✨ [feat] OAuth2 로그인, 회원가입 기능 구현

build.gradle

@@ -56,6 +56,15 @@ dependencies {
     implementation 'io.jsonwebtoken:jjwt-api:0.12.3'
     implementation 'io.jsonwebtoken:jjwt-impl:0.12.3'
     implementation 'io.jsonwebtoken:jjwt-jackson:0.12.3'
+
+    // OAuth2 login
+    implementation 'org.springframework.boot:spring-boot-starter-oauth2-client'
+
+    // WebClient
+    implementation 'org.springframework.boot:spring-boot-starter-webflux'
+
+    // Netty
+    implementation 'io.netty:netty-resolver-dns-native-macos:4.1.68.Final:osx-aarch_64'
 }
 
 tasks.named('test') {

src/main/java/com/example/umc8th/domain/member/controller/MemberController.java

@@ -3,14 +3,12 @@
 import com.example.umc8th.domain.member.dto.request.MemberRequestDTO;
 import com.example.umc8th.domain.member.dto.response.MemberResponseDTO;
 import com.example.umc8th.domain.member.service.command.MemberCommandService;
+import com.example.umc8th.domain.member.service.command.OAuth2Service;
 import com.example.umc8th.global.apiPayload.CustomResponse;
 import com.example.umc8th.global.jwt.dto.JwtDTO;
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.HttpStatus;
-import org.springframework.web.bind.annotation.PostMapping;
-import org.springframework.web.bind.annotation.RequestBody;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.*;
 
 @RestController
 @RequestMapping("/auth")

src/main/java/com/example/umc8th/domain/member/controller/OAuth2Controller.java

@@ -0,0 +1,22 @@
+package com.example.umc8th.domain.member.controller;
+
+import com.example.umc8th.domain.member.service.command.OAuth2Service;
+import com.example.umc8th.global.apiPayload.CustomResponse;
+import com.example.umc8th.global.jwt.dto.JwtDTO;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequiredArgsConstructor
+public class OAuth2Controller {
+
+    private final OAuth2Service oAuth2Service;
+
+    @GetMapping("/oauth2/callback/kakao")
+    public CustomResponse<JwtDTO> loginWithKakao(@RequestParam("code") String code) {
+        JwtDTO jwtDTO = oAuth2Service.loginWithKakao(code);
+        return CustomResponse.onSuccess(jwtDTO);
+    }
+}

src/main/java/com/example/umc8th/domain/member/converter/MemberConverter.java

@@ -14,13 +14,15 @@ public class MemberConverter {
     public static MemberResponseDTO.SignUp toSignUpResponseDTO(Member member) {
         return MemberResponseDTO.SignUp.builder()
                 .id(member.getId())
+                .email(member.getEmail())
                 .username(member.getUsername())
                 .build();
     }
 
     // SignUpRequestDTO -> Member
     public static Member toMember(MemberRequestDTO.SignUp reqDTO, PasswordEncoder passwordEncoder) {
         return Member.builder()
+                .email(reqDTO.email())
                 .username(reqDTO.username())
                 .password(passwordEncoder.encode(reqDTO.password()))
                 .build();

src/main/java/com/example/umc8th/domain/member/dto/request/MemberRequestDTO.java

@@ -3,13 +3,14 @@
 public class MemberRequestDTO {
 
     public record SignUp(
+            String email,
             String username,
             String password
     ) {
     }
 
     public record login(
-            String username,
+            String email,
             String password
     ){
     }

src/main/java/com/example/umc8th/domain/member/dto/response/MemberResponseDTO.java

@@ -7,6 +7,7 @@ public class MemberResponseDTO {
     @Builder
     public record SignUp(
             Long id,
+            String email,
             String username
     ) {
     }

src/main/java/com/example/umc8th/domain/member/dto/response/OAuth2DTO.java

@@ -0,0 +1,46 @@
+package com.example.umc8th.domain.member.dto.response;
+
+public class OAuth2DTO {
+
+    public record OAuth2TokenDTO(
+            String token_type,
+            String access_token,
+            String refresh_token,
+            Long expires_in,
+            Long refresh_token_expires_in,
+            String scope
+    ) {}
+
+    public record KakaoProfile(
+            Long id,
+            String connected_at,
+            Properties properties,
+            KakaoAccount kakao_account
+    ) {
+        public record Properties(
+                String nickname,
+                String profile_image,
+                String thumbnail_image
+        ) {}
+
+        public record KakaoAccount(
+                String email,
+                Boolean is_email_verified,
+                Boolean email_needs_agreement,
+                Boolean has_email,
+                Boolean profile_nickname_needs_agreement,
+                Boolean profile_image_needs_agreement,
+                Boolean email_needs_argument,
+                Boolean is_email_valid,
+                Profile profile
+        ) {
+            public record Profile(
+                    String nickname,
+                    String thumbnail_image_url,
+                    String profile_image_url,
+                    Boolean is_default_nickname,
+                    Boolean is_default_image
+            ) {}
+        }
+    }
+}

src/main/java/com/example/umc8th/domain/member/entity/Member.java

@@ -15,10 +15,13 @@ public class Member {
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
-    @Column(name = "username", unique = true, nullable = false)
+    @Column(name = "email")
+    private String email;
+
+    @Column(name = "username", unique = true)
     private String username;
 
