feat: 애플 로그인 기능 추가

build.gradle

@@ -46,7 +46,7 @@ dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-aop'
 
     implementation 'org.springframework.boot:spring-boot-starter-security'
-    compileOnly group: 'io.jsonwebtoken', name: 'jjwt-api', version: '0.11.2'
+    implementation group: 'io.jsonwebtoken', name: 'jjwt-api', version: '0.11.2'
     runtimeOnly group: 'io.jsonwebtoken', name: 'jjwt-impl', version: '0.11.2'
     runtimeOnly group: 'io.jsonwebtoken', name: 'jjwt-jackson', version: '0.11.2'
 

src/main/java/com/recipe/app/src/common/client/apple/AppleOAuthFeignClient.java

@@ -0,0 +1,13 @@
+package com.recipe.app.src.common.client.apple;
+
+import com.recipe.app.src.common.client.apple.dto.ApplePublicKeysResponse;
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.web.bind.annotation.GetMapping;
+
+@FeignClient(name = "apple-oauth-client", url = "https://appleid.apple.com/auth")
+public interface AppleOAuthFeignClient {
+
+    @GetMapping(value = "/keys")
+    ApplePublicKeysResponse getPublicKeys();
+
+}

src/main/java/com/recipe/app/src/common/client/apple/dto/AppleAuthResponse.java

@@ -0,0 +1,24 @@
+package com.recipe.app.src.common.client.apple.dto;
+
+import com.recipe.app.src.user.domain.User;
+import lombok.Builder;
+import lombok.Getter;
+
+@Getter
+@Builder
+public class AppleAuthResponse {
+
+    private String sub;
+    private String email;
+    private String name;
+
+    public User toEntity(String fcmToken) {
+
+        return User.builder()
+                .socialId("apple_" + sub)
+                .nickname(name != null ? name : "Apple User")
+                .email(email)
+                .deviceToken(fcmToken)
+                .build();
+    }
+}

src/main/java/com/recipe/app/src/common/client/apple/dto/ApplePublicKeyResponse.java

@@ -0,0 +1,14 @@
+package com.recipe.app.src.common.client.apple.dto;
+
+import lombok.Getter;
+
+@Getter
+public class ApplePublicKeyResponse {
+
+    private String kty;
+    private String kid;
+    private String use;
+    private String alg;
+    private String n;
+    private String e;
+}

src/main/java/com/recipe/app/src/common/client/apple/dto/ApplePublicKeysResponse.java

@@ -0,0 +1,20 @@
+package com.recipe.app.src.common.client.apple.dto;
+
+import lombok.Getter;
+
+import java.util.List;
+
+@Getter
+public class ApplePublicKeysResponse {
+
+    private List<ApplePublicKeyResponse> keys;
+
+    public ApplePublicKeyResponse getMatchKey(String alg, String kid) {
+
+        return this.keys
+                .stream()
+                .filter(key -> key.getAlg().equals(alg) && key.getKid().equals(kid))
+                .findFirst()
+                .orElseThrow(() -> new IllegalArgumentException("Apple 로그인 시 필요한 key 값이 존재하지 않습니다."));
+    }
+}

src/main/java/com/recipe/app/src/common/utils/JwtUtil.java

@@ -1,5 +1,6 @@
 package com.recipe.app.src.common.utils;
 
+import com.recipe.app.src.common.client.apple.dto.ApplePublicKeyResponse;
 import io.jsonwebtoken.*;
 import io.jsonwebtoken.security.SignatureException;
 import jakarta.servlet.http.HttpServletRequest;
@@ -12,7 +13,11 @@
 import org.springframework.util.StringUtils;
 
 import javax.crypto.spec.SecretKeySpec;
+import java.math.BigInteger;
 import java.security.Key;
+import java.security.KeyFactory;
+import java.security.PublicKey;
+import java.security.spec.RSAPublicKeySpec;
 import java.time.Duration;
 import java.util.Base64;
 import java.util.Date;
@@ -135,4 +140,39 @@ public void setAccessTokenBlacklist(String accessToken) {
 
