feature: 카카오 로그인 추가

src/main/java/com/HHive/hhive/domain/user/controller/UserController.java

@@ -3,9 +3,11 @@
 import com.HHive.hhive.domain.user.UserDetailsImpl;
 import com.HHive.hhive.domain.user.dto.*;
 import com.HHive.hhive.domain.user.entity.User;
+import com.HHive.hhive.domain.user.service.KakaoService;
 import com.HHive.hhive.domain.user.service.UserService;
 import com.HHive.hhive.global.common.CommonResponse;
 import com.HHive.hhive.global.jwt.JwtUtil;
+import com.fasterxml.jackson.core.JsonProcessingException;
 import jakarta.servlet.http.Cookie;
 import jakarta.servlet.http.HttpServletResponse;
 import jakarta.validation.Valid;
@@ -21,15 +23,15 @@
 public class UserController {
 
     private final UserService userService;
-
     private final JwtUtil jwtUtil;
+    private final KakaoService kaKaoService;
 
     @PostMapping("/signup")
     public ResponseEntity<CommonResponse<Void>> signup(
             @Valid @RequestBody UserSignupRequestDTO requestDTO) {
 
         userService.signup(requestDTO);
-        return ResponseEntity.ok().body(CommonResponse.of(HttpStatus.CREATED.value(),"회원가입 성공", null));
+        return ResponseEntity.ok().body(CommonResponse.of(HttpStatus.CREATED.value(), "회원가입 성공", null));
     }
 
     @PostMapping("/login")
@@ -97,5 +99,19 @@ public ResponseEntity<CommonResponse<Void>> deleteUser(
 
     //TODO: 카테고리 선택
 
-    //TODO: 카카오 로그인
+    @GetMapping("/kakao/callback")
+    public String kakaoLogin(@RequestParam String code, HttpServletResponse response) throws JsonProcessingException {
+
+        // jwt 토큰 반환
+        String token = kaKaoService.kakaoLogin(code);
+
+        // 반환된 토큰을 쿠키에 넣음
+        Cookie cookie = new Cookie(jwtUtil.JWT_COOKIE_NAME, token);
+        cookie.setPath("/");
+
+        // + response 객체에 넣음
+        response.addCookie(cookie);
+
+        return "redirect:/";
+    }
 }

src/main/java/com/HHive/hhive/domain/user/dto/KakaoUserInfoDTO.java

@@ -0,0 +1,19 @@
+package com.HHive.hhive.domain.user.dto;
+
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor
+public class KakaoUserInfoDTO {
+
+    private Long id;
+    private String nickname;
+    private String email;
+
+    public KakaoUserInfoDTO(Long id, String nickname, String email) {
+        this.id = id;
+        this.nickname = nickname;
+        this.email = email;
+    }
+}

