")
     public SignUpResponse signup(@RequestBody SignUpRequest request){
-        return userServiceImpl.signup(request);
+        return userService.signup(request);
     }
 }
diff --git a/src/main/java/mission/user/business/UserService.java b/src/main/java/mission/user/business/UserService.java
index 12d451b..b831a18 100644
--- a/src/main/java/mission/user/business/UserService.java
+++ b/src/main/java/mission/user/business/UserService.java
@@ -1,8 +1,33 @@
 package mission.user.business;
 
+import jakarta.transaction.Transactional;
+import lombok.RequiredArgsConstructor;
+import mission.user.domain.User;
 import mission.user.dto.SignUpRequest;
 import mission.user.dto.SignUpResponse;
+import mission.user.repository.UserRepository;
+import org.springframework.security.crypto.bcrypt.BCrypt;
+import org.springframework.stereotype.Service;
 
-public interface UserService {
-    SignUpResponse signup(SignUpRequest signUpRequest);
+@Service
+@RequiredArgsConstructor
+public class UserService {
+    private final UserRepository userRepository;
+
+    @Transactional
+    public SignUpResponse signup(SignUpRequest signUpRequest) {
+        if(userRepository.existsByEmail(signUpRequest.email())){
+            throw new IllegalArgumentException("email already in use");
+        }
+
+        String hashedPassword = BCrypt.hashpw(signUpRequest.password(), BCrypt.gensalt());
+        User saved = userRepository.save(
+                User.builder()
+                        .email(signUpRequest.email())
+                        .passwordHash(hashedPassword)
+                        .username(signUpRequest.username())
+                        .build()
+        );
+        return new SignUpResponse(saved.getEmail(), saved.getUsername());
+    }
 }
diff --git a/src/main/java/mission/user/implement/UserServiceImpl.java b/src/main/java/mission/user/implement/UserServiceImpl.java
deleted file mode 100644
index b69e774..0000000
--- a/src/main/java/mission/user/implement/UserServiceImpl.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package mission.user.implement;
-
-import jakarta.transaction.Transactional;
-import lombok.RequiredArgsConstructor;
-import mission.user.domain.User;
-import mission.user.dto.SignUpRequest;
-import mission.user.dto.SignUpResponse;
-import mission.user.repository.UserRepository;
-import mission.user.business.UserService;
-import org.springframework.security.crypto.bcrypt.BCrypt;
-import org.springframework.stereotype.Service;
-
-@Service
-@RequiredArgsConstructor
-public class UserServiceImpl implements UserService {
-    private final UserRepository userRepository;
-
-    @Override
-    @Transactional
-    public SignUpResponse signup(SignUpRequest signUpRequest) {
-        if(userRepository.existsByEmail(signUpRequest.email())){
-            throw new IllegalArgumentException("email already in use");
-        }
-
-        String hashedPassword = BCrypt.hashpw(signUpRequest.password(), BCrypt.gensalt());
-        User saved = userRepository.save(
-                User.builder()
-                        .email(signUpRequest.email())
-                        .passwordHash(hashedPassword)
-                        .username(signUpRequest.username())
-                        .build()
-        );
-        return new SignUpResponse(saved.getEmail(), saved.getUsername());
-    }
-}

