获取Token来验证权限

首先需要了解过滤器和拦截器的区别以及运行顺序

图片来自@程序员内点事

有些时候需要在过滤中写跨域请求的处理

这里Token的验证就在拦截器里 当然写在过滤器里也行

import lombok.extern.slf4j.Slf4j;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;



@Configuration
public class MyConfig {
    @Order
    @Component
    @Slf4j
    public class AuthFilter implements Filter {

        String errorInterface = "/LoginController/request";//兜底方法
        //白名单接口
        private static List< String > whiteList = Arrays.asList(
                "/LoginController/login",
                "/LoginController/request"
        );

        //过滤器  这个过滤器用来处理跨域请求  验证token
        @Override
        public void doFilter(ServletRequest request,
                             ServletResponse response,
                             FilterChain chain) throws IOException, ServletException {

            //接口转换
            HttpServletRequest req = (HttpServletRequest) request;

            //白名单接口放行的操作(即不需要验证Token)
            String path = req.getServletPath()
            for (String s : whiteList) {
                if (path.contains(s)) {
                    chain.doFilter(request, response);
                    return;
                }
            }

            //中间写逻辑代码，判断Token是否正确，失败则返回false
            String token = req.getHeader("Token"); //从请求头中得到token
            if (token == null || token.trim().length() == 0) {
                //没有Token直接转发到错误请求
                request.getRequestDispatcher(errorInterface).forward(request, response);
                return;
            } else {
                chain.doFilter(request, response);
                return;
            }
        }
    }
}