[feat] 장바구니에 현재까지 담은 음식 상품의 금액을 볼 수 있는 기능 추가

src/main/java/camp/woowak/lab/cart/domain/Cart.java

@@ -15,17 +15,27 @@
 
 @Getter
 public class Cart {
-	private String customerId;
-	private List<Menu> menuList;
+	private final String customerId;
+	private final List<Menu> menuList;
 
 	/**
 	 * 생성될 때 무조건 cart가 비어있도록 구현
 	 *
 	 * @param customerId 장바구니 소유주의 ID값입니다.
 	 */
 	public Cart(String customerId) {
+		this(customerId, new LinkedList<>());
+	}
+
+	/**
+	 * 해당 Domain을 사용하는 같은 패키지내의 클래스, 혹은 자식 클래스는 List를 커스텀할 수 있습니다.
+	 *
+	 * @param customerId 장바구니 소유주의 ID값입니다.
+	 * @param menuList   장바구니에 사용될 List입니다.
+	 */
+	protected Cart(String customerId, List<Menu> menuList) {
 		this.customerId = customerId;
-		this.menuList = new LinkedList<>();
+		this.menuList = menuList;
 	}
 
 	public void addMenu(Menu menu) {
@@ -36,6 +46,14 @@ public void addMenu(Menu menu) {
 		this.menuList.add(menu);
 	}
 
+	public long getTotalPrice() {
+		return this.menuList.stream()
+			.map(Menu::getPrice)
+			.mapToLong(Long::valueOf)
+			.boxed()
+			.reduce(0L, Long::sum);
+	}
+
 	private void validateStoreOpenTime(Store store) {
 		if (!store.isOpen()) {
 			StoreTime storeTime = store.getStoreTime();

src/main/java/camp/woowak/lab/cart/service/CartService.java

@@ -6,6 +6,7 @@
 import camp.woowak.lab.cart.exception.MenuNotFoundException;
 import camp.woowak.lab.cart.repository.CartRepository;
 import camp.woowak.lab.cart.service.command.AddCartCommand;
+import camp.woowak.lab.cart.service.command.CartTotalPriceCommand;
 import camp.woowak.lab.menu.domain.Menu;
 import camp.woowak.lab.menu.repository.MenuRepository;
 
@@ -34,6 +35,11 @@ public void addMenu(AddCartCommand command) {
 		cartRepository.save(customerCart);
 	}
 
+	public long getTotalPrice(CartTotalPriceCommand command) {
+		return getCart(command.customerId())
+			.getTotalPrice();
+	}
+
 	private Cart getCart(String customerId) {
 		return cartRepository.findByCustomerId(customerId)
 			.orElse(cartRepository.save(new Cart(customerId)));

src/main/java/camp/woowak/lab/cart/service/command/CartTotalPriceCommand.java

@@ -0,0 +1,6 @@
+package camp.woowak.lab.cart.service.command;
+
+public record CartTotalPriceCommand(
+	String customerId
+) {
+}

src/main/java/camp/woowak/lab/web/api/cart/CartApiController.java

@@ -1,16 +1,19 @@
 package camp.woowak.lab.web.api.cart;
 
+import org.springframework.web.bind.annotation.GetMapping;
 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 camp.woowak.lab.cart.service.CartService;
 import camp.woowak.lab.cart.service.command.AddCartCommand;
+import camp.woowak.lab.cart.service.command.CartTotalPriceCommand;
 import camp.woowak.lab.web.authentication.LoginCustomer;
 import camp.woowak.lab.web.authentication.annotation.AuthenticationPrincipal;
 import camp.woowak.lab.web.dto.request.cart.AddCartRequest;
 import camp.woowak.lab.web.dto.response.cart.AddCartResponse;
+import camp.woowak.lab.web.dto.response.cart.CartTotalPriceResponse;
 import lombok.extern.slf4j.Slf4j;
 
