我们如何使用 Spring Boot 为 Redis Hash 配置 TTL？答案

【问题标题】：How can we configure TTL for RedisHash using SpringBoot?我们如何使用 Spring Boot 为 Redis Hash 配置 TTL？
【发布时间】：2020-10-01 12:04:45
【问题描述】：

我正在尝试在 RedisHash 上配置 TTL。我想为所有密钥设置相同的到期时间。

第一个：我尝试在实体类上添加注释@RedisHash(value="MyHash",timeToLive=60)。

第二个：使用@TimetoLive 和@RedisHash(value="MyHash",timeToLive=60) 添加一个新字段作为过期字段

@RedisHash(value = "MyHash", timeToLive = 60L)
public class MyHash {
.../attributes with few indexes
     @TimeToLive
    private Long expiration;
}

3rd：添加了带有 KeyspaceConfiguration 的 @EnableRedisRepositories

@EnableRedisRepositories(basePackageClasses = MyHash.class, keyspaceConfiguration = MyKeyspaceConfiguration.class)
public class RedisConfig {
//LettuceConnectionFactory
//RedisTemplate
}

public class MyKeyspaceConfiguration extends KeyspaceConfiguration {
    @Override
    public boolean hasSettingsFor(Class<?> type) {
        return true;
    }

    @Override
    public KeyspaceSettings getKeyspaceSettings(Class<?> type) {

        KeyspaceSettings keyspaceSettings = new KeyspaceSettings(MyHash.class, "MyHashlog");
        keyspaceSettings.setTimeToLive(60L);

        return keyspaceSettings;
    }
}

我的仓库：

public interface MyHashRepository extends CrudRepository<MyHash, Long> {

    List<MyHash> findByApplicationId(String applicationId) ;
}

以上所有方法都没有设置任何到期时间。当我签入 Redis 时，它显示 -1。

TTL MyHash:applicationId:e1hd9-w6q0s-5jd3e-wi2h4
(integer) -1

【问题讨论】：

标签： spring-data-redis

【解决方案1】：

我能够通过两种方式解决这个问题：

解决方案 1：将@EnableRedisHttpSession(maxInactiveIntervalInSeconds = 3600) 添加到我的配置类中

@Configuration
@EnableRedisHttpSession(maxInactiveIntervalInSeconds = 3000)
open class RedisConfig{}

解决方案 2：扩展RedisHttpSessionConfiguration 类并调用setMaxInactiveIntervalInSeconds

@Configuration
open class RedisConfig: RedisHttpSessionConfiguration() {

    @PostConstruct
    open fun afterPropertiesSet() {
        val ttlInSeconds = 3000
        this.setMaxInactiveIntervalInSeconds(ttlInSeconds)
    }

我选择了后者，以便最终将 ttl 添加为配置值。

【讨论】：

这仅适用于spring-session，不适用于spring-data-redis

【解决方案2】：

找到解决方案：我们需要添加 enableKeyspaceEvents = RedisKeyValueAdapter.EnableKeyspaceEvents.ON_STARTUP 属性如下，

方案一：使用@RedisHash设置TTL

//Add annotation on config or Spring boot main class
@EnableRedisRepositories(enableKeyspaceEvents = RedisKeyValueAdapter.EnableKeyspaceEvents.ON_STARTUP)
@SpringBootApplication
public class RedisLogServiceApplication implements WebMvcConfigurer {

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

@RedisHash(value = "MyHash", timeToLive = 60L)
public class MyHash {
.../attributes with few indexes
    @Id
    private Long id;
    @Indexed
    private String applicationId;
}

方案二：使用 KeySapceConfiguration 设置 TTL

//Add annotation on config or Spring boot main class
@EnableRedisRepositories(enableKeyspaceEvents = RedisKeyValueAdapter.EnableKeyspaceEvents.ON_STARTUP, keyspaceConfiguration = MyKeyspaceConfiguration.class)
@SpringBootApplication
public class RedisLogServiceApplication implements WebMvcConfigurer {

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

//MyKeyspaceConfiguration.class to set TTL
public class MyKeyspaceConfiguration extends KeyspaceConfiguration {
    @Override
    public boolean hasSettingsFor(Class<?> type) {
        return true;
    }

    @Override
    public KeyspaceSettings getKeyspaceSettings(Class<?> type) {

        KeyspaceSettings keyspaceSettings = new KeyspaceSettings(MyHash.class, "MyHashlog");
        keyspaceSettings.setTimeToLive(60L);

        return keyspaceSettings;
    }
}

@RedisHash(value = "MyHash")
public class MyHash {
.../attributes with few indexes
    @Id
    private Long id;
    @Indexed
    private String applicationId;
}

存储库没有变化：

public interface MyHashRepository extends CrudRepository<MyHash, Long> {

    List<MyHash> findByApplicationId(String applicationId) ;
}

Spring 还将基于在您的实体类中注释为 @Indexed 的属性创建多个键。但是，TTL 仅适用于主键，即@Id。例如，当我在 redis-cli 中运行 keys 命令时

>keys MyHash*
1) MyHash:id:e1hd9-w6q0s-5jd3e-wi2h4
2) MyHash:applicationId:e1hd9-w6q0s-5jd3e-wi2h4

>TTL MyHash:id:e1hd9-w6q0s-5jd3e-wi2h4
(integer) 59
>TTL MyHash:applicationId:e1hd9-w6q0s-5jd3e-wi2h4
(integer) -1

//After Expiry:
>keys MyHash*
(no keys)
>TTL MyHash:id:e1hd9-w6q0s-5jd3e-wi2h4
(integer) -2

【讨论】：