[improve/#285] JWT 필터에 캐싱 도입

src/main/java/com/techfork/domain/auth/service/AuthService.java

@@ -12,6 +12,7 @@
 import com.techfork.domain.user.repository.UserRepository;
 import com.techfork.global.exception.GeneralException;
 import com.techfork.global.security.auth.service.RefreshTokenService;
+import com.techfork.global.security.auth.service.UserAuthCacheService;
 import com.techfork.global.security.jwt.JwtDTO;
 import com.techfork.global.security.jwt.JwtProperties;
 import com.techfork.global.security.jwt.JwtUtil;
@@ -37,6 +38,7 @@ public class AuthService {
     private final JwtProperties jwtProperties;
     private final AuthConverter authConverter;
     private final KakaoOAuthService kakaoOAuthService;
+    private final UserAuthCacheService userAuthCacheService;
 
     @Value("${server.domain}")
     private String domain;
@@ -54,7 +56,9 @@ public TokenRefreshResponse refreshToken(String refreshToken, HttpServletRespons
         long expiration = jwtProperties.getRefreshTokenExpiration();
         saveAndSetRefreshToken(response, userId, newTokens.refreshToken(), expiration);
 
-        log.info("Token refreshed for userId: {}", userId);
+        userAuthCacheService.put(userId, user, jwtProperties.getAccessTokenExpiration());
+
+        log.info("Token refreshed");
 
         return TokenRefreshResponse.builder()
                 .accessToken(newTokens.accessToken())

src/main/java/com/techfork/domain/user/service/UserCommandService.java

@@ -7,6 +7,7 @@
 import com.techfork.domain.user.exception.UserErrorCode;
 import com.techfork.domain.user.repository.UserRepository;
 import com.techfork.global.exception.GeneralException;
+import com.techfork.global.security.auth.service.UserAuthCacheService;
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
@@ -21,6 +22,7 @@ public class UserCommandService {
 
     private final InterestCommandService interestCommandService;
     private final UserRepository userRepository;
+    private final UserAuthCacheService userAuthCacheService;
 
     public void completeOnboarding(Long userId, @Valid OnboardingRequest request) {
         User user = userRepository.findByIdWithInterestCategories(userId)
@@ -29,6 +31,8 @@ public void completeOnboarding(Long userId, @Valid OnboardingRequest request) {
         user.updateUser(request.nickname(), request.email(), request.description());
 
         interestCommandService.saveUserInterests(user, new SaveInterestRequest(request.interests()));
+
+        userAuthCacheService.evict(userId);
     }
 
     public void updateUserProfile(Long userId, UpdateUserProfileRequest request) {
@@ -52,7 +56,8 @@ public void withdrawUser(Long userId) {
         }
 
         user.withdraw();
+        userAuthCacheService.evict(userId);
 
-        log.info("User withdrawn - userId: {}, status changed to WITHDRAWN and personal data anonymized", userId);
+        log.info("User withdrawn - status changed to WITHDRAWN and personal data anonymized");
     }
 }

src/main/java/com/techfork/global/constant/RedisKey.java

@@ -4,5 +4,6 @@ public final class RedisKey {
     private RedisKey() {}
 
     public static final String REFRESH_TOKEN_PREFIX = "refreshToken:";
+    public static final String USER_AUTH_PREFIX = "user:auth:";
     public static final String CRAWLING_LOCK_KEY = "rss-crawling";
 }

src/main/java/com/techfork/global/security/auth/service/UserAuthCacheService.java