 @RestController
@@ -33,4 +36,15 @@ public AddCartResponse addCart(
 		log.info("Customer({}) add Menu({}) in Cart", loginCustomer.getId(), addCartRequest.menuId());
 		return new AddCartResponse(true);
 	}
+
+	@GetMapping("/price")
+	public CartTotalPriceResponse getCartTotalPrice(
+		@AuthenticationPrincipal LoginCustomer loginCustomer
+	) {
+		CartTotalPriceCommand command = new CartTotalPriceCommand(loginCustomer.getId().toString());
+		long totalPrice = cartService.getTotalPrice(command);
+
+		log.info("Customer({})'s total price in cart is {}", loginCustomer.getId(), totalPrice);
+		return new CartTotalPriceResponse(totalPrice);
+	}
 }

src/main/java/camp/woowak/lab/web/dto/response/cart/CartTotalPriceResponse.java

@@ -0,0 +1,6 @@
+package camp.woowak.lab.web.dto.response.cart;
+
+public record CartTotalPriceResponse(
+	long totalPrice
+) {
+}

src/test/java/camp/woowak/lab/cart/domain/CartTest.java

@@ -0,0 +1,136 @@
+package camp.woowak.lab.cart.domain;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.time.LocalDateTime;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.UUID;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import camp.woowak.lab.cart.exception.OtherStoreMenuException;
+import camp.woowak.lab.cart.exception.StoreNotOpenException;
+import camp.woowak.lab.fixture.CartFixture;
+import camp.woowak.lab.menu.domain.Menu;
+import camp.woowak.lab.menu.domain.MenuCategory;
+import camp.woowak.lab.payaccount.domain.PayAccount;
+import camp.woowak.lab.store.domain.Store;
+import camp.woowak.lab.vendor.domain.Vendor;
+import camp.woowak.lab.web.authentication.NoOpPasswordEncoder;
+
+@DisplayName("Cart 클래스는")
+class CartTest implements CartFixture {
+	private final String customerId = UUID.randomUUID().toString();
+
+	private List<Menu> cartList;
+	private Cart cart;
+	private Menu menu;
+	private int minPrice = 8000;
+	private Store store;
+	private Vendor vendor;
+
+	@BeforeEach
+	void setUp() {
+		cartList = new LinkedList<>();
+		cart = new Cart(customerId, cartList);
+
+		vendor = createSavedVendor(UUID.randomUUID(), new PayAccount(), new NoOpPasswordEncoder());
+		store = createSavedStore(1L, vendor, "중화반점", minPrice,
+			LocalDateTime.now().minusMinutes(10).withSecond(0).withNano(0),
+			LocalDateTime.now().plusMinutes(10).withSecond(0).withNano(0));
+		menu = createSavedMenu(1L, store, new MenuCategory(store, "중식"), "짜장면", 9000);
+	}
+
+	@Nested
+	@DisplayName("addMenu 메서드")
+	class AddMenuTest {
+		@Test
+		@DisplayName("Menu를 받으면 cart에 저장된다.")
+		void addMenuTest() {
+			//given
+
+			//when
+			cart.addMenu(menu);
+
+			//then
+			assertThat(cartList.get(0)).isEqualTo(menu);
+		}
+
+		@Test
+		@DisplayName("열지 않은 가게의 메뉴를 담으면 StoreNotOpenException을 던진다.")
+		void storeNotOpenExceptionTest() {
+			//given
+			Store closedStore = createSavedStore(2L, vendor, "closed", minPrice,
+				LocalDateTime.now().minusMinutes(30).withSecond(0).withNano(0),
+				LocalDateTime.now().minusMinutes(10).withSecond(0).withNano(0));
+			Menu closedMenu = createSavedMenu(2L, closedStore, new MenuCategory(closedStore, "중식"), "짬뽕", 9000);
+
+			//when & then
+			assertThatThrownBy(() -> cart.addMenu(closedMenu))
+				.isExactlyInstanceOf(StoreNotOpenException.class);
+			assertThat(cartList).isEmpty();
+		}
+
+		@Test
+		@DisplayName("다른 가게의 메뉴를 함께 담으면 OtherStoreMenuException을 던진다.")
+		void otherStoreMenuExceptionTest() {
+			//given
+			cart.addMenu(menu);
+
+			Store otherStore = createSavedStore(2L, vendor, "closed", minPrice,
+				LocalDateTime.now().minusMinutes(30).withSecond(0).withNano(0),
+				LocalDateTime.now().plusMinutes(30).withSecond(0).withNano(0));
+			Menu otherStoreMenu = createSavedMenu(2L, otherStore, new MenuCategory(otherStore, "중식"), "짬뽕", 9000);
+
+			//when & then
+			assertThatThrownBy(() -> cart.addMenu(otherStoreMenu))
+				.isExactlyInstanceOf(OtherStoreMenuException.class);
+			assertThat(cartList).doesNotContain(otherStoreMenu);
+			assertThat(cartList).contains(menu);
+		}
+	}
+
+	@Nested
+	@DisplayName("totalPrice 메서드는")
+	class GetTotalPriceTest {
+		@Test
+		@DisplayName("장바구니가 비어있으면 0원을 return한다.")
+		void getTotalPriceWithEmptyList() {
+			//given
+
+			//when
+			long totalPrice = cart.getTotalPrice();
+
+			//then
+			assertThat(totalPrice).isEqualTo(0);
+		}
+
+		@Test
+		@DisplayName("현재 장바구니에 담긴 모든 메뉴의 총 금액을 return 받는다.")
+		void getTotalPriceTest() {
+			//given
+			MenuCategory menuCategory = new MenuCategory(store, "중식");
+			int price1 = 1000;
+			Menu menu1 = createSavedMenu(2L, store, menuCategory, "짜장면1", price1);
+			cart.addMenu(menu1);
+
+			int price2 = 2000;
+			Menu menu2 = createSavedMenu(3L, store, menuCategory, "짬뽕1", price2);
+			cart.addMenu(menu2);
+
+			int price3 = Integer.MAX_VALUE;
+			Menu menu3 = createSavedMenu(4L, store, menuCategory, "황제정식", price3);
+			cart.addMenu(menu3);
+
+			//when
+			long totalPrice = cart.getTotalPrice();
+
+			//then
+			assertThat(totalPrice).isEqualTo((long)price1 + (long)price2 + (long)price3);
+		}
+	}
+}

