Spring Boot如何压缩Json并写入redis？

1.为什么需要压缩json？

由于业务需要，存入redis中的缓存数据过大，占用了10+G的内存，内存作为重要资源，需要优化一下大对象缓存，采用gzip压缩存储，可以将 redis 的 kv 对大小缩小大约 7-8 倍，加快存储、读取速度

2.环境搭建

详建redis模块的docker目录

version: '3'
services:
  redis:
    image: registry.cn-hangzhou.aliyuncs.com/zhengqing/redis:6.0.8                   
    container_name: redis                                                             
    restart: unless-stopped                                                                  
    command: redis-server /etc/redis/redis.conf --requirepass 123456 --appendonly no
#    command: redis-server --requirepass 123456 --appendonly yes 
    environment:                        
      TZ: Asia/Shanghai
      LANG: en_US.UTF-8
    volumes:                           
      - "./redis/data:/data"
      - "./redis/config/redis.conf:/etc/redis/redis.conf"  
    ports:                              
      - "6379:6379"

3.代码工程

实验目标

实验存入redis的json数据压缩和解压缩

pom.xml

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>springboot-demo</artifactId>
        <groupId>com.et</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>gzip</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
            <version>2.9.0</version>
        </dependency>

    </dependencies>
</project>

controller

package com.et.gzip.controller;

import com.et.gzip.model.User;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
@Slf4j
public class HelloWorldController {
    @Autowired
    private RedisTemplate redisTemplateWithJackson;

    @PostMapping("/hello")
    public User showHelloWorld(@RequestBody User user){
        log.info("user:"+ user);

        return user;
    }
    @PostMapping("/redis")
    public User redis(@RequestBody User user){
        log.info("user:"+ user);
        redisTemplateWithJackson.opsForValue().set("user",user);
        User redisUser = (User) redisTemplateWithJackson.opsForValue().get("user");
        return redisUser;
    }
}

redis压缩和解压缩配置

压缩类

package com.et.gzip.config;

import com.et.gzip.model.User;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import lombok.extern.slf4j.Slf4j;
import org.apache.tomcat.util.http.fileupload.IOUtils;

import org.springframework.data.redis.serializer.JdkSerializationRedisSerializer;
import org.springframework.data.redis.serializer.SerializationException;
import sun.misc.BASE64Encoder;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.text.SimpleDateFormat;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

@Slf4j
public class CompressRedis extends JdkSerializationRedisSerializer {

    public static final int BUFFER_SIZE = 4096;

    private JacksonRedisSerializer<User>  jacksonRedisSerializer;
    public CompressRedis() {
        this.jacksonRedisSerializer = getValueSerializer();
    }

    @Override
    public byte[] serialize(Object graph) throws SerializationException {
        if (graph == null) {
            return new byte[0];
        }
        ByteArrayOutputStream bos = null;
        GZIPOutputStream gzip = null;
        try {
            // serialize
            byte[] bytes = jacksonRedisSerializer.serialize(graph);
            log.info("bytes size{}",bytes.length);
            bos = new ByteArrayOutputStream();
            gzip = new GZIPOutputStream(bos);

            // compress
            gzip.write(bytes);
            gzip.finish();
            byte[] result = bos.toByteArray();

            log.info("result size{}",result.length);
            //return result;
            return new BASE64Encoder().encode(result).getBytes();
        } catch (Exception e) {
            throw new SerializationException("Gzip Serialization Error", e);
        } finally {
            IOUtils.closeQuietly(bos);
            IOUtils.closeQuietly(gzip);
        }
    }

    @Override
    public Object deserialize(byte[] bytes) throws SerializationException {
        if (bytes == null || bytes.length == 0) {
            return null;
        }
        ByteArrayOutputStream bos = null;
        ByteArrayInputStream bis = null;
        GZIPInputStream gzip = null;
        try {
            bos = new ByteArrayOutputStream();
            byte[] compressed = new sun.misc.BASE64Decoder().decodeBuffer( new String(bytes));;
            bis = new ByteArrayInputStream(compressed);
            gzip = new GZIPInputStream(bis);
            byte[] buff = new byte[BUFFER_SIZE];
            int n;