From b327878ad5237b9862c502b23b00733528015c99 Mon Sep 17 00:00:00 2001
From: Shin-Yun-Cheol <yptlsdbscjf@naver.com>
Date: Tue, 30 Sep 2025 23:35:13 +0900
Subject: [PATCH 4/5] =?UTF-8?q?[#4];=20refactor=20:=20Service=EC=99=80=20I?=
 =?UTF-8?q?mplement=20=EA=B3=84=EC=B8=B5=20-=20service=EC=97=90=EC=84=9C?=
 =?UTF-8?q?=20Repository=EB=B0=94=EB=A1=9C=20=EC=A0=91=EA=B7=BC=20?=
 =?UTF-8?q?=EB=B3=B4=EB=8B=A4=20implement=EC=97=90=EC=84=9C=20repository?=
 =?UTF-8?q?=EB=A5=BC=20=EC=A0=91=EA=B7=BC=ED=95=B4=EC=84=9C=20service?=
 =?UTF-8?q?=EC=97=90=EC=84=9C=EB=8A=94=20=ED=9D=90=EB=A6=84=EC=9D=84=20?=
 =?UTF-8?q?=EB=B3=BC=20=EC=88=98=20=EC=9E=88=EA=B2=8C=20=EC=88=98=EC=A0=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../mission/post/business/PostService.java    | 38 ++++++++-----------
 .../mission/post/implement/PostReader.java    | 18 +++++++++
 .../mission/post/implement/PostWriter.java    | 16 ++++++++
 .../mission/user/implement/AuthVerifier.java  | 18 +++++++++
 .../mission/user/implement/UserReader.java    | 17 +++++++++
 5 files changed, 85 insertions(+), 22 deletions(-)
 create mode 100644 src/main/java/mission/post/implement/PostReader.java
 create mode 100644 src/main/java/mission/post/implement/PostWriter.java
 create mode 100644 src/main/java/mission/user/implement/AuthVerifier.java
 create mode 100644 src/main/java/mission/user/implement/UserReader.java

diff --git a/src/main/java/mission/post/business/PostService.java b/src/main/java/mission/post/business/PostService.java
index f077815..d3b649d 100644
--- a/src/main/java/mission/post/business/PostService.java
+++ b/src/main/java/mission/post/business/PostService.java
@@ -3,30 +3,30 @@
 import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
 import mission.post.domain.Post;
-import mission.post.repository.PostRepository;
+import mission.post.implement.PostReader;
+import mission.post.implement.PostWriter;
 import mission.post.dto.CreatePostRequest;
 import mission.post.dto.PostCreateResponse;
 import mission.post.dto.UpdatePostRequest;
 import mission.user.domain.User;
-import mission.user.repository.UserRepository;
-import org.springframework.security.crypto.bcrypt.BCrypt;
+import mission.user.implement.AuthVerifier;
+import mission.user.implement.UserReader;
 import org.springframework.stereotype.Service;
 
 @Service
 @RequiredArgsConstructor
 public class PostService {
-    private final PostRepository postRepository;
-    private final UserRepository userRepository;
-
+    private final PostReader postReader;
+    private final PostWriter postWriter;
+    private final UserReader userReader;
+    private final AuthVerifier authVerifier;
 
     @Transactional
     public PostCreateResponse create(CreatePostRequest createPostRequest) {
-        User author = userRepository.findByEmail(createPostRequest.email())
-                .orElseThrow(()->new IllegalArgumentException("email or password not found"));
-        if (!BCrypt.checkpw(createPostRequest.password(), author.getPasswordHash()))
-            throw new IllegalArgumentException("email or password does not match");
+        User author = userReader.getByEmail(createPostRequest.email());
+        authVerifier.verifyUserEmailAndPassword(author, createPostRequest.email(), createPostRequest.password());
 
-        Post saved = postRepository.save(
+        Post saved = postWriter.save(
                 Post.builder()
                         .title(createPostRequest.title())
                         .content(createPostRequest.content())
@@ -39,12 +39,9 @@ public PostCreateResponse create(CreatePostRequest createPostRequest) {
 
     @Transactional
     public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
-        Post post = postRepository.findById(id)
-                .orElseThrow(()->new IllegalArgumentException("post not found"));
+        Post post = postReader.getById(id);
 
-        if(!post.getAuthor().getEmail().equals(updatePostRequest.email()) || !BCrypt.checkpw(updatePostRequest.password(), post.getAuthor().getPasswordHash())){
-            throw new IllegalArgumentException("email or password does not match");
-        }
+        authVerifier.verifyUserEmailAndPassword(post.getAuthor(), updatePostRequest.email(), updatePostRequest.password());
 
         post.edit(updatePostRequest.title(), updatePostRequest.content());
 
@@ -57,13 +54,10 @@ public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
     }
     @Transactional
     public void delete(Long id, String email, String password){
-        Post post = postRepository.findById(id)
-                .orElseThrow(()->new IllegalArgumentException("post not found"));
+        Post post = postReader.getById(id);
 
