Feat: 카카오 로그인 구현

src/main/java/com/codiary/backend/global/config/SecurityConfig.java

@@ -58,6 +58,7 @@ public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Excepti
                                 .requestMatchers("/members/sign-up", "/members/sign-up/check-email", "/members/sign-up/check-nickname").permitAll()
                                 .requestMatchers("/members/login", "members/logout", "members/posts").permitAll()
                                 .requestMatchers("/members/**").permitAll()
+                                .requestMatchers("oauth/login/**").permitAll()
                                 // Post 관련 접근
                                 .requestMatchers("/posts","/posts/{postId}", "/posts/visibility/{postId}", "/posts/coauthors/{postId}", "/posts/categories/{postId}").permitAll()
                                 .requestMatchers("/posts/title/paging", "/posts/team/{teamId}/{postId}", "/posts/team/{teamId}/member/{memberId}/paging", "/posts/project/{projectId}/team/{teamId}/paging", "/posts/project/{projectId}/member/{memberId}/paging", "/posts/member/{memberId}/paging", "/posts/categories/paging", "/posts/{postId}/adjacent").permitAll()

src/main/java/com/codiary/backend/global/jwt/JwtTokenProvider.java

@@ -70,6 +70,35 @@ public TokenInfo generateToken(Authentication authentication, Long memberId) {
                 .build();
     }
 
+    // 이메일로 토큰 생성
+    public TokenInfo generateToken(String email, Long memberId) {
+        long now = (new Date()).getTime();
+
+        // Access Token 생성
+        Date accessTokenExpiresIn = new Date(now + ACCESS_TOKEN_EXPIRE_TIME);
+        String accessToken = Jwts.builder()
+                .setSubject(email)
+                .claim(AUTHORITIES_KEY, "ROLE_USER")
+                .claim("memberId", memberId)
+                .setExpiration(accessTokenExpiresIn)
+                .signWith(key, SignatureAlgorithm.HS256)
+                .compact();
+
+        // Refresh Token 생성
+        String refreshToken = Jwts.builder()
+                .setExpiration(new Date(now + REFRESH_TOKEN_EXPIRE_TIME))
+                .signWith(key, SignatureAlgorithm.HS256)
+                .compact();
+
+        // 생성된 토큰 정보를 반환
+        return TokenInfo.builder()
+                .grantType(BEARER_TYPE)
+                .accessToken(accessToken)
+                .refreshToken(refreshToken)
+                .build();
+    }
+
+
     // 토큰을 복호화하여 정보 추출
     public Authentication getAuthentication(String accessToken) {
         Claims claims = parseClaims(accessToken);

src/main/java/com/codiary/backend/global/service/MemberService/SocialLoginService.java

