#1099 Move add cart item API to cart module

cart/src/main/java/com/yas/cart/controller/CartItemV2Controller.java

@@ -0,0 +1,23 @@
+package com.yas.cart.controller;
+
+import com.yas.cart.service.CartItemV2Service;
+import com.yas.cart.viewmodel.CartItemV2GetVm;
+import com.yas.cart.viewmodel.CartItemV2PostVm;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequiredArgsConstructor
+public class CartItemV2Controller {
+    private final CartItemV2Service cartItemService;
+
+    @PostMapping("/storefront/cart/items")
+    public ResponseEntity<CartItemV2GetVm> addCartItem(@Valid @RequestBody CartItemV2PostVm cartItemPostVm) {
+        CartItemV2GetVm cartItemGetVm = cartItemService.addCartItem(cartItemPostVm);
+        return ResponseEntity.ok(cartItemGetVm);
+    }
+}

cart/src/main/java/com/yas/cart/mapper/CartItemV2Mapper.java

@@ -0,0 +1,36 @@
+package com.yas.cart.mapper;
+
+import com.yas.cart.model.CartItemV2;
+import com.yas.cart.viewmodel.CartItemV2GetVm;
+import com.yas.cart.viewmodel.CartItemV2PostVm;
+import org.springframework.stereotype.Component;
+
+@Component
+public class CartItemV2Mapper {
+    public CartItemV2GetVm toGetVm(CartItemV2 cartItem) {
+        return CartItemV2GetVm
+            .builder()
+            .customerId(cartItem.getCustomerId())
+            .productId(cartItem.getProductId())
+            .quantity(cartItem.getQuantity())
+            .build();
+    }
+
+    public CartItemV2 toCartItem(CartItemV2PostVm cartItemPostVm, String currentUserId) {
+        return CartItemV2
+            .builder()
+            .customerId(currentUserId)
+            .productId(cartItemPostVm.productId())
+            .quantity(cartItemPostVm.quantity())
+            .build();
+    }
+
+    public CartItemV2 toCartItem(String currentUserId, Long productId, int quantity) {
+        return CartItemV2
+            .builder()
+            .customerId(currentUserId)
+            .productId(productId)
+            .quantity(quantity)
+            .build();
+    }
+}

cart/src/main/java/com/yas/cart/model/AbstractAuditEntity.java

@@ -1,6 +1,7 @@
 package com.yas.cart.model;
 
 import com.yas.cart.listener.CustomAuditingEntityListener;
+import jakarta.persistence.Column;
 import jakarta.persistence.EntityListeners;
 import jakarta.persistence.MappedSuperclass;
 import java.time.ZonedDateTime;
@@ -17,9 +18,11 @@
 @EntityListeners(CustomAuditingEntityListener.class)
 public class AbstractAuditEntity {
     @CreationTimestamp
+    @Column(updatable = false)
     private ZonedDateTime createdOn;
 
     @CreatedBy
+    @Column(updatable = false)
     private String createdBy;
 
     @UpdateTimestamp

cart/src/main/java/com/yas/cart/model/CartItemV2.java

@@ -0,0 +1,25 @@
+package com.yas.cart.model;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.IdClass;
+import jakarta.persistence.Table;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "cart_item_v2")
+@IdClass(CartItemV2Id.class)
+@NoArgsConstructor
+@AllArgsConstructor
+@lombok.Getter
+@lombok.Setter
+@Builder
+public class CartItemV2 extends AbstractAuditEntity {
+    @Id
+    private String customerId;
+    @Id
+    private Long productId;
+    private int quantity;
+}

cart/src/main/java/com/yas/cart/model/CartItemV2Id.java

@@ -0,0 +1,15 @@
+package com.yas.cart.model;
+
+import lombok.AllArgsConstructor;
+import lombok.EqualsAndHashCode;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor
+@AllArgsConstructor
+@lombok.Getter
+@lombok.Setter
+@EqualsAndHashCode
+public class CartItemV2Id {
+    private String customerId;
+    private Long productId;
+}

cart/src/main/java/com/yas/cart/repository/CartItemV2Repository.java

@@ -0,0 +1,18 @@
+package com.yas.cart.repository;
+
+import com.yas.cart.model.CartItemV2;
+import com.yas.cart.model.CartItemV2Id;
+import jakarta.persistence.LockModeType;
+import jakarta.persistence.QueryHint;
+import java.util.Optional;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Lock;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.jpa.repository.QueryHints;
+
+public interface CartItemV2Repository extends JpaRepository<CartItemV2, CartItemV2Id> {
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @QueryHints({@QueryHint(name = "jakarta.persistence.lock.timeout", value = "0")})
+    @Query("SELECT c FROM CartItemV2 c WHERE c.customerId = :customerId AND c.productId = :productId")
+    Optional<CartItemV2> findWithLock(String customerId, Long productId);
+}