-        if(!post.getAuthor().getEmail().equals(email) || !BCrypt.checkpw(password, post.getAuthor().getPasswordHash())){
-            throw new IllegalArgumentException("email or password does not match");
-        }
+        authVerifier.verifyUserEmailAndPassword(post.getAuthor(), email, password);
 
-        postRepository.delete(post);
+        postWriter.delete(post);
     }
 }
diff --git a/src/main/java/mission/post/implement/PostReader.java b/src/main/java/mission/post/implement/PostReader.java
new file mode 100644
index 0000000..f79e221
--- /dev/null
+++ b/src/main/java/mission/post/implement/PostReader.java
@@ -0,0 +1,18 @@
+package mission.post.implement;
+
+
+import lombok.RequiredArgsConstructor;
+import mission.post.domain.Post;
+import mission.post.repository.PostRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class PostReader {
+    private final PostRepository postRepository;
+
+    public Post getById(Long id) {
+        return postRepository.findById(id)
+                .orElseThrow(()->new IllegalArgumentException("post not found"));
+    }
+}
diff --git a/src/main/java/mission/post/implement/PostWriter.java b/src/main/java/mission/post/implement/PostWriter.java
new file mode 100644
index 0000000..6646ce7
--- /dev/null
+++ b/src/main/java/mission/post/implement/PostWriter.java
@@ -0,0 +1,16 @@
+package mission.post.implement;
+
+import lombok.RequiredArgsConstructor;
+import mission.post.domain.Post;
+import mission.post.repository.PostRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class PostWriter {
+    private final PostRepository postRepository;
+
+    public Post save(Post post){return postRepository.save(post);}
+    public void delete(Post post){postRepository.delete(post);}
+
+}
diff --git a/src/main/java/mission/user/implement/AuthVerifier.java b/src/main/java/mission/user/implement/AuthVerifier.java
new file mode 100644
index 0000000..74d21da
--- /dev/null
+++ b/src/main/java/mission/user/implement/AuthVerifier.java
@@ -0,0 +1,18 @@
+package mission.user.implement;
+
+import mission.user.domain.User;
+import org.springframework.security.crypto.bcrypt.BCrypt;
+import org.springframework.stereotype.Component;
+
+@Component
+public class AuthVerifier {
+    public void verifyUserEmailAndPassword(User user, String email, String password){
+        if (user == null || email == null || password == null) {
+            throw new IllegalArgumentException("email or password not found");
+        }
+        boolean ok = user.getEmail().equals(email) && BCrypt.checkpw(password, user.getPasswordHash());
+        if (!ok) {
+            throw new IllegalArgumentException("email or password does not match");
+        }
+    }
+}
diff --git a/src/main/java/mission/user/implement/UserReader.java b/src/main/java/mission/user/implement/UserReader.java
new file mode 100644
index 0000000..31e4fb0
--- /dev/null
+++ b/src/main/java/mission/user/implement/UserReader.java
@@ -0,0 +1,17 @@
+package mission.user.implement;
+
+import lombok.RequiredArgsConstructor;
+import mission.user.domain.User;
+import mission.user.repository.UserRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class UserReader {
+    private final UserRepository userRepository;
+
+    public User getByEmail(String email){
+        return userRepository.findByEmail(email)
+                .orElseThrow(()->new IllegalArgumentException("email not found"));
+    }
+}