            // uncompress
            while ((n = gzip.read(buff, 0, BUFFER_SIZE)) > 0) {
                bos.write(buff, 0, n);
            }
            //deserialize
            Object result = jacksonRedisSerializer.deserialize(bos.toByteArray());
            return result;
        } catch (Exception e) {
            throw new SerializationException("Gzip deserizelie error", e);
        } finally {
            IOUtils.closeQuietly(bos);
            IOUtils.closeQuietly(bis);
            IOUtils.closeQuietly(gzip);
        }
    }

    private static JacksonRedisSerializer<User> getValueSerializer() {
        JacksonRedisSerializer<User> jackson2JsonRedisSerializer = new JacksonRedisSerializer<>(User.class);
        ObjectMapper mapper=new ObjectMapper();
        jackson2JsonRedisSerializer.setObjectMapper(mapper);
        return jackson2JsonRedisSerializer;
    }

}

java序列化

package com.et.gzip.config;


import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.type.TypeFactory;
import lombok.extern.slf4j.Slf4j;

import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.SerializationException;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

@Slf4j
public class JacksonRedisSerializer<T> implements RedisSerializer<T> {
    public static final Charset DEFAULT_CHARSET;
    private final JavaType javaType;
    private ObjectMapper objectMapper = new ObjectMapper();

    public JacksonRedisSerializer(Class<T> type) {
        this.javaType = this.getJavaType(type);
    }

    public JacksonRedisSerializer(JavaType javaType) {
        this.javaType = javaType;
    }

    public T deserialize(@Nullable byte[] bytes) throws SerializationException {
        if (bytes == null || bytes.length == 0) {
            return null;
        } else {
            try {
                return this.objectMapper.readValue(bytes, 0, bytes.length, this.javaType);

            } catch (Exception var3) {
                throw new SerializationException("Could not read JSON: " + var3.getMessage(), var3);
            }
        }
    }

    public byte[] serialize(@Nullable Object t) throws SerializationException {
        if (t == null) {
            return  new byte[0];
        } else {
            try {
                return this.objectMapper.writeValueAsBytes(t);
            } catch (Exception var3) {
                throw new SerializationException("Could not write JSON: " + var3.getMessage(), var3);
            }
        }
    }

    public void setObjectMapper(ObjectMapper objectMapper) {
        Assert.notNull(objectMapper, "'objectMapper' must not be null");
        this.objectMapper = objectMapper;
    }

    protected JavaType getJavaType(Class<?> clazz) {
        return TypeFactory.defaultInstance().constructType(clazz);
    }

    static {
        DEFAULT_CHARSET = StandardCharsets.UTF_8;
    }
}

redis序列化

package com.et.gzip.config;

import com.et.gzip.model.User;
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.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;


@Configuration
public class RedisWithJacksonConfig {


    @Bean(name="redisTemplateWithJackson")
    public RedisTemplate<String, User> redisTemplate(LettuceConnectionFactory lettuceConnectionFactory) {

        CompressRedis  compressRedis =  new CompressRedis();
        //redisTemplate
        RedisTemplate<String, User> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(lettuceConnectionFactory);
        RedisSerializer<?> stringSerializer = new StringRedisSerializer();
        redisTemplate.setKeySerializer(stringSerializer);
        redisTemplate.setValueSerializer(compressRedis);
        redisTemplate.setHashKeySerializer(stringSerializer);
        redisTemplate.setHashValueSerializer(compressRedis);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
}

application.yaml

spring:
  redis:
    host: 127.0.0.1
    port: 6379
    database: 10
    password: 123456
    timeout: 10s
    lettuce:
      pool:
        min-idle: 0
        max-idle: 8
        max-active: 8
        max-wait: -1ms
server:
  port: 8088
  compression:
    enabled: true
    mime-types: application/json,application/xml,text/html,text/plain,text/css,application/x-javascript

以上只是一些关键代码，所有代码请参见下面代码仓库

代码仓库

• https://github.com/Harries/springboot-demo(gzip)

4.测试

1. 启动spring boot应用
2. 用postman访问http://127.0.0.1:8088/redis

可以看到redis里面存储的是gzip压缩的内容

查看控制台日志

2024-08-26 14:37:56.445 INFO 43832 --- [nio-8088-exec-5] com.et.gzip.config.CompressRedis : bytes size371
2024-08-26 14:37:56.445 INFO 43832 --- [nio-8088-exec-5] com.et.gzip.config.CompressRedis : result size58

JSON经过gzip压缩，371-->58, 数据大小减少7-8倍

5.引用

• Spring Boot如何压缩Json并写入redis？ | Harries Blog™