[codex] Add account deletion feedback

docs/account-deletion-api.md

@@ -0,0 +1,180 @@
+# Account Deletion API
+
+Frontend integration guide for deleting an OnTime account with optional withdrawal feedback.
+
+## Summary
+
+Account deletion hard-deletes the user from OnTime. The request can optionally include feedback. If feedback is provided, the backend stores it separately from the `User` table so it remains available after the account is deleted.
+
+For Google and Apple social accounts, the backend first tries to revoke the social login token, then deletes the local OnTime account.
+
+## Authentication
+
+All endpoints require the current OnTime access token.
+
+```http
+Authorization: Bearer {accessToken}
+Content-Type: application/json
+```
+
+## Request Body
+
+The request body is optional for every deletion endpoint.
+
+```json
+{
+  "feedbackId": "d784cde3-9ff9-4054-872a-500bbcc2198a",
+  "message": "I do not use the app anymore."
+}
+```
+
+Fields:
+
+| Field | Type | Required | Notes |
+| --- | --- | --- | --- |
+| `feedbackId` | UUID string | No | Client-generated ID. If omitted, the backend generates one. |
+| `message` | string | No | If missing, blank, or only whitespace, feedback is not saved and deletion still proceeds. |
+
+## General Account Deletion
+
+Use this endpoint for normal OnTime account deletion.
+
+```http
+DELETE /users/me/delete
+```
+
+Example without feedback:
+
+```http
+DELETE /users/me/delete
+Authorization: Bearer {accessToken}
+Content-Type: application/json
+
+{}
+```
+
+Example with feedback:
+
+```http
+DELETE /users/me/delete
+Authorization: Bearer {accessToken}
+Content-Type: application/json
+
+{
+  "feedbackId": "d784cde3-9ff9-4054-872a-500bbcc2198a",
+  "message": "The notifications were not useful for me."
+}
+```
+
+Success response:
+
+```json
+{
+  "status": "success",
+  "code": "200",
+  "message": "계정이 성공적으로 삭제되었습니다!",
+  "data": null
+}
+```
+
+## Google Account Deletion
+
+Use this endpoint when the current account is linked through Google login.
+
+```http
+DELETE /oauth2/google/me
+```
+
+Example:
+
+```http
+DELETE /oauth2/google/me
+Authorization: Bearer {accessToken}
+Content-Type: application/json
+
+{
+  "message": "I am switching to another calendar app."
+}
+```
+
+Success response:
+
+```text
+구글 로그인 회원탈퇴 성공
+```
+
+Behavior:
+
+- Revokes the stored Google OAuth token for OnTime.
+- Deletes the local OnTime account.
+- Saves optional feedback if `message` is nonblank.
+- Does not delete the user's actual Google account.
+
+Expected frontend result after successful revoke:
+
+- If the user signs up or logs in with the same Google account again, Google may show an "OnTime에 다시 로그인하는 중입니다" confirmation screen.
+- The Google account can still be preselected because the user is still signed in to Google on the device/browser.
+
+Important caveat:
+
+- The Google unlink only works if the backend has a valid Google refresh/access token saved in `socialLoginToken`.
+- If the client never provided a real Google refresh token, Google revoke may fail and the endpoint may return an error before local deletion.
+
+## Apple Account Deletion
+
+Use this endpoint when the current account is linked through Apple login.
+
+```http
+DELETE /oauth2/apple/me
+```
+
+Example:
+
+```http
+DELETE /oauth2/apple/me
+Authorization: Bearer {accessToken}
+Content-Type: application/json
+
+{
+  "feedbackId": "85fc54e0-e6c7-4c7e-9312-7784a52bf120",
+  "message": "I want to restart with a fresh account."
+}
+```
+
+Success response:
+
+```text
+애플 로그인 회원탈퇴 성공
+```
+
+Behavior:
+
+- Revokes the stored Apple OAuth token for OnTime.
+- Deletes the local OnTime account.
+- Saves optional feedback if `message` is nonblank.
+- Does not delete the user's Apple ID.
+
+## What Gets Stored For Feedback
+
+When feedback is provided, the backend stores:
+
+| Stored Field | Notes |
+| --- | --- |
+| `feedbackId` | Client-provided UUID or backend-generated UUID |
+| `deletedUserId` | Previous OnTime user ID |
+| `socialType` | `GOOGLE`, `APPLE`, or null for non-social accounts |
+| `emailHash` | SHA-256 hash of the normalized email, not plaintext email |
+| `message` | User feedback text |
+| `createdAt` | Server timestamp |
+
+Feedback is not linked by foreign key to the deleted user.
+
+## Frontend Recommendations
+
+- Treat feedback as optional. Do not block deletion if the user skips it.
+- Generate a UUID for `feedbackId` if convenient, but it is safe to omit.
+- Use `/oauth2/google/me` for Google-linked accounts if the product requirement is to unlink Google access.
+- Use `/oauth2/apple/me` for Apple-linked accounts if the product requirement is to unlink Apple access.
+- Use `/users/me/delete` for normal local deletion.
+- After a successful deletion response, clear local auth state and navigate to the logged-out screen.
+- Do not retry automatically on social revoke errors without showing the user, because the local account may not have been deleted.

