gateway实现限流

1、添加依赖（springboot 2.3.9）可以不加这个依赖

<!--基于Redis实现限流-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis-reactive</artifactId>
    <version>2.2.10.RELEASE</version>
</dependency>

2、创建限流的bean，bean对象放入启动类里

package com.bw2102a;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.gateway.filter.ratelimit.KeyResolver;
import org.springframework.context.annotation.Bean;
import reactor.core.publisher.Mono;

/**
 * @author 军哥
 * @version 1.0
 * @description: ServerShopGatewayApplication
 * @date 2023/8/14 11:27
 */

@SpringBootApplication
@Slf4j
public class ServerShopGatewayApplication {

    public static void main(String[] args) {
        SpringApplication.run(ServerShopGatewayApplication.class, args);
    }

    /**
     * @description 通过IP限流
     * @author 军哥
     * @date 2023/9/5 10:34
     * @version 1.0
     */
    @Bean(name = "remoteAddrKeyResolver")
    public KeyResolver remoteAddrKeyResolver() {
        //按请求ip限流
        return exchange -> {
            log.info("remoteAddrKeyResolver:" + exchange.getRequest().getRemoteAddress().getAddress().getHostAddress());

            return Mono.just(exchange.getRequest().getRemoteAddress().getAddress().getHostAddress());
        };
    }

    /**
     * 按IP来限流
     */
//    @Bean(name = "ipAddrKeyResolver")
//    public KeyResolver ipAddrKeyResolver() {
//        // //JDK8的新特性——Lambda表达式
//        return exchange -> Mono.just(exchange.getRequest().getRemoteAddress().getAddress().getHostAddress());
//    }


    /**
     * 按用户限流
     */
//    @Bean(name = "userKeyResolver")
//    KeyResolver userKeyResolver() {
//        return exchange -> Mono.just(exchange.getRequest().getHeaders().getFirst("token"));
//    }

    /**
     * 按URL限流,即以每秒内请求数按URL分组统计，超出限流的url请求都将返回429状态
     *
     * @return
     */
//    @Bean(name = "apiKeyResolver")
//    KeyResolver apiKeyResolver() {
//        return exchange -> Mono.just(exchange.getRequest().getPath().toString());
//    }

}

3、修改gateway配置文件

      # 路由
      routes:
        - id: server-shop-user  #路由id 唯一的
          uri: lb://server-shop-user  # 请求微服务资源  lb表示负载均衡   deptservice 微服务的名称
          predicates: # 断言 路由规则
            - Path=/user/**
          filters:
            - StripPrefix=1
            - name: RequestRateLimiter    #过滤器名称
              args:
                key-resolver: "#{@remoteAddrKeyResolver}"    #使用SpEL表达式根据#{@beanName}从 Spring 容器中获取 Bean 对象
                redis-rate-limiter.replenishRate: 20 # 令牌桶填充的速率 秒为单位
                redis-rate-limiter.burstCapacity: 20 # 令牌桶总容量
                redis-rate-limiter.requestedTokens: 1 # 每次请求获取的令牌数

4、进行测试

• 限流的表现

• 不限流的表现