SpringCloud 2.x学习笔记：16、Spring Cloud Gateway之限流(Greenwich版本）

偏执的太偏执、 2021-12-23 17:39 180阅读 0赞

## 1、令牌桶算法 ##

![在这里插入图片描述][20190626143545665.jpg]

## 2、简单例子 ##

### 2.1 pom ###

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <groupId>com.cntaiping.tpa</groupId>
        <artifactId>rate-limiter</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <packaging>jar</packaging>
        <name>rate-limiter</name>
        <description>Demo project for Spring Boot</description>
    
        <parent>
            <groupId>com.cntaiping.tpa</groupId>
            <artifactId>gateway</artifactId>
            <version>1.0-SNAPSHOT</version>
        </parent>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-webflux</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-gateway</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-redis-reactive</artifactId>
            </dependency>
    
        </dependencies>
    
    </project>

注意，下面两个依赖不能少，否则数据不能写入redis。

<dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-webflux</artifactId>
            </dependency>

### 2.2 application.properties ###

server:
      port: 8401
    spring:
      cloud:
        gateway:
          routes:
          - id: limit_route
            uri: http://httpbin.org:80/get
            predicates:
            - After=2017-01-20T17:42:47.789-07:00[America/Denver]
            filters:
            - name: RequestRateLimiter
              args:
                #用于限流的键的解析器的 Bean 对象的名字,使用 SpEL 表达式根据#{@beanName}获取Bean对象
                key-resolver: '#{@ipAddrKeyResolver}'
                #令牌桶填充速率
                redis-rate-limiter.replenishRate: 1
                #令牌桶总容量
                redis-rate-limiter.burstCapacity: 3
      application:
        name: rate-limiter
    
    ---
    spring:
      redis:
        host: 127.0.0.1
        port: 6379
        #password: 123456
        database: 0

### 2.3 限流类 ###

package com.cntaiping.tpa.ratelimiter;
    
    import org.springframework.cloud.gateway.filter.ratelimit.KeyResolver;
    import org.springframework.web.server.ServerWebExchange;
    import reactor.core.publisher.Mono;
    
    public class UriKeyResolver implements KeyResolver {
        @Override
        public Mono<String> resolve(ServerWebExchange exchange) {
            return Mono.just(exchange.getRequest().getURI().getPath());
        }
    }

package com.cntaiping.tpa.ratelimiter;
    
    import org.springframework.cloud.gateway.filter.ratelimit.KeyResolver;
    import org.springframework.web.server.ServerWebExchange;
    import reactor.core.publisher.Mono;
    
    public class IpAddrKeyResolver implements KeyResolver {
        @Override
        public Mono<String> resolve(ServerWebExchange exchange) {
            String ip=exchange.getRequest().getRemoteAddress().getAddress().getHostAddress();
            System.out.println("客户端IP="+ip);
            return Mono.just(ip);
        }
    }

### 2.4 Application类 ###

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.context.annotation.Bean;
    
    @SpringBootApplication
    public class RateLimiterApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(RateLimiterApplication.class, args);
        }
    
        @Bean
        public IpAddrKeyResolver ipAddrKeyResolver() {
            return new IpAddrKeyResolver();
        }
    }

### 2.5 运行效果 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70 1]

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70 2]

D:\Users\chengyq>redis-cli

![在这里插入图片描述][20190627104918641.png]

[20190626143545665.jpg]: /images/20211223/b59f70ee266d4d0dae4855bb0643355a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70]: /images/20211223/186d5c6405e4496284a0cdf29e65352c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70 1]: /images/20211223/245da84ae0d949e68eeed43ebae5f7a0.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5neXVxaWFuZw_size_16_color_FFFFFF_t_70 2]: /images/20211223/5fd8439660274907a01b33a436a2333a.png
[20190627104918641.png]: /images/20211223/4d64083ac43e457e9047e1aad7eaf247.png