如何启用分布式/集群缓存时使用redis与Spring数据高速缓存

Question

如何启用分布式/集群缓存时使用Redis与Spring启动缓存。

尤其是通过spring boot starter data Redis

Answer 1

在Spring引导应用程序中启用缓存非常简单。你只需要遵循三个步骤。

• 定义缓存配置

对于Redis，我们有可以配置和创建的RedisCacheManager。

缓存配置

@Configuration
@Getter
@Setter
@ConfigurationProperties(prefix = "cache")
public class CacheConfigurationProperties {
 // Redis host name
  private String redisHost;
 // Redis port
  private int redisPort;
  // Default TTL
  private long timeoutSeconds;
  // TTL per cache, add enties for each cache
  private Map<String, Long> cacheTtls;
}

通过属性或yaml文件设置其值，如

cache.redisHost=localhost
cache.redisPort=6379
cache.timeoutSeconds=1000
cache.cacheTtls.cach1=100
cache.cacheTtls.cach2=200

创建配置后，可以通过构建器为RedisCacheManger创建缓存配置。

@Configuration
@EnableCaching
public class CacheConfig {
  private static RedisCacheConfiguration createCacheConfiguration(long timeoutInSeconds) {
    return RedisCacheConfiguration.defaultCacheConfig()
        .entryTtl(Duration.ofSeconds(timeoutInSeconds));
  }

  @Bean
  public LettuceConnectionFactory redisConnectionFactory(CacheConfigurationProperties properties) {
    RedisStandaloneConfiguration redisStandaloneConfiguration = new RedisStandaloneConfiguration();
    redisStandaloneConfiguration.setHostName(properties.getRedisHost());
    redisStandaloneConfiguration.setPort(properties.getRedisPort());
    return new LettuceConnectionFactory(redisStandaloneConfiguration);
  }

  @Bean
  public RedisCacheConfiguration cacheConfiguration(CacheConfigurationProperties properties) {
    return createCacheConfiguration(properties.getTimeoutSeconds());
  }

  @Bean
  public CacheManager cacheManager(
      RedisConnectionFactory redisConnectionFactory, CacheConfigurationProperties properties) {
    Map<String, RedisCacheConfiguration> cacheConfigurations = new HashMap<>();

    for (Entry<String, Long> cacheNameAndTimeout : properties.getCacheTtls().entrySet()) {
      cacheConfigurations.put(
          cacheNameAndTimeout.getKey(), createCacheConfiguration(cacheNameAndTimeout.getValue()));
    }

    return RedisCacheManager.builder(redisConnectionFactory)
        .cacheDefaults(cacheConfiguration(properties))
        .withInitialCacheConfigurations(cacheConfigurations)
        .build();
  }
}

如果您使用的是Redis cluster，请根据此更新缓存属性。在这种情况下，如果您想要缓存特定的bean，而不是将这些方法私有化，那么一些bean将成为主bean。