@@ -0,0 +1,71 @@
+package com.techfork.global.security.auth.service;
+
+import com.techfork.domain.user.entity.User;
+import com.techfork.domain.user.enums.Role;
+import com.techfork.domain.user.enums.UserStatus;
+import com.techfork.global.constant.RedisKey;
+import com.techfork.global.security.oauth.UserPrincipal;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.data.redis.core.StringRedisTemplate;
+import org.springframework.stereotype.Service;
+
+import java.util.concurrent.TimeUnit;
+
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class UserAuthCacheService {
+
+    private static final String DELIMITER = "|";
+    private static final int FIELD_COUNT = 4;
+
+    private final StringRedisTemplate redisTemplate;
+
+    public UserPrincipal get(Long userId) {
+        String key = buildKey(userId);
+        String cached = redisTemplate.opsForValue().get(key);
+        if (cached == null) {
+            return null;
+        }
+        return deserialize(cached);
+    }
+
+    public void put(Long userId, User user, long ttlMillis) {
+        String key = buildKey(userId);
+        String value = serialize(user);
+        redisTemplate.opsForValue().set(key, value, ttlMillis, TimeUnit.MILLISECONDS);
+        log.debug("User auth cached for userId: {}", userId);
+    }
+
+    public void evict(Long userId) {
+        String key = buildKey(userId);
+        redisTemplate.delete(key);
+        log.debug("User auth cache evicted for userId: {}", userId);
+    }
+
+    private String buildKey(Long userId) {
+        return RedisKey.USER_AUTH_PREFIX + userId;
+    }
+
+    private String serialize(User user) {
+        return user.getId()
+                + DELIMITER + user.getRole().name()
+                + DELIMITER + user.getStatus().name()
+                + DELIMITER + (user.getEmail() != null ? user.getEmail() : "");
+    }
+
+    private UserPrincipal deserialize(String value) {
+        String[] parts = value.split("\\" + DELIMITER, FIELD_COUNT);
+        if (parts.length != FIELD_COUNT) {
+            log.warn("Invalid user auth cache format: {}", value);
+            return null;
+        }
+        return UserPrincipal.builder()
+                .id(Long.parseLong(parts[0]))
+                .role(Role.valueOf(parts[1]))
+                .status(UserStatus.valueOf(parts[2]))
+                .email(parts[3].isEmpty() ? null : parts[3])
+                .build();
+    }
+}

src/main/java/com/techfork/global/security/filter/JwtAuthenticationFilter.java

@@ -2,10 +2,13 @@
 
 import com.techfork.domain.auth.exception.AuthErrorCode;
 import com.techfork.domain.user.entity.User;
+import com.techfork.domain.user.enums.UserStatus;
 import com.techfork.domain.user.repository.UserRepository;
 import com.techfork.global.constant.Constants;
 import com.techfork.global.constant.MdcKey;
 import com.techfork.global.exception.GeneralException;
+import com.techfork.global.security.auth.service.UserAuthCacheService;
+import com.techfork.global.security.jwt.JwtProperties;
 import com.techfork.global.security.jwt.JwtUtil;
 import com.techfork.global.security.oauth.UserPrincipal;
 import com.techfork.global.util.HeaderUtil;
@@ -40,6 +43,8 @@ public class JwtAuthenticationFilter extends OncePerRequestFilter {
 
     private final JwtUtil jwtUtil;
     private final UserRepository userRepository;
+    private final UserAuthCacheService userAuthCacheService;
+    private final JwtProperties jwtProperties;
 
     @Override
     protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
@@ -54,14 +59,23 @@ protected void doFilterInternal(HttpServletRequest request, HttpServletResponse
                 jwtUtil.validateTokenType(jwt, TOKEN_TYPE_ACCESS);
 
                 Long userId = jwtUtil.getUserIdFromToken(jwt);
-                User user = userRepository.findById(userId)
-                        .orElseThrow(() -> new GeneralException(AuthErrorCode.USER_NOT_FOUND));
+                UserPrincipal userPrincipal = userAuthCacheService.get(userId);
 
-                if (user.isWithdrawn()) {
+                if (userPrincipal == null) {
+                    User user = userRepository.findById(userId)
+                            .orElseThrow(() -> new GeneralException(AuthErrorCode.USER_NOT_FOUND));
+
+                    userPrincipal = UserPrincipal.buildUserPrincipal(user);
+
+                    if (userPrincipal.getStatus() == UserStatus.WITHDRAWN) {
+                        throw new GeneralException(AuthErrorCode.WITHDRAWN_USER);
+                    }
+
+                    userAuthCacheService.put(userId, user, jwtProperties.getAccessTokenExpiration());
+                } else if (userPrincipal.getStatus() == UserStatus.WITHDRAWN) {
                     throw new GeneralException(AuthErrorCode.WITHDRAWN_USER);
                 }
 