@@ -0,0 +1,142 @@
+package com.codiary.backend.global.service.MemberService;
+
+import com.codiary.backend.global.apiPayload.ApiResponse;
+import com.codiary.backend.global.apiPayload.code.status.SuccessStatus;
+import com.codiary.backend.global.domain.entity.Member;
+import com.codiary.backend.global.jwt.JwtTokenProvider;
+import com.codiary.backend.global.jwt.TokenInfo;
+import com.codiary.backend.global.repository.MemberRepository;
+import com.codiary.backend.global.web.dto.Member.MemberResponseDTO;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.RequiredArgsConstructor;
+import org.joda.time.LocalDate;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.stereotype.Service;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.RestTemplate;
+
+@Service
+@RequiredArgsConstructor
+public class SocialLoginService {
+
+    private final MemberRepository memberRepository;
+    private final JwtTokenProvider jwtTokenProvider;
+    private final AuthenticationManagerBuilder authenticationManagerBuilder;
+
+    @Value("${kakao.redirect.url}")
+    private String kakaoRedirectUrl;
+
+    @Value("${kakao.cliend.id}")
+    private String kakaoClientId;
+
+
+    public String getRedirectUrl() {
+        String path = "https://kauth.kakao.com/oauth/authorize?response_type=code";
+        String clientId = "&client_id=" + kakaoClientId;
+        String redirectUrl = "&redirect_uri=" + kakaoRedirectUrl;
+
+        return path + clientId + redirectUrl;
+    }
+
+    public ApiResponse<MemberResponseDTO.MemberTokenResponseDTO> kakaoLogin(String code) {
+
+        String kakaoAccessToken = getKakaoToken(code);
+        String userEmail = getKakaoUserEmail(kakaoAccessToken);
+
+        if (!memberRepository.existsByEmail(userEmail)) {
+            Member member = Member.builder()
+                    .email(userEmail)
+                    .password("")
+                    .nickname(userEmail)
+                    .birth(new LocalDate().toString())
+                    .gender(Member.Gender.Male)
+                    .github("")
+                    .linkedin("")
+                    .discord("")
+                    .image(null)
+                    .build();
+            memberRepository.save(member);
+        }
+        Member member = memberRepository.findByEmail(userEmail).get();
+
+
+        TokenInfo tokenInfo = jwtTokenProvider.generateToken(member.getEmail(), member.getMemberId());
+
+        return ApiResponse.of(SuccessStatus.MEMBER_OK, MemberResponseDTO.MemberTokenResponseDTO.builder()
+                .email(member.getEmail())
+                .nickname(member.getNickname())
+                .tokenInfo(tokenInfo)
+                .memberId(member.getMemberId())
+                .build());
+    }
+
+    private String getKakaoToken(String code) {
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("Content-Type", "application/x-www-form-urlencoded;charset=utf-8");
+
+        MultiValueMap<String, String> body = new LinkedMultiValueMap<>();
+        body.add("grant_type", "authorization_code");
+        body.add("client_id", kakaoClientId);
+        body.add("redirect_uri", kakaoRedirectUrl);
+        body.add("code", code);
+
+        HttpEntity<MultiValueMap<String, String>> kakaoTokenRequest = new HttpEntity<>(body, headers);
+        RestTemplate rt = new RestTemplate();
+        ResponseEntity<String> response = rt.exchange(
+                "https://kauth.kakao.com/oauth/token",
+                HttpMethod.POST,
+                kakaoTokenRequest,
+                String.class
+        );
+
+        String responseBody = response.getBody();
+        ObjectMapper objectMapper = new ObjectMapper();
+        JsonNode jsonNode;
+        try {
+            jsonNode = objectMapper.readTree(responseBody);
+        } catch (JsonProcessingException e) {
+            throw new RuntimeException(e);
+        }
+
+        return jsonNode.get("access_token").asText();
+    }
+
+
+    private String getKakaoUserEmail(String kakaoAccessToken) {
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("Authorization", "Bearer " + kakaoAccessToken);
+        headers.add("Content-type", "application/x-www-form-urlencoded;charset=utf-8");
+
+        HttpEntity<MultiValueMap<String, String>> kakaoUserInfoRequest = new HttpEntity<>(headers);
+        RestTemplate rt = new RestTemplate();
+        ResponseEntity<String> response = rt.exchange(
+                "https://kapi.kakao.com/v2/user/me",
+                HttpMethod.POST,
+                kakaoUserInfoRequest,
+                String.class
+        );
+
+        String responseBody = response.getBody();
+        ObjectMapper objectMapper = new ObjectMapper();
+        JsonNode jsonNode;
+        try {
+            jsonNode = objectMapper.readTree(responseBody);
+        } catch (JsonProcessingException e) {
+            throw new RuntimeException(e);
+        }
+
+        Long id = jsonNode.get("id").asLong();
+        String email = jsonNode.get("kakao_account").get("email").asText();
+
+        return email;
+    }
+}

src/main/java/com/codiary/backend/global/web/controller/SocialLoginController.java

@@ -0,0 +1,31 @@
+package com.codiary.backend.global.web.controller;
+
+import com.codiary.backend.global.apiPayload.ApiResponse;
+import com.codiary.backend.global.apiPayload.code.status.SuccessStatus;
+import com.codiary.backend.global.service.MemberService.SocialLoginService;
+import com.codiary.backend.global.web.dto.Member.MemberResponseDTO;
+import com.codiary.backend.global.web.dto.SocialLogin.Oauth2ResponseDTO;
+import io.swagger.v3.oas.annotations.Operation;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+@RequestMapping("/oauth")
+@RequiredArgsConstructor
+public class SocialLoginController {
+
+    private final SocialLoginService socialLoginService;
+
+    @PostMapping("/login/kakao")
+    @Operation(summary = "카카오 로그인")
+    public ApiResponse<Oauth2ResponseDTO.kakaoLoginDTO> kakaoLogin() {
+        String url = socialLoginService.getRedirectUrl();
+        return ApiResponse.onSuccess(SuccessStatus.MEMBER_OK, new Oauth2ResponseDTO.kakaoLoginDTO(url));
+    }
+
+    @GetMapping("/login/kakao")
+    @Operation(summary = "카카오 서버에서 요청하는 api")
+    public ApiResponse<MemberResponseDTO.MemberTokenResponseDTO> kekaoToken(@RequestParam String code) {
+        return socialLoginService.kakaoLogin(code);
+    }
+}

src/main/java/com/codiary/backend/global/web/dto/SocialLogin/Oauth2ResponseDTO.java

@@ -0,0 +1,15 @@
+package com.codiary.backend.global.web.dto.SocialLogin;
+
+import lombok.*;
+
+public class Oauth2ResponseDTO {
+
+    @Getter
+    @Setter
+    @Builder
+    @AllArgsConstructor
+    @NoArgsConstructor
+    public static class kakaoLoginDTO {
+        String redirectUrl;
+    }
+}