cart/src/main/java/com/yas/cart/service/CartItemV2Service.java

@@ -0,0 +1,62 @@
+package com.yas.cart.service;
+
+import com.yas.cart.mapper.CartItemV2Mapper;
+import com.yas.cart.model.CartItemV2;
+import com.yas.cart.repository.CartItemV2Repository;
+import com.yas.cart.utils.Constants;
+import com.yas.cart.viewmodel.CartItemV2GetVm;
+import com.yas.cart.viewmodel.CartItemV2PostVm;
+import com.yas.commonlibrary.exception.InternalServerErrorException;
+import com.yas.commonlibrary.exception.NotFoundException;
+import com.yas.commonlibrary.utils.AuthenticationUtils;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.dao.PessimisticLockingFailureException;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@RequiredArgsConstructor
+@Slf4j
+public class CartItemV2Service {
+    private final CartItemV2Repository cartItemRepository;
+    private final ProductService productService;
+    private final CartItemV2Mapper cartItemMapper;
+
+    @Transactional
+    public CartItemV2GetVm addCartItem(CartItemV2PostVm cartItemPostVm) {
+        validateProduct(cartItemPostVm.productId());
+
+        String currentUserId = AuthenticationUtils.extractUserId();
+        CartItemV2 cartItem = performAddCartItem(cartItemPostVm, currentUserId);
+
+        return cartItemMapper.toGetVm(cartItem);
+    }
+
+    private void validateProduct(Long productId) {
+        if (!productService.existsById(productId)) {
+            throw new NotFoundException(Constants.ErrorCode.NOT_FOUND_PRODUCT);
+        }
+    }
+
+    private CartItemV2 performAddCartItem(CartItemV2PostVm cartItemPostVm, String currentUserId) {
+        try {
+            return cartItemRepository.findWithLock(currentUserId, cartItemPostVm.productId())
+                .map(existingCartItem -> updateExistingCartItem(cartItemPostVm, existingCartItem))
+                .orElseGet(() -> createNewCartItem(cartItemPostVm, currentUserId));
+        } catch (PessimisticLockingFailureException e) {
+            log.error("Failed to acquire lock for adding cart item", e);
+            throw new InternalServerErrorException(Constants.ErrorCode.ADD_CART_ITEM_FAILED);
+        }
+    }
+
+    private CartItemV2 createNewCartItem(CartItemV2PostVm cartItemPostVm, String currentUserId) {
+        CartItemV2 cartItem = cartItemMapper.toCartItem(cartItemPostVm, currentUserId);
+        return cartItemRepository.save(cartItem);
+    }
+
+    private CartItemV2 updateExistingCartItem(CartItemV2PostVm cartItemPostVm, CartItemV2 existingCartItem) {
+        existingCartItem.setQuantity(existingCartItem.getQuantity() + cartItemPostVm.quantity());
+        return cartItemRepository.save(existingCartItem);
+    }
+}

cart/src/main/java/com/yas/cart/service/ProductService.java

@@ -7,6 +7,7 @@
 import java.net.URI;
 import java.util.List;
 import lombok.RequiredArgsConstructor;
+import org.apache.commons.collections4.CollectionUtils;
 import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestClient;
@@ -35,6 +36,18 @@ public List<ProductThumbnailVm> getProducts(List<Long> ids) {
             .getBody();
     }
 
+    public ProductThumbnailVm getProductById(Long id) {
+        List<ProductThumbnailVm> products = getProducts(List.of(id));
+        if (CollectionUtils.isEmpty(products)) {
+            return null;
+        }
+        return products.getFirst();
+    }
+
+    public boolean existsById(Long id) {
+        return getProductById(id) != null;
+    }
+
     protected List<ProductThumbnailVm> handleProductThumbnailFallback(Throwable throwable) throws Throwable {
         return handleTypedFallback(throwable);
     }

cart/src/main/java/com/yas/cart/utils/Constants.java

@@ -7,5 +7,6 @@ public static final class ErrorCode {
         public static final String NOT_EXISTING_ITEM_IN_CART = "NOT_EXISTING_ITEM_IN_CART";
         public static final String NOT_EXISTING_PRODUCT_IN_CART = "NOT_EXISTING_PRODUCT_IN_CART";
         public static final String NON_EXISTING_CART_ITEM = "NON_EXISTING_CART_ITEM";
+        public static final String ADD_CART_ITEM_FAILED = "ADD_CART_ITEM_FAILED";
     }
 }

cart/src/main/java/com/yas/cart/viewmodel/CartItemV2GetVm.java

@@ -0,0 +1,10 @@
+package com.yas.cart.viewmodel;
+
+import lombok.Builder;
+
+@Builder
+public record CartItemV2GetVm(
+    String customerId,
+    Long productId,
+    Integer quantity
+) {}

cart/src/main/java/com/yas/cart/viewmodel/CartItemV2PostVm.java

@@ -0,0 +1,10 @@
+package com.yas.cart.viewmodel;
+
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotNull;
+import lombok.Builder;
+
+@Builder
+public record CartItemV2PostVm(
+    @NotNull Long productId,
+    @NotNull @Min(1) Integer quantity) {}