ontime-back/src/main/java/devkor/ontime_back/controller/SocialAuthController.java

@@ -1,5 +1,6 @@
 package devkor.ontime_back.controller;
 
+import devkor.ontime_back.dto.FeedbackAddDto;
 import devkor.ontime_back.dto.OAuthAppleRequestDto;
 import devkor.ontime_back.dto.OAuthGoogleUserDto;
 import devkor.ontime_back.dto.OAuthKakaoUserDto;
@@ -112,24 +113,24 @@ public String appleRegisterOrLogin(@RequestBody OAuthAppleRequestDto appleLoginR
             summary = "애플 소셜 로그인 회원탈퇴"
     )
     @DeleteMapping("/apple/me")
-    public String appleDeleteUser(HttpServletRequest request, HttpServletResponse response) throws Exception {
+    public String appleDeleteUser(HttpServletRequest request, HttpServletResponse response, @RequestBody(required = false) FeedbackAddDto feedbackAddDto) throws Exception {
         Long userId = userAuthService.getUserIdFromToken(request);
         log.info("userId: {}", userId);
         appleLoginService.revokeToken(userId);
-        userAuthService.deleteUser(userId);
+        userAuthService.deleteUser(userId, feedbackAddDto);
         return "애플 로그인 회원탈퇴 성공";
     }
 
     @Operation(
             summary = "구글 소셜 로그인 회원탈퇴"
     )
     @DeleteMapping("/google/me")
-    public String googleDeleteUser(HttpServletRequest request, HttpServletResponse response) throws Exception {
+    public String googleDeleteUser(HttpServletRequest request, HttpServletResponse response, @RequestBody(required = false) FeedbackAddDto feedbackAddDto) throws Exception {
         Long userId = userAuthService.getUserIdFromToken(request);
         log.info("userId: {}", userId);
         googleLoginService.revokeToken(userId);
-        userAuthService.deleteUser(userId);
-        return "애플 로그인 회원탈퇴 성공";
+        userAuthService.deleteUser(userId, feedbackAddDto);
+        return "구글 로그인 회원탈퇴 성공";
     }
 
