目录

RedisSpringboot集成Redis

Redis|Springboot集成Redis

https://i-blog.csdnimg.cn/direct/588cfe4a36014749b88f137cabf52291.png

总体概述

  • jedis-lettuce-RedisTemplate三者的联系
    • jedis第一代
    • lettuce承上启下
    • redistemplate着重使用

本地Java连接Redis常见问题

  • bind配置请注释掉
  • 保护模式设置为no
  • Linux系统的防火墙设置
  • Redis服务器的IP地址和密码是否正确
  • 忘记写访问redis的服务端口号和auth密码

集成Jedis

  • 是什么:Jedis Client是Redis官网推荐的一个面向Java客户端,库文件实现了对各类API进行封装调用
  • 步骤
    1. 建Module
    2. 改POM.xml
    3. 写application.yaml
    4. 主启动
    5. 业务类
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.11</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.luojia</groupId>
    <artifactId>redis7_study</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>redis7_study</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>
    </properties>

    <dependencies>
        <!--SpringBoot 通用依赖模块-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- jedis -->
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>4.3.1</version>
        </dependency>
        <!-- 通用基础配置 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>${lombok.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>
server.port=7777
spring.application.name=redis7_study

https://i-blog.csdnimg.cn/direct/c050ec341de5412b976eedecc6fdbf76.png https://i-blog.csdnimg.cn/direct/7cf038a7cab345f28335f5f03e682e4f.png

集成lettuce

  • 是什么:Lettuce是一个Redis的Java驱动包,Lettuce翻译为生菜,就是吃的那种生菜
  • lettuce VS Jedis https://i-blog.csdnimg.cn/direct/b053010e9104414382de7a247a847262.png
  • 改POM https://i-blog.csdnimg.cn/direct/13af70cf90c247eb958f15f3c1471163.png
  • 业务类 https://i-blog.csdnimg.cn/direct/08904274e967488aa8b1ba9093e2470a.png https://i-blog.csdnimg.cn/direct/090808beeb7f4544b9ffaee3362a9d9d.png

集成RedisTemplate——推荐使用

连接单机

  • boot整合Redis基础演示
  • 建module:redis7_study
  • 改pom
<!-- SpringBoot 与Redis整合依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
        </dependency>
        <!-- swagger2 -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>
  • 写YML
server.port=7777

spring.application.name=redis7_study

# ===========================logging===========================
logging.level.root=info
logging.1evel.com.luojia.redis7_study.redis7=info
1ogging.pattern.console=%d{yyyy-MM-dd HH:m:ss.SSS} [%thread] %-5level %1ogger- %msg%n

1ogging.file.name=F:\workspace\数据结构和算法\Learning-in-practice\Redis\redis7-study
1ogging.pattern.fi1e=%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger- %msg%n

# ===========================swagge===========================
spring.swagger2.enabled=true
#在springboot2.6.X结合swagger2.9.X会提示documentationPluginsBootstrapper空指针异常,
#原因是在springboot2.6.X中将SpringMVC默认路径匹配策略MAntPathMatcher更改为athPatternParser,
#导致出错,解决办法是matching-strategy 切换回之前ant_path_matcher
spring.mvc.pathmatch.matching-strategy=ant_path_matcher

# ===========================redis单机===========================
spring.redis.database=0
#修改为自己真实IP
spring.redis.host=127.0.0.1
spring.redis.port=6379
spring.redis.password=123456
spring.redis.lettuce.pool.max-active=8
spring.redis.1ettuce.pool.max-wait=-1ms
spring.redis.1ettuce.pool.max-idle=8
spring.redis.lettuce.pool.min-idle=0
  • 主启动 https://i-blog.csdnimg.cn/direct/a0c866e18c774920b1d6291a1ede2434.png
  • 业务类-配置类
// RedisConfig
package com.luojia.redis7_study.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

@Configuration
public class RedisConfig {

    /**
     * *redis序列化的工具定置类,下面这个请一定开启配置
     * *127.0.0.1:6379> keys *
     * *1) “ord:102” 序列化过
     * *2)“\xaclxedlxeelx05tixeelaord:102” 野生,没有序列化过
     * *this.redisTemplate.opsForValue(); //提供了操作string类型的所有方法
     * *this.redisTemplate.opsForList();// 提供了操作List类型的所有方法
     * *this.redisTemplate.opsForset(); //提供了操作set类型的所有方法
     * *this.redisTemplate.opsForHash(); //提供了操作hash类型的所有方认
     * *this.redisTemplate.opsForZSet(); //提供了操作zset类型的所有方法
     * param LettuceConnectionFactory
     * return
     */
    @Bean
    public RedisTemplate<String, Object> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {
        RedisTemplate<String,Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(lettuceConnectionFactory);
        // 设置key序列化方式string
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        // 设置value的序列化方式json,使用GenericJackson2JsonRedisSerializer替换默认序列化
        redisTemplate.setValueSerializer(new GenericJackson2JsonRedisSerializer());

        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        redisTemplate.setHashValueSerializer(new GenericJackson2JsonRedisSerializer());
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
}
// SwaggerConfig
package com.luojia.redis7_study.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