src/test/java/camp/woowak/lab/cart/service/CartServiceTest.java

@@ -18,6 +18,7 @@
 import camp.woowak.lab.cart.exception.StoreNotOpenException;
 import camp.woowak.lab.cart.repository.CartRepository;
 import camp.woowak.lab.cart.service.command.AddCartCommand;
+import camp.woowak.lab.cart.service.command.CartTotalPriceCommand;
 import camp.woowak.lab.customer.domain.Customer;
 import camp.woowak.lab.customer.repository.CustomerRepository;
 import camp.woowak.lab.menu.domain.Menu;
@@ -66,6 +67,7 @@ class CartServiceTest {
 
 	private Customer customer;
 	private Menu menu;
+	private MenuCategory menuCategory;
 	private Store store;
 	private Vendor vendor;
 
@@ -77,7 +79,9 @@ void setUp() {
 
 		store = createStore(vendor, "중화반점", minOrderPrice, startTime, endTime);
 
-		menu = createMenu(store, "짜장면", 90000);
+		menuCategory = createMenuCategory(store, "중식");
+
+		menu = createMenu(store, menuCategory, "짜장면", 90000);
 	}
 
 	@Nested
@@ -118,7 +122,8 @@ void throwExceptionWhenAddMenuInCartWithClosedStoresMenu() {
 			LocalDateTime startTime = LocalDateTime.now().minusMinutes(10).withSecond(0).withNano(0);
 			LocalDateTime endTime = LocalDateTime.now().minusMinutes(1).withSecond(0).withNano(0);
 			Store closedStore = createStore(vendor, "오픈 전의 중화반점", 8000, startTime, endTime);
-			Menu menu = createMenu(closedStore, "닫힌 가게의 메뉴", 1000);
+			MenuCategory closedMenuCategory = createMenuCategory(closedStore, "닫힌 카테고리");
+			Menu menu = createMenu(closedStore, closedMenuCategory, "닫힌 가게의 메뉴", 1000);
 
 			AddCartCommand command = new AddCartCommand(customer.getId().toString(), menu.getId());
 
@@ -132,7 +137,8 @@ void throwExceptionWhenAddMenuInCartWithClosedStoresMenu() {
 		void throwExceptionWhenAddMenuInCartWithOtherStoresMenu() {
 			//given
 			Store otherStore = createStore(vendor, "다른집", 8000, startTime, endTime);
-			Menu otherStoresMenu = createMenu(otherStore, "다른집 짜장면", 9000);
+			MenuCategory otherMenuCategory = createMenuCategory(otherStore, "다른집 카테고리");
+			Menu otherStoresMenu = createMenu(otherStore, otherMenuCategory, "다른집 짜장면", 9000);
 
