feat: add get temporary password api

src/main/java/com/ourMenu/backend/domain/user/api/UserController.java

@@ -2,6 +2,8 @@
 
 import com.ourMenu.backend.domain.user.api.request.ChangeNicknameRequest;
 import com.ourMenu.backend.domain.user.api.request.ChangePasswordRequest;
+import com.ourMenu.backend.domain.user.api.request.TempPasswordRequest;
+import com.ourMenu.backend.domain.user.api.response.TempPasswordResponse;
 import com.ourMenu.backend.domain.user.api.response.UserArticleResponse;
 import com.ourMenu.backend.domain.user.api.response.UserInfoResponse;
 import com.ourMenu.backend.domain.user.application.UserService;
@@ -35,6 +37,15 @@ public ApiResponse<Object> changePassword(@UserId Long userId, @Valid @RequestBo
         return ApiUtils.success(null);
     }
 
+    @PostMapping("/password")
+    public ApiResponse<TempPasswordResponse> getTemporaryPassword(@Valid @RequestBody TempPasswordRequest request, BindingResult bindingResult) {
+        if(bindingResult.hasErrors()) {
+            throw new ValidationException(getErrorMessages(bindingResult));
+        }
+        String tempPwd = userService.getTemporaryPassword(request);
+        return ApiUtils.success(new TempPasswordResponse(tempPwd));
+    }
+
     @PatchMapping("/nickname")
     public ApiResponse<Object> changeNickname(@UserId Long userId, @Valid @RequestBody ChangeNicknameRequest request, BindingResult bindingResult) {
         if(bindingResult.hasErrors()) {

src/main/java/com/ourMenu/backend/domain/user/api/request/TempPasswordRequest.java

@@ -0,0 +1,16 @@
+package com.ourMenu.backend.domain.user.api.request;
+
+import jakarta.validation.constraints.Email;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class TempPasswordRequest {
+
+    @Email(message = "이메일 형식이 아닙니다")
+    private String email;
+
+}

src/main/java/com/ourMenu/backend/domain/user/api/response/TempPasswordResponse.java

@@ -0,0 +1,4 @@
+package com.ourMenu.backend.domain.user.api.response;
+
+public record TempPasswordResponse(String password) {
+}

src/main/java/com/ourMenu/backend/domain/user/application/UserService.java

@@ -2,6 +2,7 @@
 
 import com.ourMenu.backend.domain.user.api.request.ChangeNicknameRequest;
 import com.ourMenu.backend.domain.user.api.request.ChangePasswordRequest;
+import com.ourMenu.backend.domain.user.api.request.TempPasswordRequest;
 import com.ourMenu.backend.domain.user.api.response.UserArticleResponse;
 import com.ourMenu.backend.domain.user.api.response.UserInfoResponse;
 import com.ourMenu.backend.domain.user.dao.UserDao;
@@ -61,6 +62,28 @@ public void changePassword(Long userId, ChangePasswordRequest request) {
         userDao.updatePassword(userId, encodedNewPassword);
     }
 
+    public String getTemporaryPassword(TempPasswordRequest request) {
+        // get user by email
+        Map<String, Object> user = userDao.getUserByEmail(request.getEmail());
+        Long userId = (Long) user.get("user_id");
+
+        // make random password
+        String characters = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+        Random random = new Random();
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < 10; i++) {
+            int index = random.nextInt(characters.length());
+            sb.append(characters.charAt(index));
+        }
+        String tempPwd = sb.toString();
+
+        // update password
+        String encodedNewPassword = passwordEncoder.encode(tempPwd);
+        userDao.updatePassword(userId, encodedNewPassword);
+
+        return tempPwd;
+    }
+
     public void changeNickname(Long userId, ChangeNicknameRequest request) {
         userDao.updateNickname(userId, request.getNickname());
     }