src/main/java/com/HHive/hhive/domain/user/service/KakaoService.java

@@ -0,0 +1,114 @@
+package com.HHive.hhive.domain.user.service;
+
+import com.HHive.hhive.domain.user.dto.KakaoUserInfoDTO;
+import com.HHive.hhive.domain.user.repository.UserRepository;
+import com.HHive.hhive.global.jwt.JwtUtil;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.RequestEntity;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Service;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import java.net.URI;
+
+@Slf4j(topic = "KAKAO Login")
+@Service
+@RequiredArgsConstructor
+public class KakaoService {
+
+    private final PasswordEncoder passwordEncoder;
+    private final UserRepository userRepository;
+    private final RestTemplate restTemplate;
+    private final JwtUtil jwtUtil;
+
+    public String kakaoLogin(String code) throws JsonProcessingException {
+
+        String accessToken = getToken(code);
+        KakaoUserInfoDTO kakaoUserInfoDTO = getKakaoUserInfo(accessToken);
+
+        return null;
+    }
+
+    // 액세스 토큰 요청
+    private String getToken(String code) throws JsonProcessingException {
+
+        log.info("인가코드 : " + code);
+
+        URI uri = UriComponentsBuilder
+                .fromUriString("https://kauth.kakao.com")
+                .path("/oauth/token")
+                .encode()
+                .build()
+                .toUri();
+
+        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", "${social.api.key.google}");
+        body.add("redirect_uri", "http://15.165.158.12/api/users/kakao/callback");
+        body.add("code", code);
+
+        RequestEntity<MultiValueMap<String, String>> requestEntity = RequestEntity
+                .post(uri)
+                .headers(headers)
+                .body(body);
+
+        // 카카오 서버로 HTTP 요청 보내기
+        ResponseEntity<String> response = restTemplate.exchange(
+                requestEntity,
+                String.class
+        );
+
+        // 액세스 토큰 파싱
+        JsonNode jsonNode = new ObjectMapper().readTree(response.getBody());
+        return jsonNode.get("access_token").asText();
+    }
+
+    // 사용자 정보 요청
+    private KakaoUserInfoDTO getKakaoUserInfo(String accessToken) throws JsonProcessingException {
+
+        log.info("acccessToken : " + accessToken);
+
+        URI uri = UriComponentsBuilder
+                .fromUriString("https://kauth.kakao.com")
+                .path("/oauth/token")
+                .encode()
+                .build()
+                .toUri();
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("Authorization", "Bearer%" + accessToken);
+        headers.add("Content-type", "application/x-www-form-urlencoded;charset=utf-8");
+
+        RequestEntity<MultiValueMap<String, String>> requestEntity = RequestEntity
+                .post(uri)
+                .headers(headers)
+                .body(new LinkedMultiValueMap<>());
+
+        ResponseEntity<String> response = restTemplate.exchange(
+                requestEntity,
+                String.class
+        );
+
+        JsonNode jsonNode = new ObjectMapper().readTree(response.getBody());
+        Long id = jsonNode.get("id").asLong();
+        String nickname = jsonNode.get("properties")
+                .get("nickname").asText();
+        String email = jsonNode.get("kakao_account")
+                .get("email").asText();
+
+        log.info("카카오 사용자 정보: " + id + ", " + nickname + ", " + email);
+        return new KakaoUserInfoDTO(id, nickname, email);
+    }
+}

src/main/java/com/HHive/hhive/global/config/RestTemplateConfig.java

@@ -0,0 +1,22 @@
+package com.HHive.hhive.global.config;
+
+import org.springframework.boot.web.client.RestTemplateBuilder;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.client.RestTemplate;
+
+import java.time.Duration;
+
+@Configuration
+public class RestTemplateConfig {
+
+    @Bean
+    public RestTemplate restTemplate(RestTemplateBuilder restTemplateBuilder) {
+
+        // 외부 API 호출 시 30초가 지나도 응답이 없을 때 강제 종료
+        return restTemplateBuilder
+                .setConnectTimeout(Duration.ofSeconds(30))
+                .setReadTimeout(Duration.ofSeconds(30))
+                .build();
+    }
+}

src/main/resources/application-local.yml

@@ -7,8 +7,18 @@ spring:
 
   jpa:
     hibernate:
-      ddl-auto: none
+      ddl-auto: update
     properties:
       hibernate:
         show_sql: true
-    open-in-view: false
+    open-in-view: false
+
+jwt:
+  secret:
+    key: ${JWT_SECRET_KEY}
+
+
+social:
+  api:
+    key:
+      kakao: ${KAKAO_API_KEY}

src/main/resources/application-prod.yml

@@ -15,4 +15,9 @@ spring:
 
 jwt:
   secret:
-    key: ${JWT_SECRET_KEY}
+    key: ${JWT_SECRET_KEY}
+
+social:
+  api:
+    key:
+      kakao: ${KAKAO_API_KEY}

src/main/resources/application-test.yml

@@ -20,4 +20,9 @@ spring:
 
 jwt:
   secret:
-    key: ${JWT_SECRET_KEY}
+    key: ${JWT_SECRET_KEY}
+
+social:
+  api:
+    key:
+      kakao: ${KAKAO_API_KEY}