From db2688ed219dd135e0602ef196e2783e36c4c653 Mon Sep 17 00:00:00 2001
From: Shin-Yun-Cheol <yptlsdbscjf@naver.com>
Date: Thu, 2 Oct 2025 00:23:24 +0900
Subject: [PATCH 5/5] =?UTF-8?q?[#5];=20feat=20:=20dto,=20command,=20result?=
 =?UTF-8?q?=20-=20dto=EB=8A=94=20controller=EC=97=90=EC=84=9C,=20command?=
 =?UTF-8?q?=EC=99=80=20result=EB=8A=94=20service=EC=97=90=EC=84=9C=20?=
 =?UTF-8?q?=EC=82=AC=EC=9A=A9=ED=95=A0=20=EC=88=98=20=EC=9E=88=EB=8F=84?=
 =?UTF-8?q?=EB=A1=9D=20=ED=95=98=EC=97=AC=20=EA=B0=81=EC=9E=90=20=EB=8B=A4?=
 =?UTF-8?q?=EB=A5=B8=20=EA=B1=B8=20=EC=B0=B8=EC=A1=B0=ED=95=A0=20=EC=88=98?=
 =?UTF-8?q?=20=EC=9E=88=EB=8F=84=EB=A1=9D=20=EC=88=98=EC=A0=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../post/application/PostController.java      | 21 ++++++++-----
 .../dto/CreatePostRequest.java                |  2 +-
 .../dto/PostCreateResponse.java               |  2 +-
 .../dto/UpdatePostRequest.java                |  2 +-
 .../mission/post/business/PostService.java    | 30 +++++++++----------
 .../business/command/CreatePostCommand.java   | 13 ++++++++
 .../business/command/UpdatePostCommand.java   | 15 ++++++++++
 .../post/business/result/PostResult.java      |  9 ++++++
 .../user/application/UserController.java      | 12 +++++---
 .../{ => application}/dto/SignUpRequest.java  |  2 +-
 .../{ => application}/dto/SignUpResponse.java |  2 +-
 .../mission/user/business/UserService.java    | 16 +++++-----
 .../user/business/command/SignUpCommand.java  | 13 ++++++++
 .../user/business/result/SignUpResult.java    |  6 ++++
 14 files changed, 105 insertions(+), 40 deletions(-)
 rename src/main/java/mission/post/{ => application}/dto/CreatePostRequest.java (83%)
 rename src/main/java/mission/post/{ => application}/dto/PostCreateResponse.java (77%)
 rename src/main/java/mission/post/{ => application}/dto/UpdatePostRequest.java (84%)
 create mode 100644 src/main/java/mission/post/business/command/CreatePostCommand.java
 create mode 100644 src/main/java/mission/post/business/command/UpdatePostCommand.java
 create mode 100644 src/main/java/mission/post/business/result/PostResult.java
 rename src/main/java/mission/user/{ => application}/dto/SignUpRequest.java (67%)
 rename src/main/java/mission/user/{ => application}/dto/SignUpResponse.java (63%)
 create mode 100644 src/main/java/mission/user/business/command/SignUpCommand.java
 create mode 100644 src/main/java/mission/user/business/result/SignUpResult.java

diff --git a/src/main/java/mission/post/application/PostController.java b/src/main/java/mission/post/application/PostController.java
index 70ff11a..c29ff5b 100644
--- a/src/main/java/mission/post/application/PostController.java
+++ b/src/main/java/mission/post/application/PostController.java
@@ -3,9 +3,12 @@
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 import mission.post.business.PostService;
-import mission.post.dto.CreatePostRequest;
-import mission.post.dto.PostCreateResponse;
-import mission.post.dto.UpdatePostRequest;
+import mission.post.application.dto.CreatePostRequest;
+import mission.post.application.dto.PostCreateResponse;
+import mission.post.application.dto.UpdatePostRequest;
+import mission.post.business.command.CreatePostCommand;
+import mission.post.business.command.UpdatePostCommand;
+import mission.post.business.result.PostResult;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 
@@ -18,13 +21,17 @@ public class PostController {
     private final PostService postService;
 
     @PostMapping
-    public PostCreateResponse create(@RequestBody @Valid CreatePostRequest createPostRequest) {
-        return postService.create(createPostRequest);
+    public PostCreateResponse create(@RequestBody @Valid CreatePostRequest req) {
+        var cmd = new CreatePostCommand(req.email(), req.password(), req.title(), req.content());
+        PostResult result = postService.create(cmd);
+        return new PostCreateResponse(result.articleId(), result.email(), result.title(), result.content());
     }
 
     @PutMapping("/{id}")
-    public PostCreateResponse update(@PathVariable Long id, @RequestBody @Valid UpdatePostRequest updatePostRequest) {
-        return postService.update(id, updatePostRequest);
+    public PostCreateResponse update(@PathVariable Long id, @RequestBody @Valid UpdatePostRequest req) {
+        var cmd = new UpdatePostCommand(id, req.email(), req.password(), req.title(), req.content());
+        PostResult result = postService.update(cmd);
+        return new PostCreateResponse(result.articleId(), result.email(), result.title(), result.content());
     }
 