-    @Column(name = "password", nullable = false)
+    @Column(name = "password")
     private String password;
 
 }

src/main/java/com/example/umc8th/domain/member/exception/MemberErrorCode.java

@@ -10,6 +10,10 @@
 public enum MemberErrorCode implements BaseErrorCode {
 
     MEMBER_NOT_FOUND(HttpStatus.NOT_FOUND, "ARTICLE404_0", "해당 사용자를 찾을 수 없습니다."),
+    OAUTH_USER_INFO_FAIL(HttpStatus.NOT_FOUND, "MEMBER404_2", "사용자 정보 조회 실패"),
+    OAUTH_TOKEN_FAIL(HttpStatus.BAD_REQUEST, "MEMBER400_1", "토큰 변환 실패"),
+    OAUTH_EMAIL_NOT_FOUND(HttpStatus.BAD_REQUEST, "MEMBER400_2", "이메일 정보를 찾을 수 없습니다."),
+    OAUTH_LOGIN_FAIL(HttpStatus.UNAUTHORIZED, "MEMBER401_1", "로그인에 실패하였습니다.")
     ;
 
     private final HttpStatus httpStatus;

src/main/java/com/example/umc8th/domain/member/repository/MemberRepository.java

@@ -8,4 +8,5 @@
 public interface MemberRepository extends JpaRepository<Member, Long> {
 
     Optional<Member> findByUsername(String username);
+    Optional<Member> findByEmail(String email);
 }

src/main/java/com/example/umc8th/domain/member/service/command/MemberCommandServiceImpl.java

@@ -35,7 +35,7 @@ public MemberResponseDTO.SignUp signUp(MemberRequestDTO.SignUp reqDTO) {
 
     @Override
     public JwtDTO login(MemberRequestDTO.login reqDTO) {
-        Member member = memberRepository.findByUsername(reqDTO.username())
+        Member member = memberRepository.findByEmail(reqDTO.email())
                 .orElseThrow(() -> new MemberException(MemberErrorCode.MEMBER_NOT_FOUND));
 
         if (!passwordEncoder.matches(reqDTO.password(), member.getPassword())) {

src/main/java/com/example/umc8th/domain/member/service/command/OAuth2Service.java

@@ -0,0 +1,8 @@
+package com.example.umc8th.domain.member.service.command;
+
+import com.example.umc8th.global.jwt.dto.JwtDTO;
+
+public interface OAuth2Service {
+
+    JwtDTO loginWithKakao(String code);
+}

src/main/java/com/example/umc8th/domain/member/service/command/OAuth2ServiceImpl.java

