package com.artisan.order.config;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;
@Configuration
public class RestTemplateConfig {
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
}

package com.artisan.order.client;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
// name为注册在注册中心上的名称
@FeignClient(name="ARTISAN-PRODUCT")
public interface ProductClient {
    // ARTISAN-PRODUCT微服务接口的访问路径
    @GetMapping("/product/serverMsg")
    String getServerInfo();
}

package com.artisan.order.controller;
import com.artisan.order.client.ProductClient;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@Slf4j
@RequestMapping("/order")
public class FeginClientController {
    @Autowired
    private ProductClient productClient;
    @GetMapping("/getServerInfoByFeign")
    public String requestServer(){
        String msg = productClient.getServerInfo();
        log.info("msg from server : {}", msg);
        return msg;
    }
}

  /**
     * 根据productIdList 查询商品列表
     * 提供给Order微服务用
     * @param productIdList
     * @return
     */
    @PostMapping("/productListForOrder")
    private List<Product> getProductForOrder(@RequestBody  List<String> productIdList){
        return productService.getProductList(productIdList);
    }

@Test
    public void decreaseProductTest() {
        CartDTO cartDTO = new CartDTO();
        cartDTO.setProductId("3");
        cartDTO.setProductQuantity(2);
        productService.decreaseProduct(Arrays.asList(cartDTO));
    }

@Override
    public OrderDTO createOrder(OrderDTO orderDTO) {
        String orderId = KeyUtil.genUniqueKey();
        //  查询商品信息（调用商品微服务）
        List<String> productIdList = orderDTO.getOrderDetailList().stream()
                .map(OrderDetail::getProductId)
                .collect(Collectors.toList());
        List<Product> productList = productClient.getProductForOrder(productIdList);
        //   计算订单总价
        BigDecimal orderAmout = new BigDecimal(BigInteger.ZERO);
        for (OrderDetail orderDetail: orderDTO.getOrderDetailList()) {
            for (Product product: productList) {
                if (product.getProductId().equals(orderDetail.getProductId())) {
                    //单价*数量
                    orderAmout = product.getProductPrice()
                            .multiply(new BigDecimal(orderDetail.getProductQuantity()))
                            .add(orderAmout);
                    BeanUtils.copyProperties(product, orderDetail);
                    orderDetail.setOrderId(orderId);
                    orderDetail.setDetailId(KeyUtil.genUniqueKey());
                    //订单详情入库
                    orderDetailRepository.save(orderDetail);
                }
            }
        }
        // 扣减库存（调用商品微服务）
        List<CartDTO> cartDTOList = orderDTO.getOrderDetailList().stream()
                .map(e -> new CartDTO(e.getProductId(), e.getProductQuantity()))
                .collect(Collectors.toList());
        productClient.decreseProduct(cartDTOList);
        //订单入库
        Order order = new Order();
        orderDTO.setOrderId(orderId);
        // 复制属性
        BeanUtils.copyProperties(orderDTO, order);
        // 设置其他属性
        order.setOrderAmount(orderAmout);
        order.setOrderStatus(OrderStatusEnum.NEW.getCode());
        order.setPayStatus(PayStatusEnum.WAIT.getCode());
        orderRepository.save(order);
        return orderDTO;
    }