 

ontime-back/src/main/java/devkor/ontime_back/controller/UserAuthController.java

@@ -1,6 +1,7 @@
 package devkor.ontime_back.controller;
 
 import devkor.ontime_back.dto.ChangePasswordDto;
+import devkor.ontime_back.dto.FeedbackAddDto;
 import devkor.ontime_back.dto.UserInfoResponse;
 import devkor.ontime_back.dto.UserSignUpDto;
 import devkor.ontime_back.entity.User;
@@ -107,11 +108,11 @@ public ResponseEntity<ApiResponseForm<String>> changePassword(HttpServletRequest
     @Operation(
             summary = "계정 삭제 (User 데이터 하드 삭제)",
             requestBody = @io.swagger.v3.oas.annotations.parameters.RequestBody(
-                    description = "계정 삭제 요청 JSON 데이터는 없음. 헤더에 토큰만 있으면 됨",
+                    description = "계정 삭제 요청 JSON 데이터는 선택사항. 탈퇴 피드백을 남기려면 feedbackId, message를 전달",
                     content = @Content(
                             schema = @Schema(
                                     type = "object",
-                                    example = "{}"
+                                    example = "{\"feedbackId\": \"d784cde3-9ff9-4054-872a-500bbcc2198a\", \"message\": \"탈퇴 피드백입니다.\"}"
                             )
                     )
             )
@@ -126,9 +127,9 @@ public ResponseEntity<ApiResponseForm<String>> changePassword(HttpServletRequest
             @ApiResponse(responseCode = "4XX", description = "계정 삭제 실패", content = @Content(mediaType = "application/json", schema = @Schema(example = "실패 메세지(토큰 오류 제외 비즈니스 로직 오류는 없음)")))
     })
     @DeleteMapping("/users/me/delete")
-    public ResponseEntity<ApiResponseForm<?>> deleteUser(HttpServletRequest request) {
+    public ResponseEntity<ApiResponseForm<?>> deleteUser(HttpServletRequest request, @RequestBody(required = false) FeedbackAddDto feedbackAddDto) {
         Long userId = userAuthService.getUserIdFromToken(request);
-        userAuthService.deleteUser(userId);
+        userAuthService.deleteUser(userId, feedbackAddDto);
         String message = "계정이 성공적으로 삭제되었습니다!";
         return ResponseEntity.ok(ApiResponseForm.success(null, message));
     }

ontime-back/src/main/java/devkor/ontime_back/dto/FeedbackAddDto.java

@@ -1,12 +1,14 @@
 package devkor.ontime_back.dto;
 
-import lombok.Getter;
-import lombok.ToString;
+import lombok.*;
 
 import java.util.UUID;
 
 @ToString
 @Getter
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
 public class FeedbackAddDto {
     private UUID feedbackId;
     private String message;

ontime-back/src/main/java/devkor/ontime_back/entity/AccountDeletionFeedback.java

@@ -0,0 +1,32 @@
+package devkor.ontime_back.entity;
+
+import jakarta.persistence.*;
+import lombok.*;
+
+import java.time.LocalDateTime;
+import java.util.UUID;
+
+@Getter
+@Entity
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Builder
+public class AccountDeletionFeedback {
+
+    @Id
+    private UUID feedbackId;
+
+    private Long deletedUserId;
+
+    @Enumerated(EnumType.STRING)
+    private SocialType socialType;
+
+    @Column(length = 64)
+    private String emailHash;
+
+    @Lob
+    @Column(columnDefinition = "TEXT")
+    private String message;
+
+    private LocalDateTime createdAt;
+}

ontime-back/src/main/java/devkor/ontime_back/global/jwt/JwtAuthenticationFilter.java

@@ -107,15 +107,12 @@ public void checkAccessTokenAndAuthentication(HttpServletRequest request, HttpSe
                                                   FilterChain filterChain) throws ServletException, IOException {
         log.info("checkAccessTokenAndAuthentication() 호출");
         jwtTokenProvider.extractAccessToken(request)
-                .ifPresent(accessToken -> {
-                    jwtTokenProvider.extractEmail(accessToken)
-                            .ifPresent(email -> userRepository.findByEmail(email)
-                                    .ifPresent(this::saveAuthentication)
-                            );
-
-                    jwtTokenProvider.extractUserId(accessToken)
-                            .ifPresent(userId -> log.info("추출된 userId: {}", userId));
-                });
+                .ifPresent(accessToken -> jwtTokenProvider.extractUserId(accessToken)
+                        .ifPresent(userId -> {
+                            log.info("추출된 userId: {}", userId);
+                            userRepository.findById(userId)
+                                    .ifPresent(this::saveAuthentication);
+                        }));
 
