Feat/#56/카카오 액세스 토큰 구조

src/main/java/plango/auth/application/dto/request/KakaoLoginRequest.java

@@ -4,10 +4,13 @@
 
 /**
  * 카카오 로그인 요청 DTO
- *  - authorizationCode : 카카오 인가 코드 (authorization_code)
+ * Android 카카오 SDK에서 발급받은 accessToken, idToken을 전달합니다.
+ * idToken은 선택값이며 현재 서버에서는 accessToken을 기반으로 카카오 사용자 정보를 조회합니다.
  */
 public record KakaoLoginRequest(
-        @NotBlank(message = "카카오 인가 코드는 필수입니다.")
-        String authorizationCode
+        @NotBlank(message = "카카오 access token은 필수입니다.")
+        String accessToken,
+        String idToken
 ) {
 }
+

src/main/java/plango/auth/application/usecase/KakaoLoginUseCase.java

@@ -27,8 +27,8 @@ public class KakaoLoginUseCase {
 
     @Transactional
     public KakaoLoginResponse execute(KakaoLoginRequest request) {
-        KakaoUserInfoResponse userInfo = kakaoAuthService.getUserInfoByAuthorizationCode(
-                request.authorizationCode()
+        KakaoUserInfoResponse userInfo = kakaoAuthService.getUserInfoByAccessToken(
+                request.accessToken()
         );
 
         String email = userInfo.getEmail();
@@ -70,3 +70,4 @@ public KakaoLoginResponse execute(KakaoLoginRequest request) {
         );
     }
 }
+

src/main/java/plango/auth/domain/service/KakaoAuthService.java

@@ -1,5 +1,6 @@
 package plango.auth.domain.service;
 
+import jakarta.annotation.PostConstruct;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
@@ -19,15 +20,12 @@
 import plango.global.common.exception.BusinessException;
 import plango.global.common.exception.ErrorCode;
 
-import jakarta.annotation.PostConstruct;
-
 @Slf4j
 @Service
 @RequiredArgsConstructor
 public class KakaoAuthService {
 
     private static final String KAKAO_TOKEN_URI = "https://kauth.kakao.com/oauth/token";
-
     private static final String KAKAO_USER_INFO_URI = "https://kapi.kakao.com/v2/user/me";
 
     @Value("${security.oauth2.kakao.client-id}")
@@ -45,57 +43,80 @@ public void printConfig() {
         log.info("redirectUri = {}", redirectUri);
     }
 
+    /**
+     * (웹용) 인가 코드를 이용해 카카오 사용자 정보를 조회하는 메서드
+     */
     public KakaoUserInfoResponse getUserInfoByAuthorizationCode(String authorizationCode) {
         KakaoTokenResponse tokenResponse = requestToken(authorizationCode);
         String accessToken = tokenResponse.accessToken();
         log.info("accessToken from Kakao = {}", accessToken);
         return requestUserInfo(accessToken);
     }
 