cart/src/main/resources/db/changelog/ddl/changelog-0003.sql

@@ -0,0 +1,11 @@
+--changeset mochacr0:issue-1099-1
+CREATE TABLE cart_item_v2 (
+    customer_id VARCHAR(255) NOT NULL,
+    product_id BIGINT NOT NULL,
+    quantity INTEGER NOT NULL,
+    created_by VARCHAR(255),
+    created_on TIMESTAMP(6),
+    last_modified_by VARCHAR(255),
+    last_modified_on TIMESTAMP(6),
+    CONSTRAINT pk_cart_item PRIMARY KEY (customer_id, product_id)
+);

cart/src/main/resources/messages/messages.properties

@@ -5,3 +5,4 @@ NOT_FOUND_CART=Not found cart {}
 NOT_EXISTING_ITEM_IN_CART=There is no cart item in current cart to update!
 NOT_EXISTING_PRODUCT_IN_CART=There is no product with ID: {} in the current cart
 NON_EXISTING_CART_ITEM=Non exist cart item with ID: {}
+ADD_CART_ITEM_FAILED=Add cart item failed

cart/src/test/java/com/yas/cart/controller/CartItemV2ControllerTest.java

@@ -0,0 +1,107 @@
+package com.yas.cart.controller;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.yas.cart.service.CartItemV2Service;
+import com.yas.cart.viewmodel.CartItemV2GetVm;
+import com.yas.cart.viewmodel.CartItemV2PostVm;
+import com.yas.commonlibrary.exception.ApiExceptionHandler;
+import javax.ws.rs.core.MediaType;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.request.MockHttpServletRequestBuilder;
+
+@ExtendWith(SpringExtension.class)
+@WebMvcTest
+@ContextConfiguration(classes = {CartItemV2Controller.class, ApiExceptionHandler.class})
+@AutoConfigureMockMvc(addFilters = false)
+class CartItemV2ControllerTest {
+
+    private static final String CART_ITEM_BASE_URL = "/storefront/cart/items";
+    private static final String ADD_CART_ITEM_URL = CART_ITEM_BASE_URL;
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private ObjectMapper objectMapper;
+
+    @MockBean
+    private CartItemV2Service cartItemService;
+
+    @Nested
+    class AddToCartTest {
+
+        private CartItemV2PostVm.CartItemV2PostVmBuilder cartItemPostVmBuilder;
+
+        @BeforeEach
+        void setUp() {
+            cartItemPostVmBuilder = CartItemV2PostVm.builder()
+                .productId(1L)
+                .quantity(1);
+        }
+
+        @Test
+        void testAddToCart_whenProductIdIsNull_shouldReturnBadRequest() throws Exception {
+            CartItemV2PostVm cartItemPostVm = cartItemPostVmBuilder.productId(null).build();
+            performAddCartItemAndExpectBadRequest(cartItemPostVm);
+        }
+
+        @Test
+        void testAddToCart_whenQuantityIsNull_shouldReturnBadRequest() throws Exception {
+            CartItemV2PostVm cartItemPostVm = cartItemPostVmBuilder.quantity(null).build();
+            performAddCartItemAndExpectBadRequest(cartItemPostVm);
+        }
+
+        @Test
+        void testAddToCart_whenQuantityIsLessThanOne_shouldReturnBadRequest() throws Exception {
+            CartItemV2PostVm cartItemPostVm = cartItemPostVmBuilder.quantity(0).build();
+            performAddCartItemAndExpectBadRequest(cartItemPostVm);
+        }
+
+        @Test
+        void testAddToCart_whenRequestIsValid_shouldReturnCartItem() throws Exception {
+            CartItemV2PostVm cartItemPostVm = cartItemPostVmBuilder.build();
+            CartItemV2GetVm expectedCartItem = CartItemV2GetVm.builder()
+                .productId(cartItemPostVm.productId())
+                .quantity(cartItemPostVm.quantity())
+                .build();
+
+            when(cartItemService.addCartItem(cartItemPostVm)).thenReturn(expectedCartItem);
+
+            mockMvc.perform(buildAddCartItemRequest(cartItemPostVm))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.productId").value(expectedCartItem.productId()))
+                .andExpect(jsonPath("$.quantity").value(expectedCartItem.quantity()));
+
+            verify(cartItemService).addCartItem(cartItemPostVm);
+        }
+
+        private void performAddCartItemAndExpectBadRequest(CartItemV2PostVm cartItemPostVm)
+            throws Exception {
+            mockMvc.perform(buildAddCartItemRequest(cartItemPostVm))
+                .andExpect(status().isBadRequest());
+        }
+
+        private MockHttpServletRequestBuilder buildAddCartItemRequest(CartItemV2PostVm cartItemPostVm)
+            throws Exception {
+            return post(ADD_CART_ITEM_URL)
+                .contentType(MediaType.APPLICATION_JSON)
+                .content(objectMapper.writeValueAsString(cartItemPostVm));
+        }
+    }
+}