[feat] 닉네임 중복검사 API

src/main/java/site/billbill/apiserver/api/auth/controller/AuthController.java

@@ -11,8 +11,10 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 import site.billbill.apiserver.api.auth.dto.request.*;
+import site.billbill.apiserver.api.auth.dto.response.NicknameResponse;
 import site.billbill.apiserver.api.auth.service.AuthService;
 import site.billbill.apiserver.api.auth.service.OAuthService;
+import site.billbill.apiserver.api.users.service.UserService;
 import site.billbill.apiserver.common.response.BaseResponse;
 import site.billbill.apiserver.common.utils.jwt.dto.JwtDto;
 
@@ -30,6 +32,7 @@ public class AuthController {
 
     private final AuthService authService;
     private final OAuthService oAuthService;
+    private final UserService userService;
 
     @Operation(summary = "회원 가입(일반)", description = "일반 회원 가입 API")
     @ResponseStatus(HttpStatus.CREATED)
@@ -64,4 +67,14 @@ public BaseResponse<JwtDto> kakaoCallback(@RequestParam("code") String code) {
     public BaseResponse<JwtDto> identity(@RequestBody IdentityVerificationRequest request) {
         return null;
     }
+
+    @Operation(summary = "닉네임 중복검사", description = "닉네임 중복검사")
+    @ResponseStatus(HttpStatus.OK)
+    @GetMapping("/nickname")
+    public BaseResponse<NicknameResponse> getNicknameValidity(@RequestParam String nickname) {
+        return new BaseResponse<>(NicknameResponse.builder()
+                .valid(authService.getNicknameValidity(nickname))
+                .build());
+    }
+
 }

src/main/java/site/billbill/apiserver/api/auth/dto/response/NicknameResponse.java

@@ -0,0 +1,10 @@
+package site.billbill.apiserver.api.auth.dto.response;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Data
+@Builder
+public class NicknameResponse {
+    private boolean valid;
+}

src/main/java/site/billbill/apiserver/api/auth/service/AuthService.java

@@ -13,4 +13,6 @@ public interface AuthService {
     JwtDto reissue(String refreshToken);
 
     boolean identifyUser(IdentityRequest request);
+
+    boolean getNicknameValidity(String nickname);
 }

src/main/java/site/billbill/apiserver/api/auth/service/AuthServiceImpl.java

@@ -118,6 +118,11 @@ public boolean identifyUser(IdentityRequest request) {
         return false;
     }
 
+    @Override
+    public boolean getNicknameValidity(String nickname) {
+        return !userRepository.existsByNickname(nickname);
+    }
+
     /**
      * Method that if user is withdrawn
      *

src/main/java/site/billbill/apiserver/repository/user/UserRepository.java

@@ -10,4 +10,5 @@
 public interface UserRepository extends JpaRepository<UserJpaEntity, String>, UserDslRepository {
     Optional<UserJpaEntity> findByUserIdAndWithdrawStatus(String userId, boolean withdrawStatus);
     Optional<UserJpaEntity> findByProviderId(String providerId);
+    boolean existsByNickname(String nickname);
 }