SpringBoot integrated Lettuce connection Redis method and case

First use maven to add the following dependencies in pom.xml

illustrate:

• SpringBoot uses the lettuce client to connect by default since 2.0.
• The version used this time: springboot: 2.6.6, lettuce: 6.1.8.

<dependency> 
  <groupId>org.springframework.boot</groupId>  
  <artifactId>spring-boot-starter-web</artifactId>  
</dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>  
  <artifactId>spring-boot-starter-data-redis</artifactId>  
</dependency>

 Use SpringBoot to integrate Lettuce connection instance

• Example of Springboot+Lettuce single-connection connection to Redis stand-alone/active/standby/Proxy cluster.

1. Add redis-related configuration to the application.properties configuration file. 

spring.redis.host=host  
spring.redis.database=0  
spring.redis.password=pwd 
spring.redis.port=port

2. Redis configuration class RedisConfiguration.

@Bean  
public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {   
    RedisTemplate<String, Object> template = new RedisTemplate<>();  
    template.setConnectionFactory(lettuceConnectionFactory);  
    //使用Jackson2JsonRedisSerializer替换默认的JdkSerializationRedisSerializer来序列化和反序列化redis的value值  
    Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);  
    ObjectMapper mapper = new ObjectMapper();  
    mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);  
    mapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance,  
        ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);  
    jackson2JsonRedisSerializer.setObjectMapper(mapper);  
    StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();  
    //key采用String的序列化方式  
    template.setKeySerializer(stringRedisSerializer);  
    // hash的key也采用String的序列化方式  
    template.setHashKeySerializer(stringRedisSerializer);  
    // value序列化方式采用jackson  
    template.setValueSerializer(jackson2JsonRedisSerializer);  
    // hash的value序列化方式采用jackson  
    template.setHashValueSerializer(jackson2JsonRedisSerializer);  
    template.afterPropertiesSet();  
    return template;  
}  

3. Redis operation class RedisUtil.

 /** 
  * 普通缓存获取 
  * @param key 键 
  * @return 值 
  */  
 public Object get(String key){  
     return key==null?null:redisTemplate.opsForValue().get(key);  
 }  

 /** 
  * 普通缓存放入 
  * @param key 键 
  * @param value 值 
  * @return true成功 false失败 
  */  
 public boolean set(String key,Object value) {  
     try {  
         redisTemplate.opsForValue().set(key, value);  
         return true;  
     } catch (Exception e) {  
         e.printStackTrace();  
         return false;  
     }  
 }

4. Write the controller class for testing.

@RestController  
public class HelloRedis {  
    @Autowired  
    RedisUtil redisUtil;  


    @RequestMapping("/setParams")  
    @ResponseBody  
    public String setParams(String name) {  
	    redisUtil.set("name", name);  
	    return "success";  
	}  
	
    @RequestMapping("/getParams")  
    @ResponseBody  
    public String getParams(String name) {  
	   System.out.println("--------------" + name + "-------------");  
	   String retName = redisUtil.get(name) + "";  
	   return retName;  
	}  
	
}  

• SpringBoot+Lettuce connection pool connection Redis stand-alone/active/standby/Proxy cluster example.

 1. Add the following dependencies based on the above maven dependencies.

<dependency>  
  <groupId>org.apache.commons</groupId>  
  <artifactId>commons-pool2</artifactId>  
</dependency> 

2. Add redis-related configuration to the application.properties configuration file.

spring.redis.host=host  
spring.redis.database=0  
spring.redis.password=pwd  
spring.redis.port=port  
# 连接超时时间  
spring.redis.timeout=1000  
# 连接池最大连接数（使用负值表示没有限制）  
spring.redis.lettuce.pool.max-active=50  
# 连接池中的最小空闲连接  
spring.redis.lettuce.pool.min-idle=5  
# 连接池中的最大空闲连接  
spring.redis.lettuce.pool.max-idle=50  
# 连接池最大阻塞等待时间（使用负值表示没有限制）  
spring.redis.lettuce.pool.max-wait=5000  
#eviction线程调度时间间隔  
spring.redis.pool.time-between-eviction-runs-millis=2000  

 The last configuration here: spring.redis.pool.time-between-eviction-runs-millis=2000 will not take effect in some versions, you need to have a look at DEBUG