-                UserPrincipal userPrincipal = UserPrincipal.buildUserPrincipal(user);
                 UsernamePasswordAuthenticationToken authentication = createAuthentication(userPrincipal, request);
 
                 SecurityContext securityContext = SecurityContextHolder.createEmptyContext();

src/test/java/com/techfork/domain/auth/service/AuthServiceTest.java

@@ -13,6 +13,7 @@
 import com.techfork.domain.user.repository.UserRepository;
 import com.techfork.global.exception.GeneralException;
 import com.techfork.global.security.auth.service.RefreshTokenService;
+import com.techfork.global.security.auth.service.UserAuthCacheService;
 import com.techfork.global.security.jwt.JwtDTO;
 import com.techfork.global.security.jwt.JwtProperties;
 import com.techfork.global.security.jwt.JwtUtil;
@@ -60,6 +61,9 @@ class AuthServiceTest {
     @Mock
     private KakaoOAuthService kakaoOAuthService;
 
+    @Mock
+    private UserAuthCacheService userAuthCacheService;
+
     @InjectMocks
     private AuthService authService;
 
@@ -96,6 +100,7 @@ void refreshToken_Success() {
         given(userRepository.findById(userId)).willReturn(Optional.of(user));
         given(jwtUtil.generateTokens(userId, Role.USER)).willReturn(newTokens);
         given(jwtProperties.getRefreshTokenExpiration()).willReturn(900000L);
+        given(jwtProperties.getAccessTokenExpiration()).willReturn(180000L);
 
         // When
         TokenRefreshResponse result = authService.refreshToken(validRefreshToken, response);
@@ -105,6 +110,7 @@ void refreshToken_Success() {
         verify(jwtUtil).isValidToken(validRefreshToken);
         verify(jwtUtil).validateTokenType(validRefreshToken, TOKEN_TYPE_REFRESH);
         verify(refreshTokenService).saveRefreshToken(eq(userId), eq(newRefreshToken), anyLong());
+        verify(userAuthCacheService).put(eq(userId), eq(user), eq(180000L));
         verify(response).addHeader(eq("Set-Cookie"), anyString());
     }
 

src/test/java/com/techfork/domain/user/service/UserCommandServiceTest.java

@@ -9,6 +9,7 @@
 import com.techfork.domain.user.exception.UserErrorCode;
 import com.techfork.domain.user.repository.UserRepository;
 import com.techfork.global.exception.GeneralException;
+import com.techfork.global.security.auth.service.UserAuthCacheService;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -40,6 +41,9 @@ class UserCommandServiceTest {
     @Mock
     private UserRepository userRepository;
 
+    @Mock
+    private UserAuthCacheService userAuthCacheService;
+
     @InjectMocks
     private UserCommandService userCommandService;
 
@@ -81,6 +85,7 @@ void completeOnboarding_Success() {
 
         verify(userRepository, times(1)).findByIdWithInterestCategories(userId);
         verify(interestCommandService, times(1)).saveUserInterests(eq(mockUser), any(SaveInterestRequest.class));
+        verify(userAuthCacheService).evict(userId);
     }
 
     @Test
@@ -142,6 +147,7 @@ void completeOnboarding_NullDescription_Success() {
         assertThat(mockUser.getDescription()).isNull();
 
         verify(interestCommandService, times(1)).saveUserInterests(eq(mockUser), any(SaveInterestRequest.class));
+        verify(userAuthCacheService).evict(userId);
     }
 
     @Test
@@ -182,6 +188,7 @@ void completeOnboarding_MultipleCategories_Success() {
         // Then
         assertThat(mockUser.getNickName()).isEqualTo("풀스택개발자");
         verify(interestCommandService, times(1)).saveUserInterests(eq(mockUser), any(SaveInterestRequest.class));
+        verify(userAuthCacheService).evict(userId);
     }
 
     // ===== 프로필 수정 테스트 =====
@@ -308,6 +315,7 @@ void withdrawUser_Success() {
         assertThat(testUser.getSocialId()).isEqualTo(originalSocialId);
 
         verify(userRepository).findById(userId);
+        verify(userAuthCacheService).evict(userId);
     }
 
     @Test