网关----GateWay

概述

三大核心概念

Route(路由)

路由是构建网关的基本模块,它由ID,目标URI,一系列的断言和过滤器组成,如断言为true则匹配该路由

Predicate(断言)

参考的是Java8的java.util.function.Predicate
开发人员可以匹配HTTP请求中的所有内容(例如请求头或请求参数),如果请求与断言相匹配则进行路由

Filter(过滤)

指的是Spring框架中GatewayFilter的实例,使用过滤器,可以在请求被路由前或者之后对请求进行修改.

cloud-gateway-gateway9527服务的搭建

对外暴露9527这个端口

pom.xml

   <!--gateway-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
        <!--eureka-client-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

主启动类

package com.czf.springcloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableEurekaClient
public class GetWayMain9527 {
    public static void main(String[] args) {
        SpringApplication.run(GetWayMain9527.class,args);
    }
}

application.yml

server:
  port: 9527

spring:
  application:
    name: cloud-gateway
  cloud:
    gateway:
      discovery:
        locator:
          enabled: true #开启从注册中心动态创建路由的功能，利用微服务名进行路由
      routes:
        - id: payment_routh #payment_route    #路由的ID，没有固定规则但要求唯一，建议配合服务名
          #uri: http://localhost:8001          #匹配后提供服务的路由地址
          uri: lb://cloud-payment-service #匹配后提供服务的路由地址
          predicates:
            - Path=/payment/get/**         # 断言，路径相匹配的进行路由

        - id: payment_routh2 #payment_route    #路由的ID，没有固定规则但要求唯一，建议配合服务名
          #uri: http://localhost:8001          #匹配后提供服务的路由地址
          uri: lb://cloud-payment-service #匹配后提供服务的路由地址,lb是负载均衡的意思
          predicates:
            - Path=/payment/lb/**         # 断言，路径相匹配的进行路由
            #- After=2020-02-21T15:51:37.485+08:00[Asia/Shanghai]
            #- Cookie=username,zzyy
            #- Header=X-Request-Id, \d+  # 请求头要有X-Request-Id属性并且值为整数的正则表达式

eureka:
  instance:
    hostname: cloud-gateway-service
  client: #服务提供者provider注册进eureka服务列表内
    service-url:
      register-with-eureka: true
      fetch-registry: true
      defaultZone: http://eureka7001.com:7001/eureka

Gateway网关路由有两种配置方式

1.yml配置如上图所示
2.代码中注入RouteLocator的Bean

package com.czf.springcloud.config;

import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class GetWayConfig {
    @Bean
    public RouteLocator customRouteLocator(RouteLocatorBuilder routeLocatorBuilder){
        RouteLocatorBuilder.Builder routes = routeLocatorBuilder.routes();
        routes.route("path_route_czf",
                r->r.path("/guonei")//将localhost:9527/guonei映射成下面的url地址
                        .uri("http://news.baidu.com/guonei")).build();
        return routes.build();
    }
}

Filter

添加过滤器配置，必须有用户名才行，否则不通过

package com.czf.springcloud.filter;

import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.util.Date;

@Component
@Slf4j
public class MyLogGetWayFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        log.info("******come in MyLogGetWayFilter: "+new Date());
        String uname = exchange.getRequest().getQueryParams().getFirst("uname");
        if (uname == null){
            log.info("*****用户名为null,非法用户，(┬＿┬)");
            exchange.getResponse().setStatusCode(HttpStatus.NOT_ACCEPTABLE);
            return exchange.getResponse().setComplete();
        }
        return chain.filter(exchange);//通过进入下一个过滤连
    }

    @Override
    public int getOrder() {
        return 0;
    }
}