         filterChain.doFilter(request, response);
     }
@@ -192,4 +189,4 @@ private void handleInvalidTokenException(HttpServletResponse response, InvalidTo
             response.getWriter().write(objectMapper.writeValueAsString(errorResponse));
         }
     }
-}
+}

ontime-back/src/main/java/devkor/ontime_back/global/jwt/JwtTokenProvider.java

@@ -71,6 +71,7 @@ public String createRefreshToken() {
         return JWT.create()
                 .withSubject(REFRESH_TOKEN_SUBJECT)
                 .withExpiresAt(new Date(now.getTime() + refreshTokenExpirationPeriod))
+                .withJWTId(UUID.randomUUID().toString())
                 .sign(Algorithm.HMAC512(secretKey));
     }
 
@@ -199,4 +200,4 @@ public String createExpiredAccessToken(String email) {
                 .sign(Algorithm.HMAC512(secretKey));
     }
 
-}
+}

ontime-back/src/main/java/devkor/ontime_back/global/oauth/google/GoogleLoginFilter.java

@@ -18,10 +18,14 @@
 import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
 
 import java.io.IOException;
+import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
 
 @Slf4j
 public class GoogleLoginFilter extends AbstractAuthenticationProcessingFilter {
+    private static final Map<String, Object> LOGIN_LOCKS = new ConcurrentHashMap<>();
+
     private final UserRepository userRepository;
     private final GoogleLoginService googleLoginService;
 
@@ -42,13 +46,16 @@ public Authentication attemptAuthentication(HttpServletRequest request, HttpServ
             GoogleIdToken.Payload googlePayload = googleLoginService.verifyIdentityToken(oAuthGoogleRequestDto.getIdToken());
             String googleUserId = googlePayload.getSubject();
 
-            Optional<User> existingUser = userRepository.findBySocialTypeAndSocialId(SocialType.GOOGLE, googleUserId);
+            Object loginLock = LOGIN_LOCKS.computeIfAbsent(googleUserId, key -> new Object());
+            synchronized (loginLock) {
+                Optional<User> existingUser = userRepository.findBySocialTypeAndSocialId(SocialType.GOOGLE, googleUserId);
 
-            if (existingUser.isPresent()) {
-                return googleLoginService.handleLogin(oAuthGoogleRequestDto, existingUser.get(), response);
-            } else {
-                OAuthGoogleUserDto oAuthGoogleUserDto = new OAuthGoogleUserDto(googleUserId, (String) googlePayload.get("name"), (String) googlePayload.get("picture"), googlePayload.getEmail());
-                return googleLoginService.handleRegister(oAuthGoogleRequestDto, oAuthGoogleUserDto, response);
+                if (existingUser.isPresent()) {
+                    return googleLoginService.handleLogin(oAuthGoogleRequestDto, existingUser.get(), response);
+                } else {
+                    OAuthGoogleUserDto oAuthGoogleUserDto = new OAuthGoogleUserDto(googleUserId, (String) googlePayload.get("name"), (String) googlePayload.get("picture"), googlePayload.getEmail());
+                    return googleLoginService.handleRegister(oAuthGoogleRequestDto, oAuthGoogleUserDto, response);
+                }
             }
 
         } catch (Exception e) {

ontime-back/src/main/java/devkor/ontime_back/repository/AccountDeletionFeedbackRepository.java

@@ -0,0 +1,11 @@
+package devkor.ontime_back.repository;
+
+import devkor.ontime_back.entity.AccountDeletionFeedback;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+import java.util.UUID;
+
+@Repository
+public interface AccountDeletionFeedbackRepository extends JpaRepository<AccountDeletionFeedback, UUID> {
+}