[FEAT] 한달 지출률 조회 API 구현

src/main/java/umc/haruchi/converter/MonthBudgetConverter.java

@@ -33,4 +33,10 @@ public static MonthBudgetResponseDTO.GetMonthResultDTO toGetMonthResultDTO(Month
                 .createdAt(monthBudget.getCreatedAt())
                 .build();
     }
-}
+
+    public static MonthBudgetResponseDTO.GetMonthUsedPercentResultDTO toGetMonthUsedPercentResultDTO(double percent) {
+        return MonthBudgetResponseDTO.GetMonthUsedPercentResultDTO.builder()
+                .monthUsedPercent(percent)
+                .build();
+    }
+}

src/main/java/umc/haruchi/service/MonthBudgetService.java

@@ -128,6 +128,23 @@ public MonthBudget getMonthBudget(Long memberId) {
         return monthBudget;
     }
 
+    public double getMonthUsedPercent(Long memberId) {
+        LocalDate today = LocalDate.now();
+
+        //member가 존재하는 지 확인
+        Member member = memberRepository.findById(memberId)
+                .orElseThrow(() -> new MonthBudgetHandler(ErrorStatus.NO_MEMBER_EXIST));
+
+        //member와 year, month 기반으로 해당하는 monthBudget 찾기
+        MonthBudget monthBudget = monthBudgetRepository.findByMemberIdAndYearAndMonth(memberId, today.getYear(), today.getMonthValue())
+                .orElseThrow(() -> new MonthBudgetHandler(ErrorStatus.MONTH_BUDGET_NOT_FOUND));
+
+        //한달 지출률 계산
+        double monthUsedAmountPercent = ((double)monthBudget.getUsedAmount() / (double)monthBudget.getMonthBudget())*100;
+
+        //소수점 6번째자리에서 반올림해서 리턴
+        return Math.round(monthUsedAmountPercent*1000000)/1000000.0;
+    }
     private long roundDownToNearestHundred(long amount) {
         return (amount / 100) * 100;
     }

src/main/java/umc/haruchi/web/controller/MonthBudgetController.java

@@ -36,4 +36,12 @@ public ApiResponse<MonthBudgetResponseDTO.GetMonthResultDTO> getMonthBudget(@Aut
         MonthBudget monthBudget = monthBudgetService.getMonthBudget(memberDetail.getMember().getId());
         return ApiResponse.onSuccess(MonthBudgetConverter.toGetMonthResultDTO(monthBudget));
     }
+
+    //한달 지출률 조회
+    @Operation(summary =  "한달 지출률 조회 API", description = "본인의 한달 지출률을 조회하는 API")
+    @GetMapping("/percent")
+    public ApiResponse<MonthBudgetResponseDTO.GetMonthUsedPercentResultDTO> getMonthBudgetPercent(@AuthenticationPrincipal MemberDetail memberDetail) {
+        double monthBudgetPercent = monthBudgetService.getMonthUsedPercent(memberDetail.getMember().getId());
+        return ApiResponse.onSuccess(MonthBudgetConverter.toGetMonthUsedPercentResultDTO(monthBudgetPercent));
+    }
 }

src/main/java/umc/haruchi/web/dto/MonthBudgetResponseDTO.java

@@ -36,4 +36,12 @@ public static class GetMonthResultDTO {
         Long usedAmount;
         LocalDateTime createdAt;
     }
+
+    @Builder
+    @Getter
+    @NoArgsConstructor
+    @AllArgsConstructor
+    public static class GetMonthUsedPercentResultDTO {
+        double monthUsedPercent;
+    }
 }