Feat: 사용자 존재 여부 체크

src/main/java/com/hackathon/momento/member/api/MemberController.java

@@ -14,6 +14,7 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PatchMapping;
+import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.PutMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -78,4 +79,19 @@ public RspTemplate<ProfileResDto> updateProfile(
         ProfileResDto updatedProfile = memberService.updateProfile(principal, reqDto);
         return new RspTemplate<>(HttpStatus.OK, "프로필 수정 성공", updatedProfile);
     }
+
+    @PostMapping("/check-duplicate")
+    @Operation(
+            summary = "이메일 중복 검사",
+            description = "해당 사용자가 존재하는지 여부를 검사합니다.",
+            responses = {
+                    @ApiResponse(responseCode = "200", description = "중복 검사 성공"),
+                    @ApiResponse(responseCode = "400", description = "잘못된 요청"),
+                    @ApiResponse(responseCode = "500", description = "서버 오류")
+            }
+    )
+    public RspTemplate<String> checkDuplicateRequest(Principal principal) {
+        boolean isDuplicate = memberService.checkDuplicate(principal);
+        return new RspTemplate<>(HttpStatus.OK, String.valueOf(isDuplicate));
+    }
 }

src/main/java/com/hackathon/momento/member/application/MemberService.java

@@ -46,6 +46,11 @@ public ProfileResDto updateProfile(Principal principal, UpdateProfileReqDto reqD
         return ProfileResDto.from(member);
     }
 
+    public boolean checkDuplicate(Principal principal) {
+        Member member = getMemberByPrincipal(principal);
+        return memberRepository.existsById(member.getId());
+    }
+
     private Member getMemberByPrincipal(Principal principal) {
         Long memberId = Long.parseLong(principal.getName());
         return memberRepository.findById(memberId)

src/main/java/com/hackathon/momento/member/domain/repository/MemberRepository.java

@@ -8,5 +8,6 @@
 @Repository
 public interface MemberRepository extends JpaRepository<Member, Long> {
 
+
     Optional<Member> findByEmail(String email);
 }