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Spring Boot 高级篇–Redis(1):基本配置

Mybatis winrains 来源:一灰灰Blog 12个月前 (11-08) 126次浏览

在Spring的应用中,redis可以算是基础操作了。那么想要玩转redis,我们需要知道哪些知识点呢?

  • redis配置,默认,非默认,集群,多实例,连接池参数等
  • redis读写操作,RedisTemplate的基本使用姿势
  • 几种序列化方式对比

本篇博文为redis系列的开篇,将介绍最基本的配置

I. redis基本配置

1. 默认配置

最简单的使用其实开箱即可用,添加依赖

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

本机启动redis,一切采用默认的配置 (host:127.0.0.1, port:6379, 无密码)
然后就可以愉快的玩耍了,可以直接注入redisTemplate实例,进行各种读写操作

@SpringBootApplication
public class Application {
    public Application(RedisTemplate<String, String> redisTemplate) {
        redisTemplate.opsForValue().set("hello", "world");
        String ans = redisTemplate.opsForValue().get("hello");
        Assert.isTrue("world".equals(ans));
    }
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

2. 自定义配置参数

前面是默认的配置参数,在实际的使用中,一般都会修改这些默认的配置项,如果我的应用中,只有一个redis,那么完全可以只修改默认的配置参数
修改配置文件: application.yml

spring:
  redis:
    host: 127.0.0.1
    port: 6379
    password:
    database: 0
    lettuce:
      pool:
        max-active: 32
        max-wait: 300ms
        max-idle: 16
        min-idle: 8

使用和前面没有什么区别,直接通过注入RedisTemplate来操作即可,需要额外注意的是设置了连接池的相关参数,需要额外引入依赖

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

3. 多redis配置

依赖多个不同的redis,也就是说我的项目需要从多个redis实例中获取数据,这种时候,就不能直接使用默认的,需要我们自己来声明ConnectionFactoryRedisTemplate
配置如下

spring:
  redis:
    host: 127.0.0.1
    port: 6379
    password:
    lettuce:
      pool:
        max-active: 32
        max-wait: 300
        max-idle: 16
        min-idle: 8
    database: 0
  local-redis:
    host: 127.0.0.1
    port: 6379
    database: 0
    password:
    lettuce:
      pool:
        max-active: 16
        max-wait: 100
        max-idle: 8
        min-idle: 4

对应的配置类,采用Lettuce,基本设置如下,套路都差不多,先读取配置,初始化ConnectionFactory,然后创建RedisTemplate实例,设置连接工厂

@Configuration
public class RedisAutoConfig {
    @Bean
    public LettuceConnectionFactory defaultLettuceConnectionFactory(RedisStandaloneConfiguration defaultRedisConfig,
            GenericObjectPoolConfig defaultPoolConfig) {
        LettuceClientConfiguration clientConfig =
                LettucePoolingClientConfiguration.builder().commandTimeout(Duration.ofMillis(100))
                        .poolConfig(defaultPoolConfig).build();
        return new LettuceConnectionFactory(defaultRedisConfig, clientConfig);
    }
    @Bean
    public RedisTemplate<String, String> defaultRedisTemplate(
            LettuceConnectionFactory defaultLettuceConnectionFactory) {
        RedisTemplate<String, String> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(defaultLettuceConnectionFactory);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
    @Bean
    @ConditionalOnBean(name = "localRedisConfig")
    public LettuceConnectionFactory localLettuceConnectionFactory(RedisStandaloneConfiguration localRedisConfig,
            GenericObjectPoolConfig localPoolConfig) {
        LettuceClientConfiguration clientConfig =
                LettucePoolingClientConfiguration.builder().commandTimeout(Duration.ofMillis(100))
                        .poolConfig(localPoolConfig).build();
        return new LettuceConnectionFactory(localRedisConfig, clientConfig);
    }
    @Bean
    @ConditionalOnBean(name = "localLettuceConnectionFactory")
    public RedisTemplate<String, String> localRedisTemplate(LettuceConnectionFactory localLettuceConnectionFactory) {
        RedisTemplate<String, String> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(localLettuceConnectionFactory);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
    @Configuration
    @ConditionalOnProperty(name = "host", prefix = "spring.local-redis")
    public static class LocalRedisConfig {
        @Value("${spring.local-redis.host:127.0.0.1}")
        private String host;
        @Value("${spring.local-redis.port:6379}")
        private Integer port;
        @Value("${spring.local-redis.password:}")
        private String password;
        @Value("${spring.local-redis.database:0}")
        private Integer database;
        @Value("${spring.local-redis.lettuce.pool.max-active:8}")
        private Integer maxActive;
        @Value("${spring.local-redis.lettuce.pool.max-idle:8}")
        private Integer maxIdle;
        @Value("${spring.local-redis.lettuce.pool.max-wait:-1}")
        private Long maxWait;
        @Value("${spring.local-redis.lettuce.pool.min-idle:0}")
        private Integer minIdle;
        @Bean
        public GenericObjectPoolConfig localPoolConfig() {
            GenericObjectPoolConfig config = new GenericObjectPoolConfig();
            config.setMaxTotal(maxActive);
            config.setMaxIdle(maxIdle);
            config.setMinIdle(minIdle);
            config.setMaxWaitMillis(maxWait);
            return config;
        }
        @Bean
        public RedisStandaloneConfiguration localRedisConfig() {
            RedisStandaloneConfiguration config = new RedisStandaloneConfiguration();
            config.setHostName(host);
            config.setPassword(RedisPassword.of(password));
            config.setPort(port);
            config.setDatabase(database);
            return config;
        }
    }
    @Configuration
    public static class DefaultRedisConfig {
        @Value("${spring.redis.host:127.0.0.1}")
        private String host;
        @Value("${spring.redis.port:6379}")
        private Integer port;
        @Value("${spring.redis.password:}")
        private String password;
        @Value("${spring.redis.database:0}")
        private Integer database;
        @Value("${spring.redis.lettuce.pool.max-active:8}")
        private Integer maxActive;
        @Value("${spring.redis.lettuce.pool.max-idle:8}")
        private Integer maxIdle;
        @Value("${spring.redis.lettuce.pool.max-wait:-1}")
        private Long maxWait;
        @Value("${spring.redis.lettuce.pool.min-idle:0}")
        private Integer minIdle;
        @Bean
        public GenericObjectPoolConfig defaultPoolConfig() {
            GenericObjectPoolConfig config = new GenericObjectPoolConfig();
            config.setMaxTotal(maxActive);
            config.setMaxIdle(maxIdle);
            config.setMinIdle(minIdle);
            config.setMaxWaitMillis(maxWait);
            return config;
        }
        @Bean
        public RedisStandaloneConfiguration defaultRedisConfig() {
            RedisStandaloneConfiguration config = new RedisStandaloneConfiguration();
            config.setHostName(host);
            config.setPassword(RedisPassword.of(password));
            config.setPort(port);
            config.setDatabase(database);
            return config;
        }
    }
}

