spring data redis-1

Spring Data Redis

写在前面的话

想要快速集成redis这种kv型缓存数据库到项目中,完成后端代码的正常crud操作以及服务器中服务的启动关闭

服务器中

这里使用docker,docker是一种容器技术用来运行极其紧密的服务,服务生存在镜像中,镜像运行时成为容器，容载服务运行,镜像的存储运用了联合文件系统的思想,将最终需要依赖的文件镜像分层,使得在使用类似的镜像时能够重用数据，但是对于上层镜像来说，下层镜像是不可修改的，只能通过覆盖文件的方式达到修改的操作,容器运行时是严格按照makefile的规范的,容器内部映射端口的规则为通过-p参数去指定映射指定参数端口到容器内部

获取镜像

docker pull docker.io/redis

运行镜像

docker run --name redis -v /linyi/docker/redis:/data -p 6379:6379 -d  redis redis-server --appendonly yes

–name redis ,指定容器名称

-v /linyi/docker/redis:/data ,指定数据卷存放位置

-p 6379:6379 ,映射端口,hostPort:containerPort

-d ,后台方式启动

redis-server :服务端启动

–appendonly yes 持久化支持

停止容器

docker stop container_id

后台中

这里使用spring boot,spring boot基于spring 4.0,内置很多依赖管理,在使用spring全家桶时是非常适合的

pom.xml中

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

application.properties/application.yml中

spring.redis.host=hostname
spring.redis.port=6379

启动类中-XxxApplication

@EnableRedisRepositories

entity–PersonRedis、Address、Gender

Repository其实是基于实体的,PersonRedis是与redis直接关联的对象,Address是为了测试属性集合中存放对象，Gender是为了测试枚举类

package com.linyi.spring_data_redis_repository_demo.entity;
public enum Gender {
    BOY,GIRL
}
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package com.linyi.spring_data_redis_repository_demo.entity;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
@Data
@AllArgsConstructor
@Builder
public class Address {
    private String id;
    private String name;
}
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package com.linyi.spring_data_redis_repository_demo.entity;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Reference;
import org.springframework.data.redis.core.RedisHash;
import org.springframework.data.redis.core.index.Indexed;
import java.util.List;
@RedisHash("persons") //prefix
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class PersonRedis {
    @Id private String id; //it will gennerate the uuid value to id when it's null ,so allow id is null
    @Indexed private String secondaryId; //the seconde prefix ,if add this there will become persons:secondaryId,and if below has more secondary index ,it will be ordered like `:theNextName`
    @Reference private List<PersonRedis> others;
    private String name;
    private Gender gender;
}

repository-PersonRedisRepository:

package com.linyi.spring_data_redis_repository_demo.repository;
import com.linyi.spring_data_redis_repository_demo.entity.PersonRedis;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface PersonRedisRepository  extends CrudRepository<PersonRedis,String>{
    Page<PersonRedis> findAll(Pageable page);
}

test-PersonRedisTest:

package com.linyi.spring_data_redis_repository_demo;
import com.linyi.spring_data_redis_repository_demo.entity.Gender;
import com.linyi.spring_data_redis_repository_demo.entity.PersonRedis;
import com.linyi.spring_data_redis_repository_demo.repository.PersonRedisRepository;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.UUID;
@RunWith(SpringRunner.class)
@SpringBootTest
public class PersonRedisTests {
    @Autowired
    PersonRedisRepository redisRepository;
    List<PersonRedis> savedData = new ArrayList<>();
    /**
the result of run
save = PersonRedis(id=12a72b27-837e-4c86-8f05-f8ee58e2efe3, secondaryId=secondaryId, others=null, name=linyi, gender=BOY)
save1 = PersonRedis(id=dd015ebc-7fa6-4f84-a89d-edb59dc4d943, secondaryId=secondaryId, others=[PersonRedis(id=12a72b27-837e-4c86-8f05-f8ee58e2efe3, secondaryId=secondaryId, others=null, name=linyi, gender=BOY)], name=linyi, gender=BOY)
     * */
    @Test
    public void testAdd() {
        // object can thought call builder to get a builder data object,but last data will be losed ,so sometimes you just before in use it to use it's builder object
        PersonRedis.PersonRedisBuilder personRedisBuilder = PersonRedis.builder().gender(Gender.BOY).name("linyi").secondaryId("secondaryId");
        PersonRedis save = redisRepository.save(personRedisBuilder.build());
        System.out.println("save = " + save);
        PersonRedis save1 = redisRepository.save(personRedisBuilder.others(Arrays.asList(save)).build()); //so if want to save some reference data list ,you should to make sure that there are already exit id-value in reids,so you can do better do it like before that operation is to save data
        // redis can't cascade add data,but when  find data it will use cascade ,so you must sure that data is already exits
        System.out.println("save1 = " + save1);
    }
    @Test
    public void testFindAll() {
        Iterable<PersonRedis> all = redisRepository.findAll();
        all.forEach(t->{
            System.out.println(t.toString());
        });
    }
    /**run this method to reset current test result and you cat test against ,it will delete all data in redis with Person.RedisHash.value-value ,so must be careful*/
    @Test
    public void testRemoveAll() {
        redisRepository.deleteAll();
    }
    @Test
    public void testFindOne() {
        PersonRedis one = redisRepository.findOne("dd015ebc-7fa6-4f84-a89d-edb59dc4d943");
        System.out.println("one = " + one);
    }
        @Test
    public void testUpdateOne() {
        PersonRedis one = redisRepository.findOne("dd015ebc-7fa6-4f84-a89d-edb59dc4d943");
        one.setName("updateName");
        PersonRedis update = redisRepository.save(one);
        System.out.println("update = " + update);
    }
/*
* exists = true
notExists = false
* */
    @Test
    public void testExist() {
        boolean exists = redisRepository.exists("dd015ebc-7fa6-4f84-a89d-edb59dc4d943");
        System.out.println("exists = " + exists);
        boolean notExists = redisRepository.exists("dd015ebc-7fa6-4f84-a89d-edb59dc4d94312123");
        System.out.println("notExists = " + notExists);
    }
}
    @Test
    public void testPageFind(){
        System.out.println("findAllPage================================>");
        PageRequest pageRequest = new PageRequest(0, 4);
        Page<PersonRedis> all = redisRepository.findAll(pageRequest);
        all.iterator().forEachRemaining(t->{
            System.out.println(t);
        });
        System.out.println("findAllPage================================>");
    }

写在后面的话

redis功能很强大,spring data redis有很多个例子，但是这里只是介绍一点点repository相关的,从redis的角度讲,五种数据类型,String/Set/ZSet/Hash/List,repository只是用到了Hash,但是也是足够的面对一些小问题的