[feat] 프론트를 위한 API 추가

Co-authored-by: june-777 <[email protected]>

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

@@ -53,8 +53,8 @@ public long getTotalPrice(CartTotalPriceCommand command) {
 		return totalPrice;
 	}
 
-	private Cart getCart(String customerId) {
+	public Cart getCart(String customerId) {
 		return cartRepository.findByCustomerId(customerId)
-			.orElse(cartRepository.save(new Cart(customerId)));
+			.orElseGet(() -> cartRepository.save(new Cart(customerId)));
 	}
 }

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

@@ -6,13 +6,16 @@
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import camp.woowak.lab.cart.domain.Cart;
+import camp.woowak.lab.cart.domain.vo.CartItem;
 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.CartResponse;
 import camp.woowak.lab.web.dto.response.cart.CartTotalPriceResponse;
 import lombok.extern.slf4j.Slf4j;
 
@@ -26,6 +29,14 @@ public CartApiController(CartService cartService) {
 		this.cartService = cartService;
 	}
 
+	@GetMapping
+	public CartResponse getCart(@AuthenticationPrincipal LoginCustomer customer) {
+		Cart cart = cartService.getCart(customer.getId().toString());
+		long totalPrice = cartService.getTotalPrice(new CartTotalPriceCommand(customer.getId().toString()));
+		return new CartResponse(cart.getCustomerId(), cart.getCartItems().stream().mapToLong(CartItem::getAmount).sum(),
+			totalPrice);
+	}
+
 	@PostMapping
 	public AddCartResponse addCart(
 		@AuthenticationPrincipal LoginCustomer loginCustomer,
@@ -47,4 +58,5 @@ public CartTotalPriceResponse getCartTotalPrice(
 		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/CartResponse.java

@@ -0,0 +1,4 @@
+package camp.woowak.lab.web.dto.response.cart;
+
+public record CartResponse(String customerId, Long totalAmount, Long totalPrice) {
+}