如何为 Spring RESTful Web 服务创建 Spring 拦截器

我有一些没有 web.xml 的 Spring RESTful (RestControllers) Web 服务，并且我正在使用 Spring boot 来启动这些服务。

我想为 Web 服务添加授权层，并希望在实际调用 Web 服务本身之前将所有 http 请求路由到一个前端控制器。 （我有一个代码来模拟授权层的会话行为，根据我与客户端的每个 httpRequest 一起发送的生成密钥来验证用户）。

是否有任何标准 Spring 解决方案可以将所有请求路由到过滤器/前端控制器？

提前致谢， 普拉内斯

编辑： 添加我的代码

控制器： `

@RestController
public class UserService {
    UserDAO userDAO = new UserDAO();

    @RequestMapping(value="/login", method = RequestMethod.POST)
    @LoginRequired
    public String login(@RequestParam(value="user_name") String userName, @RequestParam(value="password") String password, HttpServletRequest request){
        return userDAO.login(userName, password);
    }
}`

拦截器：

`

public class AuthenticationInterceptor implements HandlerInterceptor  {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
        throws Exception {
        System.out.println("In Interceptor");
        //return super.preHandle(request, response, handler);
        return true;
    }
    @Override
    public void postHandle( HttpServletRequest request, HttpServletResponse response,
            Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("---method executed---");
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response,
            Object handler, Exception ex) throws Exception {
        System.out.println("---Request Completed---");
    }
}

`

界面。 `

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface LoginRequired {
}

`

使用 Spring 实现拦截器可以采取以下步骤：

• 实现一个扩展 HandlerInterceptorAdapter 类的拦截器类。代码如下所示：

  public class LoginInterceptor extends HandlerInterceptorAdapter {
  
      @Override
      public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception exception)
      throws Exception {
      // TODO Auto-generated method stub
  
      }
  
      @Override
      public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView)
      throws Exception {
      // TODO Auto-generated method stub
  
      }
  
      @Override
      public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
  
          HandlerMethod handlerMethod = (HandlerMethod) handler;
  
          String emailAddress = request.getParameter("emailaddress");
          String password = request.getParameter("password");
  
          if(StringUtils.isEmpty(emailAddress) || StringUtils.containsWhitespace(emailAddress) ||
          StringUtils.isEmpty(password) || StringUtils.containsWhitespace(password)) {
              throw new Exception("Invalid User Id or Password. Please try again.");
          }
  
          return true;
      }
  
  
  }
  

• 实现 AppConfig 类或在现有 Configuration 类之一中添加 addInterceptors。注意 LoginInterceptor 实例指定的路径模式

  @Configuration  
  public class AppConfig extends WebMvcConfigurerAdapter  {  
  
      @Override
      public void addInterceptors(InterceptorRegistry registry) {
         registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/account/login");
      }
  } 
  

• 实现控制器方法如下：

  @Controller
  @RequestMapping("/account/login")
  public class LoginController {
  
      @RequestMapping(method = RequestMethod.GET)
      public String login() {
          return "login";
      }
  }