[Refactor] OAuth ID 타입 Long → String으로 변경

Author: soonge2

src/main/java/com/moa/moa_server/domain/auth/entity/OAuth.java

@@ -18,7 +18,7 @@ public class OAuth {
 
     @Id
     @Column(length = 100, nullable = false)
-    private Long id; // 소셜 사용자 ID
+    private String id; // 소셜 사용자 ID
 
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "user_id", nullable = false)

src/main/java/com/moa/moa_server/domain/auth/handler/AuthErrorCode.java

@@ -14,7 +14,8 @@ public enum AuthErrorCode implements BaseErrorCode {
     KAKAO_TOKEN_FAILED(HttpStatus.UNAUTHORIZED),
     KAKAO_USERINFO_FAILED(HttpStatus.UNAUTHORIZED),
     OAUTH_NOT_FOUND(HttpStatus.NOT_FOUND),
-    INVALID_REDIRECT_URI(HttpStatus.BAD_REQUEST),;
+    INVALID_REDIRECT_URI(HttpStatus.BAD_REQUEST),
+    INVALID_KAKAO_ID(HttpStatus.INTERNAL_SERVER_ERROR),;
 
     private final HttpStatus status;
 

src/main/java/com/moa/moa_server/domain/auth/repository/OAuthRepository.java

@@ -9,7 +9,7 @@
 
 public interface OAuthRepository extends JpaRepository<OAuth, Long> {
 
-    Optional<OAuth> findById(@NonNull Long id);
+    Optional<OAuth> findById(@NonNull String id);
     void deleteByUserId(Long userId);
     Optional<OAuth> findByUser(User user);
 }

src/main/java/com/moa/moa_server/domain/auth/service/strategy/KakaoOAuthLoginStrategy.java

@@ -65,7 +65,7 @@ public LoginResult login(String code, String redirectUri) {
         String kakaoAccessToken = getAccessToken(code, redirectUri);
 
         // 카카오 액세스 토큰으로 사용자 정보 요청
-        Long kakaoId = getUserInfo(kakaoAccessToken);
+        String kakaoId = getUserInfo(kakaoAccessToken);
 
         // 사용자 정보 DB 조회
         Optional<OAuth> oAuthOptional = oAuthRepository.findById(kakaoId);
@@ -116,7 +116,7 @@ private String getAccessToken(String code, String redirectUri) {
         }
     }
 
-    private Long getUserInfo(String accessToken) {
+    private String getUserInfo(String accessToken) {
 
         HttpHeaders headers = new HttpHeaders();
         headers.setBearerAuth(accessToken);
@@ -126,7 +126,8 @@ private Long getUserInfo(String accessToken) {
 
         try {
             ResponseEntity<Map> response = restTemplate.postForEntity(kakaoUserInfoUri, request, Map.class);
-            return (Long) response.getBody().get("id");
+            Object kakaoId = response.getBody().get("id");
+            return String.valueOf(kakaoId);
         } catch (Exception e) {
             throw new AuthException(AuthErrorCode.KAKAO_USERINFO_FAILED);
         }

src/main/java/com/moa/moa_server/domain/user/service/UserService.java

@@ -158,11 +158,16 @@ public void deleteUser(Long userId) {
         voteRepository.softDeleteAllByUser(user);
 
         // 4. 카카오 연동 해제
-        Long kakaoUserId = oauthRepository.findByUser(user)
+        String kakaoUserId = oauthRepository.findByUser(user)
                 .filter(oauth -> oauth.getProviderCode() == OAuth.ProviderCode.KAKAO)
                 .map(OAuth::getId)
                 .orElseThrow(() -> new AuthException(AuthErrorCode.OAUTH_NOT_FOUND));
-        authService.unlinkKakaoAccount(kakaoUserId);
+        try {
+            Long kakaoUserIdLong = Long.parseLong(kakaoUserId);
+            authService.unlinkKakaoAccount(kakaoUserIdLong);
+        } catch (NumberFormatException e) {
+            throw new AuthException(AuthErrorCode.INVALID_KAKAO_ID);
+        }
 
         // 5. 토큰, OAuth 삭제 (hard delete)
         tokenRepository.deleteByUserId(userId);