@Configuration
@EnableSwagger2
public class SwaggerConfig {

    @Value("${spring.swagger2.enabled}")
    private Boolean enabled;

    @Bean
    public Docket createRestApi() {
        return new Docket (DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo())
                .enable(enabled)
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.luojia.redis7_study.config")) //你自己的package
                .paths (PathSelectors.any())
                .build();

    }

    public ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("springboot利用swagger2构建api接口文档 "+"\t"
                        + DateTimeFormatter.ofPattern("yyyy-MM-dd").format(LocalDate.now()))
                .description( "springboot+redis整合" )
                .version("1.0")
                .termsOfServiceUrl("https://github.com/Romantic-Lei")
                .build();
    }

}
  • 业务类-service
package com.luojia.redis7_study.service;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;

import java.util.UUID;
import java.util.concurrent.ThreadLocalRandom;

@Service
@Slf4j
public class OrderService {

    @Autowired
    private RedisTemplate redisTemplate;

    public static final String ORDER_KEY="ord:";

    public void addOrder() {
        int keyId = ThreadLocalRandom.current().nextInt(1000) + 1;
        String serialNo = UUID.randomUUID().toString();
        String key = ORDER_KEY+keyId;
        String value = "JD" + serialNo;
        redisTemplate.opsForValue().set(key, value);
        log.info("***key:{}", key);
        log.info("***value:{}", value);

    }

    public String getOrderById(Integer keyId) {
        return (String)redisTemplate.opsForValue().get(ORDER_KEY+keyId);
    }
}
  • 业务类-controller
package com.luojia.redis7_study.controller;

import com.luojia.redis7_study.service.OrderService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.models.auth.In;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@Slf4j
@Api(tags="订单接口")
public class OrderController {

    @Autowired
    private OrderService orderService;

    @ApiOperation("新增订单")
    @PostMapping("/order/add")
    public void addOrder() {
        orderService.addOrder();
    }

    @ApiOperation("根据keyId查询订单")
    @GetMapping("/order/query")
    public String queryOrder(Integer keyId) {
        return orderService.getOrderById(keyId);
    }

}
  • 测试
    • 项目启动,连接swagger:

    • 序列化问题 https://i-blog.csdnimg.cn/direct/8be709c359ee434cb7cdb133a59aa2fe.png

    • 为什么会这样?RedisTemplate使用的是JDK序列化方式(默认)惹的祸 https://i-blog.csdnimg.cn/direct/09e4193fe89b48ada6aa8ff0ee0c4035.png

      https://i-blog.csdnimg.cn/direct/e55ebc8cf9e04fb1a0331678d665f79b.png https://i-blog.csdnimg.cn/direct/e245c94d24214f3f8035ae779b8c3980.png

连接集群

  • 启动Redis集群6台实例
  • 第一次改写YML
# ===========================redis集群===========================
spring.redis.password=111111
# 获取失败 最大重定向次数
spring.redis.cluster.max-redirects=3
spring.redis.lettuce.pool.max-active=8
spring.redis.1ettuce.pool.max-wait=-1ms
spring.redis.1ettuce.pool.max-idle=8
spring.redis.lettuce.pool.min-idle=0
spring.redis.cluster.nodes=192.168.111.175:6381,192.168.111.175:6382,192.168.111.176:6383,192.168.111.176:6384
  • 直接通过微服务访问Redis集群:一切正常 ( )
  • 问题来了:
    1. 人为模拟,master-6381机器意外宕机,手动shutdown
    2. 先对redis集群用命令的方式,手动验证各种读写命令,看看6384是否上位
    3. Redis Cluster集群能自动感知并自动完成主备切换,对应的slave6384会被选举为新的master节点
    4. 通过redis客户端连接6384可以正常进行读写操作
    5. 微服务客户端再次读写访问试试
      • 故障现象

        • SpringBoot客户端没有动态感知RedisCluster的最新集群信息
        • 经典故障-故障演练:Redis Cluster集群部署采用了3主3从拓扑结构,数据读写访问master节点,slave节点负责备份。当master宕机主从切换成功,redis手动OK,but 2个经典故障 https://i-blog.csdnimg.cn/direct/2558753fad5047b696b42d641fc9556d.png
      • 导致原因:SpringBoot 2.X版本,Redis默认的连接池采用Lettuce,当Redis集群节点发生变化后,Letture默认是不会刷新节点拓扑

      • 解决方案

        1. 排除lettuce采用Jedis(不推荐) https://i-blog.csdnimg.cn/direct/2934de75eda8440095949da578bb443b.png
        2. 修改源码,重写连接工厂实例(极度不推荐)
        3. 刷新节点集群拓扑动态感应 https://i-blog.csdnimg.cn/direct/7fc3b73bad10429280a745d0bea43a3c.png
          • 解决方法:
            • 调用 RedisClusterClient.reloadPartitions
            • 后台基于时间间隔的周期刷新
            • 后台基于持续的断开和移动、重定向的自适应更新
      • 第二次改写YML https://i-blog.csdnimg.cn/direct/ca604759d915444fbb6f9779d683954e.png