Handle duplicate Google social users

Author: jjoonleo

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

@@ -18,8 +18,8 @@
 import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 
 @Slf4j
@@ -48,10 +48,14 @@ public Authentication attemptAuthentication(HttpServletRequest request, HttpServ
 
             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);
+                List<User> existingUsers = userRepository.findAllBySocialTypeAndSocialIdOrderByIdDesc(SocialType.GOOGLE, googleUserId);
+
+                if (!existingUsers.isEmpty()) {
+                    if (existingUsers.size() > 1) {
+                        log.warn("동일한 Google socialId를 가진 유저가 {}명 존재합니다. 최신 userId={} 계정으로 로그인합니다.",
+                                existingUsers.size(), existingUsers.get(0).getId());
+                    }
+                    return googleLoginService.handleLogin(oAuthGoogleRequestDto, existingUsers.get(0), response);
                 } else {
                     OAuthGoogleUserDto oAuthGoogleUserDto = new OAuthGoogleUserDto(googleUserId, (String) googlePayload.get("name"), (String) googlePayload.get("picture"), googlePayload.getEmail());
                     return googleLoginService.handleRegister(oAuthGoogleRequestDto, oAuthGoogleUserDto, response);

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

@@ -6,6 +6,7 @@
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.stereotype.Repository;
 
+import java.util.List;
 import java.util.Optional;
 
 @Repository
@@ -21,8 +22,10 @@ public interface UserRepository extends JpaRepository<User, Long> {
     // 추가정보 입력받을때 사용
     Optional<User> findBySocialTypeAndSocialId(SocialType socialType, String socialId);
 
+    List<User> findAllBySocialTypeAndSocialIdOrderByIdDesc(SocialType socialType, String socialId);
+
     @Query("SELECT u.spareTime FROM User u WHERE u.id = :id")
     Integer findSpareTimeById(Long id);
 
     Optional<Object> findByAccessToken(String token);
-}
+}