     @DeleteMapping("/{id}")
diff --git a/src/main/java/mission/post/dto/CreatePostRequest.java b/src/main/java/mission/post/application/dto/CreatePostRequest.java
similarity index 83%
rename from src/main/java/mission/post/dto/CreatePostRequest.java
rename to src/main/java/mission/post/application/dto/CreatePostRequest.java
index e1a1179..b29acf3 100644
--- a/src/main/java/mission/post/dto/CreatePostRequest.java
+++ b/src/main/java/mission/post/application/dto/CreatePostRequest.java
@@ -1,4 +1,4 @@
-package mission.post.dto;
+package mission.post.application.dto;
 
 import jakarta.validation.constraints.NotBlank;
 
diff --git a/src/main/java/mission/post/dto/PostCreateResponse.java b/src/main/java/mission/post/application/dto/PostCreateResponse.java
similarity index 77%
rename from src/main/java/mission/post/dto/PostCreateResponse.java
rename to src/main/java/mission/post/application/dto/PostCreateResponse.java
index edacb03..f5f7f1f 100644
--- a/src/main/java/mission/post/dto/PostCreateResponse.java
+++ b/src/main/java/mission/post/application/dto/PostCreateResponse.java
@@ -1,4 +1,4 @@
-package mission.post.dto;
+package mission.post.application.dto;
 
 public record PostCreateResponse(
         Long articleId,
diff --git a/src/main/java/mission/post/dto/UpdatePostRequest.java b/src/main/java/mission/post/application/dto/UpdatePostRequest.java
similarity index 84%
rename from src/main/java/mission/post/dto/UpdatePostRequest.java
rename to src/main/java/mission/post/application/dto/UpdatePostRequest.java
index b5d8091..fc44e8c 100644
--- a/src/main/java/mission/post/dto/UpdatePostRequest.java
+++ b/src/main/java/mission/post/application/dto/UpdatePostRequest.java
@@ -1,4 +1,4 @@
-package mission.post.dto;
+package mission.post.application.dto;
 
 import jakarta.validation.constraints.NotBlank;
 
diff --git a/src/main/java/mission/post/business/PostService.java b/src/main/java/mission/post/business/PostService.java
index d3b649d..95255d3 100644
--- a/src/main/java/mission/post/business/PostService.java
+++ b/src/main/java/mission/post/business/PostService.java
@@ -2,12 +2,12 @@
 
 import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
+import mission.post.business.command.CreatePostCommand;
+import mission.post.business.command.UpdatePostCommand;
+import mission.post.business.result.PostResult;
 import mission.post.domain.Post;
 import mission.post.implement.PostReader;
 import mission.post.implement.PostWriter;
-import mission.post.dto.CreatePostRequest;
-import mission.post.dto.PostCreateResponse;
-import mission.post.dto.UpdatePostRequest;
 import mission.user.domain.User;
 import mission.user.implement.AuthVerifier;
 import mission.user.implement.UserReader;
@@ -22,30 +22,28 @@ public class PostService {
     private final AuthVerifier authVerifier;
 
     @Transactional
-    public PostCreateResponse create(CreatePostRequest createPostRequest) {
-        User author = userReader.getByEmail(createPostRequest.email());
-        authVerifier.verifyUserEmailAndPassword(author, createPostRequest.email(), createPostRequest.password());
+    public PostResult create(CreatePostCommand createPostCommand) {
+        User author = userReader.getByEmail(createPostCommand.email());
+        authVerifier.verifyUserEmailAndPassword(author, createPostCommand.email(), createPostCommand.password());
 
         Post saved = postWriter.save(
                 Post.builder()
-                        .title(createPostRequest.title())
-                        .content(createPostRequest.content())
+                        .title(createPostCommand.title())
+                        .content(createPostCommand.content())
                         .author(author)
                         .build()
         );
 
-        return new PostCreateResponse(saved.getId(), author.getEmail(), saved.getTitle(), saved.getContent());
+        return new PostResult(saved.getId(), saved.getAuthor().getEmail(), saved.getTitle(), saved.getContent());
     }
 