+    /**
+     * (모바일용) 이미 발급받은 accessToken 으로 바로 사용자 정보 조회
+     */
+    public KakaoUserInfoResponse getUserInfoByAccessToken(String accessToken) {
+        return requestUserInfo(accessToken);
+    }
+
     private KakaoTokenResponse requestToken(String authorizationCode) {
         HttpHeaders headers = new HttpHeaders();
         headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
+
         MultiValueMap<String, String> body = new LinkedMultiValueMap<>();
         body.add("grant_type", "authorization_code");
         body.add("client_id", clientId);
         body.add("redirect_uri", redirectUri);
         body.add("code", authorizationCode);
+
         log.info("requestToken() body = {}", body);
+
         HttpEntity<MultiValueMap<String, String>> entity = new HttpEntity<>(body, headers);
+
         try {
             ResponseEntity<KakaoTokenResponse> response = restTemplate.postForEntity(
                     KAKAO_TOKEN_URI,
                     entity,
                     KakaoTokenResponse.class
             );
+
             log.info("requestToken() status = {}", response.getStatusCode());
+
             KakaoTokenResponse tokenResponse = response.getBody();
+
             if (!response.getStatusCode().is2xxSuccessful() || tokenResponse == null) {
                 throw new BusinessException(
                         ErrorCode.KAKAO_SERVER_ERROR.getStatusCode(),
                         ErrorCode.KAKAO_SERVER_ERROR.getMessage()
                 );
             }
+
             if (tokenResponse.accessToken() == null || tokenResponse.accessToken().isBlank()) {
                 log.error("Kakao token response has no access_token. body = {}", tokenResponse);
                 throw new BusinessException(
                         ErrorCode.KAKAO_SERVER_ERROR.getStatusCode(),
                         ErrorCode.KAKAO_SERVER_ERROR.getMessage()
                 );
             }
+
             return tokenResponse;
         } catch (RestClientResponseException exception) {
-            log.error("Kakao token request error. status = {}, body = {}",
+            log.error(
+                    "Kakao token request error. status = {}, body = {}",
                     exception.getRawStatusCode(),
                     exception.getResponseBodyAsString()
             );
+
             ErrorCode errorCode = selectErrorCode(exception.getRawStatusCode());
+
             throw new BusinessException(
                     errorCode.getStatusCode(),
                     errorCode.getMessage()
             );
         } catch (RestClientException exception) {
             log.error("Kakao token request RestClientException", exception);
+
             throw new BusinessException(
                     ErrorCode.KAKAO_SERVER_ERROR.getStatusCode(),
                     ErrorCode.KAKAO_SERVER_ERROR.getMessage()
@@ -106,34 +127,43 @@ private KakaoTokenResponse requestToken(String authorizationCode) {
     private KakaoUserInfoResponse requestUserInfo(String accessToken) {
         HttpHeaders headers = createBearerHeaders(accessToken);
         HttpEntity<Void> entity = new HttpEntity<>(headers);
+
         try {
             ResponseEntity<KakaoUserInfoResponse> response = restTemplate.exchange(
                     KAKAO_USER_INFO_URI,
                     HttpMethod.GET,
                     entity,
                     KakaoUserInfoResponse.class
             );
+
             log.info("requestUserInfo() status = {}", response.getStatusCode());
+
             KakaoUserInfoResponse userInfo = response.getBody();
+
             if (!response.getStatusCode().is2xxSuccessful() || userInfo == null) {
                 throw new BusinessException(
                         ErrorCode.KAKAO_SERVER_ERROR.getStatusCode(),
                         ErrorCode.KAKAO_SERVER_ERROR.getMessage()
                 );
             }
+
             return userInfo;
         } catch (RestClientResponseException exception) {
-            log.error("Kakao userInfo request error. status = {}, body = {}",
+            log.error(
+                    "Kakao userInfo request error. status = {}, body = {}",
                     exception.getRawStatusCode(),
                     exception.getResponseBodyAsString()
             );
+
             ErrorCode errorCode = selectErrorCode(exception.getRawStatusCode());
+
             throw new BusinessException(
                     errorCode.getStatusCode(),
                     errorCode.getMessage()
             );
         } catch (RestClientException exception) {
             log.error("Kakao userInfo request RestClientException", exception);
+
             throw new BusinessException(
                     ErrorCode.KAKAO_SERVER_ERROR.getStatusCode(),
                     ErrorCode.KAKAO_SERVER_ERROR.getMessage()
@@ -152,6 +182,8 @@ private ErrorCode selectErrorCode(int statusCode) {
         if (statusCode == 401) {
             return ErrorCode.KAKAO_INVALID_TOKEN;
         }
+
         return ErrorCode.KAKAO_SERVER_ERROR;
     }
 }
+

src/main/java/plango/auth/presentation/AuthController.java

@@ -94,7 +94,10 @@ public ResponseEntity<CommonResponse<KakaoLoginResponse>> login(
         );
     }
 
-    @Operation(summary = "카카오 로그인", description = "카카오 인가 코드를 사용해 로그인합니다.")
+    @Operation(
+            summary = "카카오 로그인",
+            description = "Android 카카오 SDK에서 발급받은 accessToken을 사용해 로그인합니다."
+    )
     @PostMapping("/login/kakao")
     public ResponseEntity<CommonResponse<KakaoLoginResponse>> kakaoLogin(
             @Valid