return rest + [[x] + y for y in rest if [x] + y not in rest]
时间: 2023-05-17 22:06:14 浏览: 58
这是一个 Python 代码片段,它使用列表推导式从 rest 列表中筛选出不包含 x 元素的所有元素 y,并将它们放入一个新的列表中返回。具体实现如下:
```
return [y for y in rest if x not in [y]]
```
这里使用了列表推导式和 in 运算符来实现筛选和判断操作。
相关问题
vue3 后端说是 接口使用 json Web Token +REST 前端接口应该如何配置
前端在使用 JSON Web Token(JWT)+ REST 接口时,需要在发送请求时在请求头中添加 JWT 的 Token。一般来说,可以在请求拦截器中进行配置。以下是一个示例代码:
```javascript
import axios from 'axios'
// 添加请求拦截器
axios.interceptors.request.use(
config => {
// 获取本地存储的 token
const token = localStorage.getItem('token')
// 在请求头中添加 Authorization 字段,并赋值为 token
if (token) {
config.headers.Authorization = `Bearer ${token}`
}
return config
},
error => {
return Promise.reject(error)
}
)
```
在上述代码中,我们通过请求拦截器获取本地存储的 Token,并将其添加到请求头的 Authorization 字段中。需要注意的是,JWT 的 Token 需要以 Bearer 开头,因此我们在添加时需要注意格式。
接下来,在发送请求时,我们只需要按照平常的方式调用 axios 即可,例如:
```javascript
axios.get('/api/user')
```
这样就会在请求头中添加 JWT 的 Token,从而进行身份验证。当然,在登录成功后,需要将服务器返回的 Token 存储到本地,以便在后续的请求中使用。
implement the shipping REST APIs with spring boot + sping mvc + jpa/batis + mysql + jwt
Sure, here's an outline of how you can implement the shipping REST APIs using Spring Boot, Spring MVC, JPA/Batis, MySQL, and JWT:
1. Set up a Spring Boot project with the necessary dependencies for Spring MVC, JPA/Batis, MySQL, and JWT. You can use Spring Initializr to generate the project structure and add the dependencies.
2. Define the domain model for the shipping application, including entities such as Order, Product, Customer, and ShippingAddress. Map the entities to database tables using JPA annotations or MyBatis mapper XML files.
3. Implement the repository layer to perform CRUD operations on the database using JPA or MyBatis. You can use Spring Data JPA or MyBatis-Spring to simplify the implementation.
4. Define the REST API endpoints for the shipping application using Spring MVC annotations. Use JWT for authentication and authorization of the API endpoints.
5. Implement the service layer to perform business logic operations such as calculating shipping costs, validating orders, and processing payments. Use dependency injection to inject the repository and other services into the service layer.
6. Write unit tests to ensure that the application logic is working correctly. You can use JUnit and Mockito to write the tests.
7. Deploy the application to a server and test the API endpoints using a tool such as Postman.
Here's some example code to get you started:
```java
@RestController
@RequestMapping("/api/orders")
public class OrderController {
@Autowired
private OrderService orderService;
@PostMapping("/")
public ResponseEntity<Order> createOrder(@RequestBody Order order) {
Order createdOrder = orderService.createOrder(order);
return ResponseEntity.ok(createdOrder);
}
@GetMapping("/{id}")
public ResponseEntity<Order> getOrder(@PathVariable("id") Long orderId) {
Order order = orderService.getOrder(orderId);
return ResponseEntity.ok(order);
}
// Other API endpoints for updating and deleting orders
}
@Service
public class OrderService {
@Autowired
private OrderRepository orderRepository;
public Order createOrder(Order order) {
// Calculate shipping costs and validate the order
order.setShippingCosts(10.0);
order.setTotalPrice(order.getProducts().stream()
.mapToDouble(Product::getPrice)
.sum() + order.getShippingCosts());
return orderRepository.save(order);
}
public Order getOrder(Long orderId) {
return orderRepository.findById(orderId)
.orElseThrow(() -> new NotFoundException("Order not found"));
}
// Other service methods for updating and deleting orders
}
@Repository
public interface OrderRepository extends JpaRepository<Order, Long> {
}
```
This code defines a REST API endpoint for creating orders and getting orders by ID. The order creation logic is implemented in the OrderService class, which calculates shipping costs and saves the order to the database using the OrderRepository interface. JWT authentication and authorization can be added to the API endpoints using Spring Security.