     @Transactional
-    public PostCreateResponse update(Long id, UpdatePostRequest updatePostRequest){
-        Post post = postReader.getById(id);
-
-        authVerifier.verifyUserEmailAndPassword(post.getAuthor(), updatePostRequest.email(), updatePostRequest.password());
-
-        post.edit(updatePostRequest.title(), updatePostRequest.content());
+    public PostResult update(UpdatePostCommand updatePostCommand) {
+        Post post = postReader.getById(updatePostCommand.id());
+        authVerifier.verifyUserEmailAndPassword(post.getAuthor(), updatePostCommand.email(), updatePostCommand.password());
+        post.edit(updatePostCommand.title(), updatePostCommand.content());
 
-        return new PostCreateResponse(
+        return new PostResult(
                 post.getId(),
                 post.getAuthor().getEmail(),
                 post.getTitle(),
diff --git a/src/main/java/mission/post/business/command/CreatePostCommand.java b/src/main/java/mission/post/business/command/CreatePostCommand.java
new file mode 100644
index 0000000..e557af1
--- /dev/null
+++ b/src/main/java/mission/post/business/command/CreatePostCommand.java
@@ -0,0 +1,13 @@
+package mission.post.business.command;
+
+public record CreatePostCommand (
+    String email,
+    String password,
+    String title,
+    String content
+) {
+    public CreatePostCommand {
+        if (title == null || title.isBlank()) throw new IllegalArgumentException("title is null or empty");
+        if (content == null || content.isBlank()) throw new IllegalArgumentException("content is null or empty");
+    }
+}
diff --git a/src/main/java/mission/post/business/command/UpdatePostCommand.java b/src/main/java/mission/post/business/command/UpdatePostCommand.java
new file mode 100644
index 0000000..46aeba6
--- /dev/null
+++ b/src/main/java/mission/post/business/command/UpdatePostCommand.java
@@ -0,0 +1,15 @@
+package mission.post.business.command;
+
+public record UpdatePostCommand(
+        Long id,
+        String email,
+        String password,
+        String title,
+        String content
+) {
+    public UpdatePostCommand{
+        if(id==null) throw new IllegalArgumentException("id is null");
+        if(title==null || title.isBlank()) throw new IllegalArgumentException("title is null or empty");
+        if(content==null || content.isBlank()) throw new IllegalArgumentException("content is null or empty");
+    }
+}
diff --git a/src/main/java/mission/post/business/result/PostResult.java b/src/main/java/mission/post/business/result/PostResult.java
new file mode 100644
index 0000000..0c13b82
--- /dev/null
+++ b/src/main/java/mission/post/business/result/PostResult.java
@@ -0,0 +1,9 @@
+package mission.post.business.result;
+
+public record PostResult(
+        Long articleId,
+        String email,
+        String title,
+        String content
+) {
+}
diff --git a/src/main/java/mission/user/application/UserController.java b/src/main/java/mission/user/application/UserController.java
index 119f8ab..e1aaf55 100644
--- a/src/main/java/mission/user/application/UserController.java
+++ b/src/main/java/mission/user/application/UserController.java
@@ -2,8 +2,10 @@
 
 import lombok.RequiredArgsConstructor;
 import mission.user.business.UserService;
-import mission.user.dto.SignUpRequest;
-import mission.user.dto.SignUpResponse;
+import mission.user.application.dto.SignUpRequest;
+import mission.user.application.dto.SignUpResponse;
+import mission.user.business.command.SignUpCommand;
+import mission.user.business.result.SignUpResult;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -17,7 +19,9 @@ public class UserController {
     private final UserService userService;
 
