Email 중복 확인 api

apps/user-service/src/main/java/com/gltkorea/icebang/domain/user/controller/UserController.java

@@ -0,0 +1,30 @@
+package com.gltkorea.icebang.domain.user.controller;
+
+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 com.gltkorea.icebang.common.dto.ApiResponse;
+import com.gltkorea.icebang.domain.user.dto.CheckEmailRequest;
+import com.gltkorea.icebang.domain.user.dto.CheckEmailResponse;
+import com.gltkorea.icebang.domain.user.service.UserService;
+
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequestMapping("/v0/users")
+@RequiredArgsConstructor
+public class UserController {
+  private final UserService userService;
+
+  @PostMapping("/check-email")
+  public ApiResponse<CheckEmailResponse> checkEmailAvailable(
+      @Valid @RequestBody CheckEmailRequest request) {
+    Boolean available = !userService.isExistEmail(request);
+    String message = available.equals(Boolean.TRUE) ? "사용 가능한 이메일입니다." : "이미 가입된 이메일입니다.";
+
+    return ApiResponse.success(CheckEmailResponse.builder().available(available).build(), message);
+  }
+}

apps/user-service/src/main/java/com/gltkorea/icebang/domain/user/dto/CheckEmailRequest.java

@@ -0,0 +1,14 @@
+package com.gltkorea.icebang.domain.user.dto;
+
+import jakarta.validation.constraints.Email;
+import jakarta.validation.constraints.NotBlank;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+@Data
+@AllArgsConstructor
+public class CheckEmailRequest {
+  @NotBlank(message = "이메일은 필수입니다")
+  @Email(message = "올바른 이메일 형식이 아닙니다")
+  private String email;
+}

apps/user-service/src/main/java/com/gltkorea/icebang/domain/user/dto/CheckEmailResponse.java

@@ -0,0 +1,10 @@
+package com.gltkorea.icebang.domain.user.dto;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Data
+@Builder
+public class CheckEmailResponse {
+  private Boolean available;
+}

apps/user-service/src/main/java/com/gltkorea/icebang/domain/user/service/UserService.java

@@ -1,16 +1,20 @@
 package com.gltkorea.icebang.domain.user.service;
 
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
 import com.gltkorea.icebang.domain.auth.dto.RegisterDto;
+import com.gltkorea.icebang.domain.user.dto.CheckEmailRequest;
 import com.gltkorea.icebang.entity.Users;
+import com.gltkorea.icebang.mapper.UserMapper;
 
+import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 
 @Service
 @RequiredArgsConstructor
 public class UserService {
-  //    private final UserMapper userMapper;
+  private final UserMapper userMapper;
 
   public void registerUser(RegisterDto registerDto) {
     Users user =
@@ -21,4 +25,9 @@ public void registerUser(RegisterDto registerDto) {
             .status("PENDING")
             .build();
   }
+
+  @Transactional(readOnly = true)
+  public Boolean isExistEmail(@Valid CheckEmailRequest request) {
+    return userMapper.existsByEmail(request.getEmail());
+  }
 }

apps/user-service/src/main/java/com/gltkorea/icebang/mapper/UserMapper.java

@@ -0,0 +1,11 @@
+package com.gltkorea.icebang.mapper;
+
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Param;
+import org.apache.ibatis.annotations.Select;
+
+@Mapper
+public interface UserMapper {
+  @Select("SELECT COUNT(1) > 0 FROM users WHERE email = #{email}")
+  boolean existsByEmail(@Param("email") String email);
+}