LettuceConnectionFactory

Whether the setting is successful in the instance, if not, adjust to the following configuration:

spring.redis.lettuce.pool.time-between-eviction-runs=2000

3. Redis connection configuration class RedisConfiguration.

@Bean  
public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {  
    lettuceConnectionFactory.setShareNativeConnection(false);  
    RedisTemplate<String, Object> template = new RedisTemplate<>();  
    template.setConnectionFactory(lettuceConnectionFactory);  
    //使用Jackson2JsonRedisSerializer替换默认的JdkSerializationRedisSerializer来序列化和反序列化redis的value值  
    Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);  
    ObjectMapper mapper = new ObjectMapper();  
    mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);  
    mapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance,  
        ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);  
    jackson2JsonRedisSerializer.setObjectMapper(mapper);  
    StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();  
    //key采用String的序列化方式  
    template.setKeySerializer(stringRedisSerializer);  
    // hash的key也采用String的序列化方式  
    template.setHashKeySerializer(stringRedisSerializer);  
    // value序列化方式采用jackson  
    template.setValueSerializer(jackson2JsonRedisSerializer);  
    // hash的value序列化方式采用jackson  
    template.setHashValueSerializer(jackson2JsonRedisSerializer);  
    template.afterPropertiesSet();  
    return template;  
}  

SpringBoot+Lettuce single connection method to connect Redis Cluster cluster code example.

1. Add redis-related configuration to the application.properties configuration file.

spring.redis.cluster.nodes=host:port  
spring.redis.cluster.max-redirects=3  
spring.redis.password= pwd 
# 自动刷新时间 
spring.redis.lettuce.cluster.refresh.period=60
# 开启自适应刷新  
spring.redis.lettuce.cluster.refresh.adaptive=true  
spring.redis.timeout=60

2. For the Redis configuration class RedisConfiguration, please be sure to enable cluster auto-refresh topology configuration.

@Bean  
public LettuceConnectionFactory lettuceConnectionFactory() {  
     String[] nodes = clusterNodes.split(",");  
     List<RedisNode> listNodes = new ArrayList();  
     for (String node : nodes) {  
         String[] ipAndPort = node.split(":");  
         RedisNode redisNode = new RedisNode(ipAndPort[0], Integer.parseInt(ipAndPort[1]));  
         listNodes.add(redisNode);  
     }  
     RedisClusterConfiguration redisClusterConfiguration = new RedisClusterConfiguration();  
     redisClusterConfiguration.setClusterNodes(listNodes);  
     redisClusterConfiguration.setPassword(password);  
     redisClusterConfiguration.setMaxRedirects(maxRedirects);  
      // 配置集群自动刷新拓扑 
     ClusterTopologyRefreshOptions topologyRefreshOptions = ClusterTopologyRefreshOptions.builder()  
         .enablePeriodicRefresh(Duration.ofSeconds(period)) //按照周期刷新拓扑  
         .enableAllAdaptiveRefreshTriggers() //根据事件刷新拓扑  
         .build();  

     ClusterClientOptions clusterClientOptions = ClusterClientOptions.builder()  
         //redis命令超时时间,超时后才会使用新的拓扑信息重新建立连接  
         .timeoutOptions(TimeoutOptions.enabled(Duration.ofSeconds(period)))  
         .topologyRefreshOptions(topologyRefreshOptions)  
         .build();  
     LettuceClientConfiguration clientConfig = LettucePoolingClientConfiguration.builder()  
             .commandTimeout(Duration.ofSeconds(timeout))   
             .readFrom(ReadFrom.REPLICA_PREFERRED) // 优先从副本读取  
             .clientOptions(clusterClientOptions)  
             .build();  
     LettuceConnectionFactory factory = new LettuceConnectionFactory(redisClusterConfiguration, clientConfig);  
     return factory;  
}  

@Bean  
public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {  
    RedisTemplate<String, Object> template = new RedisTemplate<>();  
    template.setConnectionFactory(lettuceConnectionFactory);  
    //使用Jackson2JsonRedisSerializer替换默认的JdkSerializationRedisSerializer来序列化和反序列化redis的value值  
    Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);  
    ObjectMapper mapper = new ObjectMapper();  
    mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);  
    mapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance,  
        ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);  
    jackson2JsonRedisSerializer.setObjectMapper(mapper);  
    StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();  
    //key采用String的序列化方式  
    template.setKeySerializer(stringRedisSerializer);  
    // hash的key也采用String的序列化方式  
    template.setHashKeySerializer(stringRedisSerializer);  
    // value序列化方式采用jackson  
    template.setValueSerializer(jackson2JsonRedisSerializer);  
    // hash的value序列化方式采用jackson  
    template.setHashValueSerializer(jackson2JsonRedisSerializer);  
    template.afterPropertiesSet();  
    return template;  
}  

Springboot+lettuce connection pool connection Redis Cluster cluster code example.