     @PostMapping("/signup")
-    public SignUpResponse signup(@RequestBody SignUpRequest request){
-        return userService.signup(request);
+    public SignUpResponse signup(@RequestBody SignUpRequest req) {
+        var cmd = new SignUpCommand(req.email(), req.password(), req.username());
+        SignUpResult result = userService.signup(cmd);
+        return new SignUpResponse(result.email(), result.username());
     }
 }
diff --git a/src/main/java/mission/user/dto/SignUpRequest.java b/src/main/java/mission/user/application/dto/SignUpRequest.java
similarity index 67%
rename from src/main/java/mission/user/dto/SignUpRequest.java
rename to src/main/java/mission/user/application/dto/SignUpRequest.java
index 5712e94..ae486d4 100644
--- a/src/main/java/mission/user/dto/SignUpRequest.java
+++ b/src/main/java/mission/user/application/dto/SignUpRequest.java
@@ -1,3 +1,3 @@
-package mission.user.dto;
+package mission.user.application.dto;
 
 public record SignUpRequest(String email, String password, String username) {}
diff --git a/src/main/java/mission/user/dto/SignUpResponse.java b/src/main/java/mission/user/application/dto/SignUpResponse.java
similarity index 63%
rename from src/main/java/mission/user/dto/SignUpResponse.java
rename to src/main/java/mission/user/application/dto/SignUpResponse.java
index c6b4b8f..181a612 100644
--- a/src/main/java/mission/user/dto/SignUpResponse.java
+++ b/src/main/java/mission/user/application/dto/SignUpResponse.java
@@ -1,4 +1,4 @@
-package mission.user.dto;
+package mission.user.application.dto;
 
 
 public record SignUpResponse(String email, String username) {}
diff --git a/src/main/java/mission/user/business/UserService.java b/src/main/java/mission/user/business/UserService.java
index b831a18..4da116f 100644
--- a/src/main/java/mission/user/business/UserService.java
+++ b/src/main/java/mission/user/business/UserService.java
@@ -2,9 +2,9 @@
 
 import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
+import mission.user.business.command.SignUpCommand;
+import mission.user.business.result.SignUpResult;
 import mission.user.domain.User;
-import mission.user.dto.SignUpRequest;
-import mission.user.dto.SignUpResponse;
 import mission.user.repository.UserRepository;
 import org.springframework.security.crypto.bcrypt.BCrypt;
 import org.springframework.stereotype.Service;
@@ -15,19 +15,19 @@ public class UserService {
     private final UserRepository userRepository;
 
     @Transactional
-    public SignUpResponse signup(SignUpRequest signUpRequest) {
-        if(userRepository.existsByEmail(signUpRequest.email())){
+    public SignUpResult signup(SignUpCommand signUpCommand) {
+        if(userRepository.existsByEmail(signUpCommand.email())){
             throw new IllegalArgumentException("email already in use");
         }
 
-        String hashedPassword = BCrypt.hashpw(signUpRequest.password(), BCrypt.gensalt());
+        String hashedPassword = BCrypt.hashpw(signUpCommand.password(), BCrypt.gensalt());
         User saved = userRepository.save(
                 User.builder()
-                        .email(signUpRequest.email())
+                        .email(signUpCommand.email())
                         .passwordHash(hashedPassword)
-                        .username(signUpRequest.username())
+                        .username(signUpCommand.username())
                         .build()
         );
-        return new SignUpResponse(saved.getEmail(), saved.getUsername());
+        return new SignUpResult(saved.getEmail(), saved.getUsername());
     }
 }
diff --git a/src/main/java/mission/user/business/command/SignUpCommand.java b/src/main/java/mission/user/business/command/SignUpCommand.java
new file mode 100644
index 0000000..52c82a2
--- /dev/null
+++ b/src/main/java/mission/user/business/command/SignUpCommand.java
@@ -0,0 +1,13 @@
+package mission.user.business.command;
+
+public record SignUpCommand(
+        String email,
+        String password,
+        String username
+) {
+    public SignUpCommand {
+        if(email==null || email.isBlank()) throw new IllegalArgumentException("email is null or empty");
+        if(password==null || password.isBlank()) throw new IllegalArgumentException("password is null or empty");
+        if(username==null || username.isBlank()) throw new IllegalArgumentException("username is null or empty");
+    }
+}
diff --git a/src/main/java/mission/user/business/result/SignUpResult.java b/src/main/java/mission/user/business/result/SignUpResult.java
new file mode 100644
index 0000000..dad67d3
--- /dev/null
+++ b/src/main/java/mission/user/business/result/SignUpResult.java
@@ -0,0 +1,6 @@
+package mission.user.business.result;
+
+public record SignUpResult(
+        String email,
+        String username
+) {}