 			AddCartCommand command1 = new AddCartCommand(customer.getId().toString(), menu.getId());
 			cartService.addMenu(command1);
@@ -144,10 +150,59 @@ void throwExceptionWhenAddMenuInCartWithOtherStoresMenu() {
 		}
 	}
 
-	private Menu createMenu(Store store, String name, int price) {
-		MenuCategory menuCategory = new MenuCategory(store, "카테고리1");
-		menuCategoryRepository.saveAndFlush(menuCategory);
-		Menu menu1 = new Menu(store, menuCategory,name, price,"imageUrl");
+	@Nested
+	@DisplayName("getTotalPrice 메서드")
+	class GetTotalPrice {
+		@Nested
+		@DisplayName("totalPrice 메서드는")
+		class GetTotalPriceTest {
+			@Test
+			@DisplayName("장바구니가 비어있으면 0원을 return한다.")
+			void getTotalPriceWithEmptyList() {
+				//given
+				CartTotalPriceCommand command = new CartTotalPriceCommand(customer.getId().toString());
+
+				//when
+				long totalPrice = cartService.getTotalPrice(command);
+
+				//then
+				assertThat(totalPrice).isEqualTo(0);
+			}
+
+			@Test
+			@DisplayName("현재 장바구니에 담긴 모든 메뉴의 총 금액을 return 받는다.")
+			void getTotalPriceTest() {
+				//given
+				int price1 = 1000;
+				Menu menu1 = createMenu(store, menuCategory, "짜장면1", price1);
+				cartService.addMenu(new AddCartCommand(customer.getId().toString(), menu1.getId()));
+
+				int price2 = 2000;
+				Menu menu2 = createMenu(store, menuCategory, "짬뽕1", price2);
+				cartService.addMenu(new AddCartCommand(customer.getId().toString(), menu2.getId()));
+
+				int price3 = Integer.MAX_VALUE;
+				Menu menu3 = createMenu(store, menuCategory, "황제정식", price3);
+				cartService.addMenu(new AddCartCommand(customer.getId().toString(), menu3.getId()));
+
+				CartTotalPriceCommand command = new CartTotalPriceCommand(customer.getId().toString());
+
+				//when
+				long totalPrice = cartService.getTotalPrice(command);
+
+				//then
+				assertThat(totalPrice).isEqualTo((long)price1 + (long)price2 + (long)price3);
+			}
+		}
+	}
+
+	private MenuCategory createMenuCategory(Store store, String name) {
+		MenuCategory menuCategory1 = new MenuCategory(store, name);
+		return menuCategoryRepository.saveAndFlush(menuCategory1);
+	}
+
+	private Menu createMenu(Store store, MenuCategory menuCategory, String name, int price) {
+		Menu menu1 = new Menu(store, menuCategory, name, price, "imageUrl");
 		menuRepository.saveAndFlush(menu1);
 
 		return menu1;

src/test/java/camp/woowak/lab/fixture/CartFixture.java

@@ -0,0 +1,31 @@
+package camp.woowak.lab.fixture;
+
+import java.time.LocalDateTime;
+import java.util.UUID;
+
+import camp.woowak.lab.menu.TestMenu;
+import camp.woowak.lab.menu.domain.Menu;
+import camp.woowak.lab.menu.domain.MenuCategory;
+import camp.woowak.lab.payaccount.domain.PayAccount;
+import camp.woowak.lab.store.TestStore;
+import camp.woowak.lab.store.domain.Store;
+import camp.woowak.lab.vendor.TestVendor;
+import camp.woowak.lab.vendor.domain.Vendor;
+import camp.woowak.lab.web.authentication.PasswordEncoder;
+
+public interface CartFixture {
+	default Vendor createSavedVendor(UUID id, PayAccount payAccount, PasswordEncoder passwordEncoder) {
+		return new TestVendor(
+			id, "vendorName", "vendorEmail@example.com", "vendorPassword", "010-0000-0000", payAccount,
+			passwordEncoder);
+	}
+
+	default Store createSavedStore(Long id, Vendor vendor, String name, int minOrderPrice, LocalDateTime startTIme,
+								   LocalDateTime endTime) {
+		return new TestStore(id, vendor, name, "송파", "010-1234-5678", minOrderPrice, startTIme, endTime);
+	}
+
+	default Menu createSavedMenu(Long id, Store store, MenuCategory menuCategory, String name, int price) {
+		return new TestMenu(id, store, menuCategory, name, price);
+	}
+}