Merge pull request #140 from Me1tingPot/feature/#128

�[Refactor] 카카오 로그인 SDK 방식으로 변경

src/main/java/meltingpot/server/auth/controller/dto/OAuthSignInRequestDto.java

@@ -4,7 +4,7 @@
 
 public record OAuthSignInRequestDto(
         OAuthType type,
-        String code,
+        String token,
         String push_token
 ) {
 }

src/main/java/meltingpot/server/auth/oauth/kakao/KakaoDto.java

@@ -5,8 +5,6 @@
 @Builder
 @Data
 public class KakaoDto {
-
-    private long id;
     private String email;
     private String nickname;
 

src/main/java/meltingpot/server/auth/oauth/kakao/KakaoService.java

@@ -1,5 +1,7 @@
 package meltingpot.server.auth.oauth.kakao;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.json.simple.JSONObject;
 import org.json.simple.parser.JSONParser;
 import org.springframework.beans.factory.annotation.Value;
@@ -11,6 +13,7 @@
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
 import org.springframework.web.client.RestTemplate;
+import java.util.Base64;
 
 @Service
 public class KakaoService {
@@ -26,16 +29,17 @@ public class KakaoService {
 
     private final static String KAKAO_AUTH_URI = "https://kauth.kakao.com";
     private final static String KAKAO_API_URI = "https://kapi.kakao.com";
+    private final ObjectMapper objectMapper = new ObjectMapper();
 
     public String getKakaoLogin(String redirect_uri) { // 프론트 구현부
         return KAKAO_AUTH_URI + "/oauth/authorize"
                 + "?client_id=" + KAKAO_CLIENT_ID
                 + "&redirect_uri=" + redirect_uri
-                + "&response_type=code";
+                + "&response_type=token";
     }
 
-    public KaKaoTokenDto getKakaoInfo(String code) throws Exception {
-        if (code == null) throw new Exception("Failed get authorization code");
+    public KaKaoTokenDto getKakaoToken(String code) throws Exception {
+        if (code == null) throw new Exception("Failed get authorization token");
 
         String accessToken = "";
         String refreshToken = "";
@@ -48,7 +52,7 @@ public KaKaoTokenDto getKakaoInfo(String code) throws Exception {
             params.add("grant_type"   , "authorization_code");
             params.add("client_id"    , KAKAO_CLIENT_ID);
             params.add("client_secret", KAKAO_CLIENT_SECRET);
-            params.add("code"         , code);
+            params.add("token"         , code);
             params.add("redirect_uri" , redirect_uri);
 
             RestTemplate restTemplate = new RestTemplate();
@@ -103,7 +107,30 @@ public KakaoDto getUserInfoWithToken(String accessToken) throws Exception {
         String nickname = String.valueOf(profile.get("nickname"));
 
         return KakaoDto.builder()
-                .id(id)
+                .email(email)
+                .nickname(nickname).build();
+    }
+
+    public KakaoDto getUserInfoFromIdToken(String idToken) throws Exception {
+        // 온점 분리
+        String[] parts = idToken.split("\\.");
+        if (parts.length != 3) {
+            throw new IllegalArgumentException("Invalid IdToken");
+        }
+
+        // Payload 디코딩
+        String payload = parts[1];
+        String decodedPayload = new String(Base64.getDecoder().decode(payload));
+
+        // JSON 파싱
+        JsonNode jsonNode = objectMapper.readTree(decodedPayload);
+
+        // email과 nickname 추출
+        String email = jsonNode.path("email").asText(null);
+        String nickname = jsonNode.path("nickname").asText(null);
+
+        // 정보 담아 보내기
+        return KakaoDto.builder()
                 .email(email)
                 .nickname(nickname).build();
     }

src/main/java/meltingpot/server/auth/service/OAuthService.java

@@ -2,12 +2,10 @@
 
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import meltingpot.server.auth.controller.dto.AccountResponseDto;
 import meltingpot.server.auth.controller.dto.OAuthSignInRequestDto;
 import meltingpot.server.auth.controller.dto.OAuthSignupRequestDto;
 import meltingpot.server.auth.controller.dto.ProfileImageRequestDto;
 import meltingpot.server.auth.oauth.OAuthUserDetails;
-import meltingpot.server.auth.oauth.kakao.KaKaoTokenDto;
 import meltingpot.server.auth.oauth.kakao.KakaoDto;
 import meltingpot.server.auth.oauth.kakao.KakaoService;
 import meltingpot.server.auth.service.dto.OAuthSignInResponseDto;
@@ -20,16 +18,12 @@
 import meltingpot.server.domain.repository.RefreshTokenRepository;
 import meltingpot.server.exception.AuthException;
 import meltingpot.server.exception.IllegalArgumentException;
-import meltingpot.server.exception.ResourceNotFoundException;
 import meltingpot.server.util.ResponseCode;
 import meltingpot.server.util.TokenDto;
-import meltingpot.server.util.r2.FileService;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
-import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
 import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContextHolder;
-import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
@@ -109,6 +103,7 @@ public OAuthSignInResponseDto oauthSignup(OAuthSignupRequestDto signupRequest) {
                         .build()).toList()
         );
 
+
         account.setLanguages(signupRequest.languages().stream().map(
                 (language) -> AccountLanguage.builder()
                         .account(account)
@@ -132,11 +127,17 @@ public OAuthSignInResponseDto oauthSignup(OAuthSignupRequestDto signupRequest) {
     public OAuthSignInResponseDto SNSLogin(OAuthSignInRequestDto request) throws Exception {
 
         if(request.type() == OAuthType.KAKAO) {
+
+            /* * * * RestAPI 버전 * * * /
             // 카카오 토큰 가져오기
-            KaKaoTokenDto tokenDto = kakaoService.getKakaoInfo(request.code());
+            KaKaoTokenDto tokenDto = kakaoService.getKakaoToken(request.token());
 
             // 카카오 유저 정보 가져오기
-            KakaoDto kakaoDto = kakaoService.getUserInfoWithToken(tokenDto.accessToken());
+            KakaoDto kakaoDto = kakaoService.getUserInfoWithToken(request.token());
+             * * * * * * * * * * * * */
+
+            // SDK 버전: 아이디토큰으로 유저 정보 파싱해오기
+            KakaoDto kakaoDto = kakaoService.getUserInfoFromIdToken(request.token());
 
             // 이미 가입한 회원인지 확인
             Optional<Account> account = accountRepository.findByUsernameAndIsQuitIsFalse(kakaoDto.getEmail());