Gateway（4）：全局过滤器GlobalFilter

全局过滤器作用：对所有路由都生效，并且可以自定义处理逻辑

1、新建AuthorizeFilter类，实现GlobalFilter接口

import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.util.MultiValueMap;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;


//@Order(-1) //过滤器，执行顺序，值越小优先级越高
@Component
public class AuthorizeFilter implements GlobalFilter, Ordered {

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        //获取请求参数
        ServerHttpRequest request = exchange.getRequest();

        MultiValueMap<String, String> params = request.getQueryParams();

        //获取authorization
        String auth = params.getFirst("authorization");

        //判断是否等于admin
        //是 放行
        if ("admin" .equals(auth)) {
            return chain.filter(exchange);
        }
        //不是 ,设置状态码，拦截
        exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
        return exchange.getResponse().setComplete();
    }

    @Override
    public int getOrder() {
        return -1;
    }
}

2、指定顺序

@Order(-1)
实现Ordered接口，重新getOrder方法