测试类如下,简单的演示下两个template的读写

@SpringBootApplication
public class Application {
    public Application(RedisTemplate<String, String> localRedisTemplate, RedisTemplate<String, String>
            defaultRedisTemplate)
            throws InterruptedException {
        // 10s的有效时间
        localRedisTemplate.delete("key");
        localRedisTemplate.opsForValue().set("key", "value", 100, TimeUnit.MILLISECONDS);
        String ans = localRedisTemplate.opsForValue().get("key");
        System.out.println("value".equals(ans));
        TimeUnit.MILLISECONDS.sleep(200);
        ans = localRedisTemplate.opsForValue().get("key");
        System.out.println("value".equals(ans) + " >> false ans should be null! ans=[" + ans + "]");
        defaultRedisTemplate.opsForValue().set("key", "value", 100, TimeUnit.MILLISECONDS);
        ans = defaultRedisTemplate.opsForValue().get("key");
        System.out.println(ans);
    }
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

上面的代码执行演示如下
showcaseshowcase
上面的演示为动图,抓一下重点:

  • 注意 localRedisTemplate, defaultRedisTemplate 两个对象不相同(看debug窗口后面的@xxx)
  • 同样两个RedisTemplateConnectionFactory也是两个不同的实例(即分别对应前面配置类中的两个Factory)
  • 执行后输出的结果正如我们预期的redis操作
    • 塞值,马上取出没问题
    • 失效后,再查询,返回null
  • 最后输出异常日志,提示如下
Description:
Parameter 0 of method redisTemplate in org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration required a single bean, but 2 were found:
  - defaultLettuceConnectionFactory: defined by method 'defaultLettuceConnectionFactory' in class path resource [com/git/hui/boot/redis/config/RedisAutoConfig.class]
  - localLettuceConnectionFactory: defined by method 'localLettuceConnectionFactory' in class path resource [com/git/hui/boot/redis/config/RedisAutoConfig.class]
Action:
Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed

上面表示说有多个ConnectionFactory存在,然后创建默认的RedisTemplate就不知道该选择哪一个了,有两种方法
方法一:指定默认的ConnectionFactory
借助@Primary来指定默认的连接工厂,然后在使用工程的时候,通过@Qualifier注解来显示指定,我需要的工厂是哪个(主要是localRedisTemplate这个bean的定义,如果不加,则会根据defaultLettuceConnectionFactory这个实例来创建Redis连接了)

@Bean
@Primary
public LettuceConnectionFactory defaultLettuceConnectionFactory(RedisStandaloneConfiguration defaultRedisConfig,
        GenericObjectPoolConfig defaultPoolConfig) {
    // ...
}
@Bean
public RedisTemplate<String, String> defaultRedisTemplate(
        @Qualifier("defaultLettuceConnectionFactory") LettuceConnectionFactory defaultLettuceConnectionFactory) {
    // ....
}
@Bean
@ConditionalOnBean(name = "localRedisConfig")
public LettuceConnectionFactory localLettuceConnectionFactory(RedisStandaloneConfiguration localRedisConfig,
        GenericObjectPoolConfig localPoolConfig) {
    // ...
}
@Bean
@ConditionalOnBean(name = "localLettuceConnectionFactory")
public RedisTemplate<String, String> localRedisTemplate(
        @Qualifier("localLettuceConnectionFactory") LettuceConnectionFactory localLettuceConnectionFactory) {
    // ...
}

方法二:忽略默认的自动配置类
既然提示的是org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration类加载bean冲突,那么就不加载这个配置即可

@SpringBootApplication
@EnableAutoConfiguration(exclude = {RedisAutoConfiguration.class, RedisReactiveAutoConfiguration.class})
public class Application {
    // ...
}

作者:一灰灰Blog

来源:http://spring.hhui.top/spring-blog/2018/10/29/181029-SpringBoot%E9%AB%98%E7%BA%A7%E7%AF%87Redis%E4%B9%8B%E5%9F%BA%E6%9C%AC%E9%85%8D%E7%BD%AE/


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