数据库 Redis

Redis 操作多个数据库的配置的方法实现

Posted in Redis onMarch 23, 2022

前言

redis 默认有 0-16 号数据库，一般我们操作redis时，用的是 0号数据库，但是有时我们的项目想同时操作多个数据库，又不想每次访问其它库数据时 select 切换数据库，这样太繁琐。

因此我们需要配置多个Jedis Client，但是jedis是容易阻塞，效率不太好，所以我这边采用了 Lettuce Client，它是 Reactive 的连接方式，效率比较高。但是怎么使用到 Lettuce Client，其实一般我们添加 spring-boot-starter-data-redis 依赖，通过RedisTemplate 去使用Redis的功能时，当版本很高的时候默认RedisTemplate底层用的就是通过Lettuce Client 去建立连接和操作数据。

以下是自己实际正在使用的多数据源配置，且能正常运行。

一、添加pom 依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
    <version>2.0.5.RELEASE</version>
</dependency>

二、多数据源的配置和添加到spring容器中

下面我的截图使用了四个数据源，分别是1，2，3，4号库。

1）新建一个configuration 配置类

2）new RedisStandaloneConfiguration(host, port); 初始化一个Redis配置，并接下来选择好库号。

3）初始化一个 LettuceConnectionFactory 。

4）实例化一个 RedisTemplate ，并设置键值序列化的方式，这里key和value都是字符串的，所以序列化器选择 StringRedisSerializer。

5）给 RedisTemplate 设置第三步创建的 LettuceConnectionFactory，并以@Bean注解注入到spring容器中，使用时直接通过方法名字在spring容器中查找，装配到引用它的实例中。

import io.lettuce.core.resource.ClientResources;
import io.lettuce.core.resource.DefaultClientResources;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.springframework.beans.factory.annotation.Value;
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.RedisPassword;
import org.springframework.data.redis.connection.RedisStandaloneConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceClientConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.connection.lettuce.LettucePoolingClientConfiguration;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import org.springframework.util.ObjectUtils;
 
import java.time.Duration;
 
/**
* reactive redis
* @Author:wangqipeng
* @Date:14:38 2019-07-03
*/
 
@Configuration
public class RedisDatasourceConfiguration {
 
    @Value("${redis.isCleanRedisCache:false}")
    private String cleanRedisCache;
    @Value("${redis.host:127.0.0.1}")
    public String host;
    @Value("${redis.port:6379}")
    public Integer port;
    private String password;
 
    @Value("${redis.timeout:2000}")
    public Integer timeout;
    public Integer maxIdle = 16;
    public Integer minIdle = 5;
    public Integer maxTotal = 30;
 
 
    @Bean
    public RedisTemplate<String, String> stringRedisTemplate1() {
        RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration(host, port);
        configuration.setDatabase(1);
        if (!ObjectUtils.isEmpty(password)) {
            RedisPassword redisPassword = RedisPassword.of(password);
            configuration.setPassword(redisPassword);
        }
        return createRedisTemplate(creatFactory(configuration));
    }
 
    @Bean
    public RedisTemplate<String, String> stringRedisTemplate2() {
        RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration(host, port);
        configuration.setDatabase(2);
        if (!ObjectUtils.isEmpty(password)) {
            RedisPassword redisPassword = RedisPassword.of(password);
            configuration.setPassword(redisPassword);
        }
        return createRedisTemplate(creatFactory(configuration));
    }
    @Bean
    public RedisTemplate<String, String> stringRedisTemplate3() {
        RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration(host, port);
        configuration.setDatabase(3);
        if (!ObjectUtils.isEmpty(password)) {
            RedisPassword redisPassword = RedisPassword.of(password);
            configuration.setPassword(redisPassword);
        }
        return createRedisTemplate(creatFactory(configuration));
    }
    @Bean
    public RedisTemplate<String, String> stringRedisTemplate4() {
        RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration(host, port);
        configuration.setDatabase(4);
        if (!ObjectUtils.isEmpty(password)) {
            RedisPassword redisPassword = RedisPassword.of(password);
            configuration.setPassword(redisPassword);
        }
        return createRedisTemplate(creatFactory(configuration));
    }
 
    @Bean
    public RedisTemplate<String, String> stringRedisTemplate5() {
        RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration(host, port);
        configuration.setDatabase(5);
        if (!ObjectUtils.isEmpty(password)) {
            RedisPassword redisPassword = RedisPassword.of(password);
            configuration.setPassword(redisPassword);
        }
        return createRedisTemplate(creatFactory(configuration));
    }
 
    private RedisTemplate<String, String> getSerializerRedisTemplate(){
        RedisTemplate<String, String> redisTemplate = new RedisTemplate<>();
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        redisTemplate.setHashValueSerializer(new StringRedisSerializer());
        return redisTemplate;
    }
 
    private RedisTemplate createRedisTemplate(RedisConnectionFactory redisConnectionFactory) {
        RedisTemplate<String, String> redisTemplate = getSerializerRedisTemplate();
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
    private GenericObjectPoolConfig getGenericObjectPoolConfig(){
        GenericObjectPoolConfig genericObjectPoolConfig = new GenericObjectPoolConfig();
        genericObjectPoolConfig.setMaxTotal(maxTotal);
        genericObjectPoolConfig.setMinIdle(minIdle);
        genericObjectPoolConfig.setMaxIdle(maxIdle);
        genericObjectPoolConfig.setMaxWaitMillis(timeout);
        return genericObjectPoolConfig;
    }
 
    private LettuceConnectionFactory creatFactory(RedisStandaloneConfiguration configuration){
        LettucePoolingClientConfiguration.LettucePoolingClientConfigurationBuilder builder = LettucePoolingClientConfiguration.builder();
        builder.poolConfig(getGenericObjectPoolConfig());
 
//        LettuceClientConfiguration.LettuceClientConfigurationBuilder builder = LettuceClientConfiguration.builder();
//        builder.clientResources(clientResources());
//        builder.commandTimeout(Duration.ofSeconds(3000));
        LettuceConnectionFactory connectionFactory = new LettuceConnectionFactory(configuration, builder.build());
        connectionFactory.afterPropertiesSet();
        return connectionFactory;
    }
}