Feat: 주문 정보 단일 조회(#16)

close: #16

src/main/java/com/hanaro/starbucks/controller/OrderController.java

@@ -4,6 +4,7 @@
 import com.hanaro.starbucks.service.OrderService;
 import lombok.RequiredArgsConstructor;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
@@ -19,6 +20,9 @@ public class OrderController {
     public List<OrderResDto> getOrders() {
         return orderService.getOrders();
     }
-
+    @GetMapping("/{orderIdx}")
+    public OrderResDto getOrder(@PathVariable int orderIdx) {
+        return orderService.getOrder(orderIdx);
+    }
 
 }

src/main/java/com/hanaro/starbucks/service/OrderService.java

@@ -9,6 +9,7 @@
 import org.springframework.stereotype.Service;
 
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 @Service
@@ -34,6 +35,21 @@ public List<OrderResDto> getOrders() {
         return orderResDtos;
     }
 
+    public OrderResDto getOrder(int orderIdx) {
+        Optional<Orders> optionalOrders = orderRepository.findById(orderIdx);
+        if(optionalOrders.isEmpty()){
+            throw new IllegalArgumentException("주문 내역이 존재하지 않습니다.");
+        }
+        Orders order = optionalOrders.get();
+        return OrderResDto.builder()
+                .orderIdx(order.getOrderIdx())
+                .orderId(order.getOrderId())
+                .totalPrice(calculateTotalPrice(order.getOrderDetails()))
+                .orderStatus(order.getOrderStatus())
+                .orderDate(order.getOrderDate())
+                .build();
+    }
+
     private int calculateTotalPrice(List<OrderDetail> orderDetails) {
         int totalPrice = 0;
         for (OrderDetail orderDetail : orderDetails) {