@@ -0,0 +1,135 @@
+package com.example.umc8th.domain.member.service.command;
+
+import com.example.umc8th.domain.member.dto.response.OAuth2DTO;
+import com.example.umc8th.domain.member.entity.Member;
+import com.example.umc8th.domain.member.exception.MemberErrorCode;
+import com.example.umc8th.domain.member.exception.MemberException;
+import com.example.umc8th.domain.member.repository.MemberRepository;
+import com.example.umc8th.global.jwt.dto.JwtDTO;
+import com.example.umc8th.global.jwt.util.JwtUtil;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatusCode;
+import org.springframework.stereotype.Service;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Mono;
+
+@Service
+@RequiredArgsConstructor
+public class OAuth2ServiceImpl implements OAuth2Service {
+
+    @Value("${spring.security.oauth2.client.provider.kakao.token-uri}")
+    private String tokenURI;
+
+    @Value("${spring.security.oauth2.client.provider.kakao.user-info-uri}")
+    private String userInfoURI;
+
+    @Value("${spring.security.oauth2.client.registration.kakao.client-id}")
+    private String clientId;
+
+    @Value("${spring.security.oauth2.client.registration.kakao.redirect-uri}")
+    private String redirectURI;
+
+    @Value("${spring.security.oauth2.client.registration.kakao.client-secret}")
+    private String clientSecret;
+
+    private final MemberRepository memberRepository;
+    private final JwtUtil jwtUtil;
+    private final WebClient webClient = WebClient.builder().build();
+
+    @Override
+    public JwtDTO loginWithKakao(String code) {
+        try {
+            // 1. Access Token 요청
+            System.out.println("Access Token 요청 중...");
+            OAuth2DTO.OAuth2TokenDTO tokenDto = getAccessToken(code);
+
+            // 2. 사용자 정보 요청
+            System.out.println("사용자 정보 요청 중...");
+            OAuth2DTO.KakaoProfile kakaoProfile = getUserInfo(tokenDto.access_token());
+
+            // 3. 이메일 확인
+            String email = kakaoProfile.kakao_account().email();
+            System.out.println("이메일 확인: " + email);
+            if (email == null) {
+                throw new MemberException(MemberErrorCode.OAUTH_EMAIL_NOT_FOUND);
+            }
+
+            // 4. 데이터베이스에서 사용자 조회 또는 신규 사용자 저장
+            System.out.println("사용자 조회 또는 저장 중...");
+            Member member = memberRepository.findByEmail(email)
+                    .orElseGet(() -> memberRepository.save(
+                            Member.builder()
+                                    .email(email)
+                                    .build()));
+
+            // 5. JWT 토큰 발급
+            System.out.println("JWT 토큰 발급 중...");
+            return JwtDTO.builder()
+                    .accessToken(jwtUtil.createAccessToken(member))
+                    .refreshToken(jwtUtil.createRefreshToken(member))
+                    .build();
+
+        } catch (Exception e) {
+            e.printStackTrace();
+            throw new MemberException(MemberErrorCode.OAUTH_LOGIN_FAIL);
+        }
+    }
+
+    private OAuth2DTO.OAuth2TokenDTO getAccessToken(String code) {
+        try {
+            MultiValueMap<String, String> formData = new LinkedMultiValueMap<>();
+            formData.add("grant_type", "authorization_code");
+            formData.add("client_id", clientId);
+            formData.add("redirect_uri", redirectURI);
+            formData.add("code", code);
+            formData.add("client_secret", clientSecret);
+
+            System.out.println("=== AccessToken 요청 정보 ===");
+            System.out.println("토큰 URI: " + tokenURI);
+            System.out.println("클라이언트 ID: " + clientId);
+            System.out.println("리다이렉트 URI: " + redirectURI);
+            System.out.println("인증 코드: " + code);
+
+            return webClient.post()
+                    .uri(tokenURI)
+                    .header(HttpHeaders.CONTENT_TYPE, "application/x-www-form-urlencoded")
+                    .bodyValue(formData)
+                    .retrieve()
+                    .onStatus(HttpStatusCode::isError, response -> {
+                        System.err.println("토큰 요청 오류: " + response.statusCode());
+                        return response.bodyToMono(String.class)
+                                .flatMap(errorBody -> {
+                                    System.err.println("오류 응답: " + errorBody);
+                                    return Mono.error(new RuntimeException("토큰 요청 실패: " + errorBody));
+                                });
+                    })
+                    .bodyToMono(OAuth2DTO.OAuth2TokenDTO.class)
+                    .doOnSuccess(token -> System.out.println("토큰 발급 성공: " + token.access_token()))
+                    .doOnError(e -> {
+                        System.err.println("토큰 요청 오류: " + e.getMessage());
+                        e.printStackTrace();
+                    })
+                    .onErrorMap(e -> new MemberException(MemberErrorCode.OAUTH_TOKEN_FAIL))
+                    .block();
+        } catch (Exception e) {
+            System.err.println("예외 발생: " + e.getMessage());
+            e.printStackTrace();
+            throw new MemberException(MemberErrorCode.OAUTH_TOKEN_FAIL);
+        }
+    }
+
+    private OAuth2DTO.KakaoProfile getUserInfo(String accessToken) {
+        return webClient.get()
+                .uri(userInfoURI)
+                .header(HttpHeaders.AUTHORIZATION, "Bearer " + accessToken)
+                .header(HttpHeaders.CONTENT_TYPE, "application/x-www-form-urlencoded;charset=utf-8")
+                .retrieve()
+                .bodyToMono(OAuth2DTO.KakaoProfile.class)
+                .onErrorMap(e -> new MemberException(MemberErrorCode.OAUTH_USER_INFO_FAIL)) // 에러 처리
+                .block();
+    }
+}

src/main/java/com/example/umc8th/global/config/SecurityConfig.java

@@ -9,6 +9,7 @@
 import lombok.RequiredArgsConstructor;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.Customizer;
 import org.springframework.security.config.annotation.web.builders.HttpSecurity;
 import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
 import org.springframework.security.config.http.SessionCreationPolicy;
@@ -29,13 +30,14 @@ public class SecurityConfig {
     private final JwtAuthenticationEntryPoint jwtAuthenticationEntryPoint;
     private final JwtAccessDeniedHandler jwtAccessDeniedHandler;
 
-    // 아래 3개는 Swagger에 대한 URL
     private String[] allowUrl = {
             "/auth/sign-up",
             "/auth/login",
             "/swagger-ui/**",
             "/swagger-resources/**",
             "/v3/api-docs/**",
+            "/oauth2/callback/kakao",
+            "/oauth2/authorization/kakao"
     };
 
     @Bean
@@ -45,8 +47,11 @@ SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
                         .requestMatchers(allowUrl).permitAll()
                         .anyRequest().authenticated()
                 )
+                .cors(cors -> cors.configurationSource(CorsConfig.apiConfigurationSource()))
                 .csrf(AbstractHttpConfigurer::disable)
                 .httpBasic(AbstractHttpConfigurer::disable)
+                .formLogin(AbstractHttpConfigurer::disable)
+                .oauth2Login(Customizer.withDefaults())
                 .addFilterBefore(jwtFilter(), UsernamePasswordAuthenticationFilter.class)
                 .exceptionHandling(exception -> exception
                         .authenticationEntryPoint(jwtAuthenticationEntryPoint)