         redisTemplate.opsForValue().set(accessToken, ACCESS_TOKEN_BLACKLIST_VALUE, Duration.ofMillis(accessTokenValidMillisecond));
     }
+
+    public Claims parseAppleIdToken(String idToken, ApplePublicKeyResponse publicKey) {
+
+        try {
+            PublicKey key = generateApplePublicKey(publicKey);
+
+            return Jwts.parserBuilder()
+                    .setSigningKey(key)
+                    .build()
+                    .parseClaimsJws(idToken)
+                    .getBody();
+        } catch (Exception e) {
+            logger.error("Apple id_token 검증 실패", e);
+            throw new IllegalArgumentException("Apple id_token 검증에 실패했습니다.", e);
+        }
+    }
+
+    private PublicKey generateApplePublicKey(ApplePublicKeyResponse publicKey) {
+
+        try {
+            byte[] nBytes = Base64.getUrlDecoder().decode(publicKey.getN());
+            byte[] eBytes = Base64.getUrlDecoder().decode(publicKey.getE());
+
+            BigInteger n = new BigInteger(1, nBytes);
+            BigInteger e = new BigInteger(1, eBytes);
+
+            RSAPublicKeySpec publicKeySpec = new RSAPublicKeySpec(n, e);
+            KeyFactory keyFactory = KeyFactory.getInstance(publicKey.getKty());
+
+            return keyFactory.generatePublic(publicKeySpec);
+        } catch (Exception exception) {
+            logger.error("Apple Public Key 생성 실패", exception);
+            throw new IllegalArgumentException("Apple Public Key 생성에 실패했습니다.", exception);
+        }
+    }
 }

src/main/java/com/recipe/app/src/user/api/UserController.java

@@ -77,6 +77,14 @@ public UserSocialLoginResponse googleLogin(@Parameter(name = "로그인 요청 
         return userService.googleLogin(request);
     }
 
+    @Operation(summary = "애플 로그인 API")
+    @PostMapping("/apple-login")
+    public UserSocialLoginResponse appleLogin(@Parameter(name = "로그인 요청 정보", required = true)
+                                               @RequestBody UserLoginRequest request) {
+
+        return userService.appleLogin(request);
+    }
+
     @Operation(summary = "유저 프로필 조회 API")
     @GetMapping
     @LoginCheck

src/main/java/com/recipe/app/src/user/application/UserAuthClientService.java

@@ -1,17 +1,27 @@
 package com.recipe.app.src.user.application;
 
+import com.recipe.app.src.common.client.apple.AppleOAuthFeignClient;
+import com.recipe.app.src.common.client.apple.dto.AppleAuthResponse;
+import com.recipe.app.src.common.client.apple.dto.ApplePublicKeyResponse;
+import com.recipe.app.src.common.client.apple.dto.ApplePublicKeysResponse;
 import com.recipe.app.src.common.client.google.GoogleOAuthFeignClient;
 import com.recipe.app.src.common.client.kakao.KakaoFeignClient;
 import com.recipe.app.src.common.client.kakao.KakaoOAuthFeignClient;
 import com.recipe.app.src.common.client.naver.NaverFeignClient;
 import com.recipe.app.src.common.client.naver.NaverOAuthFeignClient;
 import com.recipe.app.src.common.client.naver.dto.NaverAuthResponse;
+import com.recipe.app.src.common.utils.JwtUtil;
 import com.recipe.app.src.user.application.dto.UserLoginRequest;
 import com.recipe.app.src.user.domain.User;
 import com.recipe.app.src.user.exception.ForbiddenAccessException;
+import io.jsonwebtoken.Claims;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 
+import java.util.Base64;
+
 @Service
 public class UserAuthClientService {
 
@@ -32,20 +42,26 @@ public class UserAuthClientService {
     @Value("${google.redirect-uri}")
     private String googleRedirectURI;
 
+    private final Logger logger = LoggerFactory.getLogger(UserAuthClientService.class);
     private final NaverFeignClient naverFeignClient;
     private final NaverOAuthFeignClient naverOAuthFeignClient;
     private final KakaoFeignClient kakaoFeignClient;
     private final KakaoOAuthFeignClient kakaoOAuthFeignClient;
     private final GoogleOAuthFeignClient googleOAuthFeignClient;
+    private final AppleOAuthFeignClient appleOAuthFeignClient;
+    private final JwtUtil jwtUtil;
 
     public UserAuthClientService(NaverFeignClient naverFeignClient, NaverOAuthFeignClient naverOAuthFeignClient,
                                  KakaoFeignClient kakaoFeignClient, KakaoOAuthFeignClient kakaoOAuthFeignClient,
-                                 GoogleOAuthFeignClient googleOAuthFeignClient) {
+                                 GoogleOAuthFeignClient googleOAuthFeignClient, AppleOAuthFeignClient appleOAuthFeignClient,
+                                 JwtUtil jwtUtil) {
         this.naverFeignClient = naverFeignClient;
         this.naverOAuthFeignClient = naverOAuthFeignClient;
         this.kakaoFeignClient = kakaoFeignClient;
         this.kakaoOAuthFeignClient = kakaoOAuthFeignClient;
         this.googleOAuthFeignClient = googleOAuthFeignClient;
+        this.appleOAuthFeignClient = appleOAuthFeignClient;
+        this.jwtUtil = jwtUtil;
     }
 