1. Add Redis related configuration to the application.properties configuration file.

spring.redis.cluster.nodes=host:port  
spring.redis.cluster.max-redirects=3  
spring.redis.password=pwd 
spring.redis.lettuce.cluster.refresh.period=60  
spring.redis.lettuce.cluster.refresh.adaptive=true  
# 连接超时时间 
spring.redis.timeout=60s   
# 连接池最大连接数（使用负值表示没有限制）  
spring.redis.lettuce.pool.max-active=50  
# 连接池中的最小空闲连接  
spring.redis.lettuce.pool.min-idle=5  
# 连接池中的最大空闲连接  
spring.redis.lettuce.pool.max-idle=50  
# 连接池最大阻塞等待时间（使用负值表示没有限制）  
spring.redis.lettuce.pool.max-wait=5000  
#eviction线程调度时间间隔  
spring.redis.lettuce.pool.time-between-eviction-runs=2000

2. The redis configuration class RedisConfiguration, please be sure to enable the cluster to automatically refresh the topology configuration.

@Bean  
 public LettuceConnectionFactory lettuceConnectionFactory() {  
     GenericObjectPoolConfig genericObjectPoolConfig = new GenericObjectPoolConfig();  
     genericObjectPoolConfig.setMaxIdle(maxIdle);  
     genericObjectPoolConfig.setMinIdle(minIdle);  
     genericObjectPoolConfig.setMaxTotal(maxActive);  
     genericObjectPoolConfig.setMaxWait(Duration.ofMillis(maxWait));  
     genericObjectPoolConfig.setTimeBetweenEvictionRuns(Duration.ofMillis(timeBetweenEvictionRunsMillis));  
     String[] nodes = clusterNodes.split(",");  
     List<RedisNode> listNodes = new ArrayList();  
     for (String node : nodes) {  
         String[] ipAndPort = node.split(":");  
         RedisNode redisNode = new RedisNode(ipAndPort[0], Integer.parseInt(ipAndPort[1]));  
         listNodes.add(redisNode);  
     }  
     RedisClusterConfiguration redisClusterConfiguration = new RedisClusterConfiguration();  
     redisClusterConfiguration.setClusterNodes(listNodes);  
     redisClusterConfiguration.setPassword(password);  
     redisClusterConfiguration.setMaxRedirects(maxRedirects);  
      // 配置集群自动刷新拓扑 
     ClusterTopologyRefreshOptions topologyRefreshOptions = ClusterTopologyRefreshOptions.builder()  
         .enablePeriodicRefresh(Duration.ofSeconds(period)) //按照周期刷新拓扑  
         .enableAllAdaptiveRefreshTriggers() //根据事件刷新拓扑  
         .build();  

     ClusterClientOptions clusterClientOptions = ClusterClientOptions.builder()  
         //redis命令超时时间,超时后才会使用新的拓扑信息重新建立连接  
         .timeoutOptions(TimeoutOptions.enabled(Duration.ofSeconds(period)))  
         .topologyRefreshOptions(topologyRefreshOptions)  
         .build();  
     LettuceClientConfiguration clientConfig = LettucePoolingClientConfiguration.builder()  
             .commandTimeout(Duration.ofSeconds(timeout))  
             .poolConfig(genericObjectPoolConfig)  
             .readFrom(ReadFrom.REPLICA_PREFERRED) // 优先从副本读取  
             .clientOptions(clusterClientOptions)  
             .build();  
     LettuceConnectionFactory factory = new LettuceConnectionFactory(redisClusterConfiguration, clientConfig);  
     return factory;  
 }  

@Bean  
public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {  
    lettuceConnectionFactory.setShareNativeConnection(false);  
    RedisTemplate<String, Object> template = new RedisTemplate<>();  
    template.setConnectionFactory(lettuceConnectionFactory);  
    //使用Jackson2JsonRedisSerializer替换默认的JdkSerializationRedisSerializer来序列化和反序列化redis的value值  
    Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);  
    ObjectMapper mapper = new ObjectMapper();  
    mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);  
    mapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance,  
        ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);  
    jackson2JsonRedisSerializer.setObjectMapper(mapper);  
    StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();  
    //key采用String的序列化方式  
    template.setKeySerializer(stringRedisSerializer);  
    // hash的key也采用String的序列化方式  
    template.setHashKeySerializer(stringRedisSerializer);  
    // value序列化方式采用jackson  
    template.setValueSerializer(jackson2JsonRedisSerializer);  
    // hash的value序列化方式采用jackson  
    template.setHashValueSerializer(jackson2JsonRedisSerializer);  
    template.afterPropertiesSet();  
    return template;  
}  

It is recommended to use the connection pool method.