SpringBoot集成Redis主从架构实现读写分离（哨兵模式）

一、前言

这里会使用到spring-boot-starter-data-redis包，spring boot 2的spring-boot-starter-data-redis中，默认使用的是lettuce作为redis客户端，也推荐使用lettuce，Redis使用哨兵集群，这里会通过lettuce连接到哨兵获取对应Redis节点地址从而操作Redis。

Redis主从复制哨兵模式部署：https://blog.csdn.net/weixin_44606481/article/details/133990331

二、集成配置

工程结构

2.1、POM

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.12.RELEASE</version>
    </parent>
    
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!--springboot中的redis依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <!-- lettuce pool 缓存连接池-->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
        </dependency>
        <!-- 使用jackson作为redis数据序列化 -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.11.4</version>
        </dependency>
		<!-- SpringBoot测试包 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

2.2、添加配置文件application.yml

因为我们用的spring-boot-starter-data-redis包会自动配置redis连接，在配置文件中添加对应配置即可

spring:
  #redis配置信息
  redis:
    sentinel:
      # 主节点名称 在哨兵配置文件中配置的
      master: mymaster
      # 哨兵ip地址和端口 有多个哨兵就填多个，只填一个其实也能使用
      nodes:
        - 10.0.20.13:26379
        - 10.0.20.13:26380
        - 10.0.20.13:26381
    ## Redis数据库索引（默认为0）
    database: 0
    ## Redis服务连接密码（默认为空）
    password: 123456
    ## 连接超时时间（毫秒）
    timeout: 5000
    lettuce:
      pool:
        ## 连接池最大连接数（使用负值表示没有限制）
        max-active: 8
        ## 连接池最大阻塞等待时间（使用负值表示没有限制）
        max-wait: -1
        ## 连接池中的最大空闲连接
        max-idle: 8
        ## 连接池中的最小空闲连接
        min-idle: 1
      shutdown-timeout: 1000ms

# 打印lettuce debug日志，方便查看读写分离效果
logging:
  pattern:
    console: '%date{yyyy-MM-dd HH:mm:ss.SSS} | %highlight(%5level) [%green(%16.16thread)] %clr(%-50.50logger{49}){cyan} %4line -| %highlight(%msg%n)'
  level:
    root: info
    io.lettuce.core: debug
    org.springframework.data.redis: debug

2.3、编写配置文件

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.lettuce.core.ReadFrom;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.RedisSentinelConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.connection.lettuce.LettucePoolingClientConfiguration;
import org.springframework.data.redis.core.*;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

import java.util.HashSet;

@Configuration
public class RedisConfig{

    /**
     * 配置读写分离
     */
    @Bean
    public RedisConnectionFactory lettuceConnectionFactory(RedisProperties redisProperties) {
        // 配置哨兵节点以及主节点
        RedisSentinelConfiguration redisSentinelConfiguration = new RedisSentinelConfiguration(
                redisProperties.getSentinel().getMaster(), new HashSet<>(redisProperties.getSentinel().getNodes())
        );

        // 配置读写分离
        LettucePoolingClientConfiguration lettuceClientConfiguration = LettucePoolingClientConfiguration.builder()
                .poolConfig(getPoolConfig(redisProperties.getLettuce().getPool()))
                // ReadFrom.REPLICA_PREFERRED 优先读取从节点,如果从节点不可用,则读取主节点
                .readFrom(ReadFrom.REPLICA_PREFERRED)
                .build();

        return new LettuceConnectionFactory(redisSentinelConfiguration, lettuceClientConfiguration);
    }
    private GenericObjectPoolConfig<?> getPoolConfig(RedisProperties.Pool properties) {
        GenericObjectPoolConfig<?> config = new GenericObjectPoolConfig<>();
        config.setMaxTotal(properties.getMaxActive());
        config.setMaxIdle(properties.getMaxIdle());
        config.setMinIdle(properties.getMinIdle());
        if (properties.getTimeBetweenEvictionRuns() != null) {
            config.setTimeBetweenEvictionRunsMillis(properties.getTimeBetweenEvictionRuns().toMillis());
        }
        if (properties.getMaxWait() != null) {
            config.setMaxWaitMillis(properties.getMaxWait().toMillis());
        }
        return config;
    }

    /**
     * retemplate相关配置，配置自定义序列化规则为jackson
     */
    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        // 配置连接工厂
        template.setConnectionFactory(factory);
        //使用Jackson2JsonRedisSerializer来序列化和反序列化redis的value值（默认使用JDK的序列化方式）
        Jackson2JsonRedisSerializer jacksonSeial = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper om = new ObjectMapper();
        // 指定要序列化的域，field,get和set,以及修饰符范围，ANY是都有包括private和public
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        // 指定序列化输入的类型，类必须是非final修饰的，final修饰的类，比如String,Integer等会跑出异常
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jacksonSeial.setObjectMapper(om);
        // 值采用json序列化
        template.setValueSerializer(jacksonSeial);
        //使用StringRedisSerializer来序列化和反序列化redis的key值
        template.setKeySerializer(new StringRedisSerializer());
        // 设置hash key 和value序列化模式
        template.setHashKeySerializer(new StringRedisSerializer());
        template.setHashValueSerializer(jacksonSeial);
        template.afterPropertiesSet();
        return template;
    }
}

2.4、编写启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

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

2.5、编写测试类测试是否连接成功以及读写分离效果

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest(classes =  LettuceApplication.class)
public class LettuceTest {
    @Autowired
    private RedisTemplate<String,Object> redisTemplate;
    @Test
    public void t1(){
        String key = "key1";
        System.out.println("插入数据到redis");
        redisTemplate.opsForValue().set(key,"value1");
        Object value = redisTemplate.opsForValue().get(key);
        System.out.println("从redis中获取到值为 "+value);
        Boolean delete = redisTemplate.delete(key);
        System.out.println("删除redis中值 "+delete);
    }
}