     public UserLoginRequest getNaverLoginRequest(String code, String state) {
@@ -101,4 +117,59 @@ public User getUserByGoogleAuthInfo(UserLoginRequest request) {
         return googleOAuthFeignClient.getAuthInfo(request.getAccessToken())
                 .toEntity(request.getFcmToken());
     }
+
+    public User getUserByAppleAuthInfo(UserLoginRequest request) {
+
+        String idToken = request.getAccessToken();
+
+        // 1. Apple Public Keys 조회
+        ApplePublicKeysResponse publicKeys = appleOAuthFeignClient.getPublicKeys();
+
+        // 2. id_token 헤더에서 kid, alg 추출
+        String kid = getKidFromIdToken(idToken);
+        String alg = getAlgFromIdToken(idToken);
+
+        // 3. 매칭되는 Public Key 찾기
+        ApplePublicKeyResponse matchedKey = publicKeys.getMatchKey(alg, kid);
+
+        // 4. JWT 검증 및 Claims 추출
+        Claims claims = jwtUtil.parseAppleIdToken(idToken, matchedKey);
+
+        // 5. User 엔티티 생성
+        return AppleAuthResponse.builder()
+                .sub(claims.get("sub", String.class))
+                .email(claims.get("email", String.class))
+                .name(null)
+                .build()
+                .toEntity(request.getFcmToken());
+    }
+
+    public String getKidFromIdToken(String idToken) {
+
+        try {
+            String header = idToken.split("\\.")[0];
+            String decodedHeader = new String(Base64.getUrlDecoder().decode(header));
+
+            String kid = decodedHeader.split("\"kid\":\"")[1].split("\"")[0];
+            return kid;
+        } catch (Exception e) {
+            logger.error("id_token 헤더에서 kid 추출 실패", e);
+            throw new IllegalArgumentException("id_token 헤더에서 kid를 추출할 수 없습니다.", e);
+        }
+    }
+
+    private String getAlgFromIdToken(String idToken) {
+
+        try {
+            String header = idToken.split("\\.")[0];
+            String decodedHeader = new String(Base64.getUrlDecoder().decode(header));
+
+            String alg = decodedHeader.split("\"alg\":\"")[1].split("\"")[0];
+            return alg;
+        } catch (Exception e) {
+            logger.error("id_token 헤더에서 alg 추출 실패", e);
+            throw new IllegalArgumentException("id_token 헤더에서 alg를 추출할 수 없습니다.", e);
+        }
+    }
+
 }

src/main/java/com/recipe/app/src/user/application/UserService.java

@@ -1,8 +1,8 @@
 package com.recipe.app.src.user.application;
 
 import com.google.common.base.Preconditions;
-import com.recipe.app.src.common.utils.JwtUtil;
 import com.recipe.app.src.common.utils.BadWordFiltering;
+import com.recipe.app.src.common.utils.JwtUtil;
 import com.recipe.app.src.user.application.dto.UserDeviceTokenRequest;
 import com.recipe.app.src.user.application.dto.UserLoginRequest;
 import com.recipe.app.src.user.application.dto.UserLoginResponse;
@@ -97,6 +97,21 @@ public UserSocialLoginResponse googleLogin(UserLoginRequest request) {
         return UserSocialLoginResponse.from(user, accessToken, refreshToken);
     }
 
+    @Transactional
+    public UserSocialLoginResponse appleLogin(UserLoginRequest request) {
+
+        Preconditions.checkArgument(StringUtils.hasText(request.getAccessToken()), "id_token을 입력해주세요.");
+
+        User user = create(userAuthClientService.getUserByAppleAuthInfo(request));
+
+        user.changeRecentLoginAt(LocalDateTime.now());
+
+        String accessToken = jwtUtil.createAccessToken(user.getUserId());
+        String refreshToken = jwtUtil.createRefreshToken(user.getUserId());
+
+        return UserSocialLoginResponse.from(user, accessToken, refreshToken);
+    }
+
     private User create(User user) {
 
         return userRepository.findBySocialId(user.getSocialId())