Redis生成分佈式系統全局唯一ID的實現

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分佈式系統全局唯一ID

在互聯網系統中，並發越大的系統，數據就越大，數據越大就越需要分佈式，而大量的分佈式數據就越需要唯一標識來識別它們。

例如淘寶的商品系統有千億級別商品，訂單系統有萬億級別的訂單數據，這些數據都是日漸增長，傳統的單庫單表是無法支撐這種級別的數據，必須對其進行分庫分表；一旦分庫分表，表的自增ID就失去瞭意義；故需要一個全局唯一的ID來標識每一條數據（商品、訂單）。

e.g: 一張表1億條數據，被分庫分表10張表，原先的ID就失去意義，所以需要全局唯一ID來標識10張表的數據。

全局唯一的ID生成的技術方案有很多，業界比較有名的有 UUID、Redis、Twitter的snowflake算法、美團Leaf算法。

基於Redis INCR 命令生成分佈式全局唯一ID

INCR 命令主要有以下2個特征：

  • Redis的INCR命令具備瞭“INCR AND GET”的原子操作
  • Redis是單進程單線程架構，INCR命令不會出現ID重復

基於以上2個特性，可以采用INCR命令來實現分佈式全局ID生成。

采用Redis生成商品全局唯一ID

Project Directory

Maven Dependency

<?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>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.8.RELEASE</version>
        <relativePath/>
    </parent>

    <modelVersion>4.0.0</modelVersion>

    <groupId>org.fool.redis</groupId>
    <artifactId>redis-string-id</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

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

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

application.properties

spring.application.name=redis-spring-id
server.port=8888

spring.redis.host=localhost
spring.redis.port=6379
spring.redis.database=0
spring.redis.password=
spring.redis.timeout=2000
spring.redis.pool.max-active=10
spring.redis.pool.max-wait=1000
spring.redis.pool.max-idle=10
spring.redis.pool.min-idle=5
spring.redis.pool.num-tests-per-eviction-run=1024
spring.redis.pool.time-between-eviction-runs-millis=30000
spring.redis.pool.min-evictable-idle-time-millis=60000
spring.redis.pool.soft-min-evictable-idle-time-millis=10000
spring.redis.pool.test-on-borrow=true
spring.redis.pool.test-while-idle=true
spring.redis.pool.block-when-exhausted=false

SRC

Application.java

package org.fool.redis;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

Product.java

package org.fool.redis.model;

import lombok.Data;

import java.math.BigDecimal;

@Data
public class Product {
    private Long id;
    private String name;
    private BigDecimal price;
    private String detail;
}

IdGeneratorService.java

package org.fool.redis.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

@Service
public class IdGeneratorService {
    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    private static final String ID_KEY = "id:generator:product";

    public Long incrementId() {
        return stringRedisTemplate.opsForValue().increment(ID_KEY);
    }
}

ProductController.java

package org.fool.redis.controller;

import lombok.extern.slf4j.Slf4j;
import org.fool.redis.model.Product;
import org.fool.redis.service.IdGeneratorService;
import org.springframework.beans.factory.annotation.Autowired;
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;

@RestController
@Slf4j
@RequestMapping(value = "/product")
public class ProductController {
    @Autowired
    private IdGeneratorService idGeneratorService;

    @PostMapping(value = "/create")
    public String create(@RequestBody Product obj) {
        //生成分佈式id
        long id = idGeneratorService.incrementId();

        //使用全局id 代替數據庫的自增id
        obj.setId(id);

        //取模(e.g: 這裡分為8張表，海量數據可以分為1024張表)，計算表名
        int table = (int) id % 8;
        String tableName = "product_" + table;

        log.info("insert to table: {}, with content: {}", tableName, obj);

        return "insert to table: " + tableName + " with content: " + obj;
    }
}

Test

curl --location --request POST 'http://localhost:8888/product/create' \
--header 'Content-Type: application/json' \
--data-raw '{
    "name": "Car",
    "price": "300000.00",
    "detail": "Lexus Style"
}'

Console Output

到此這篇關於Redis生成分佈式系統全局唯一ID的實現的文章就介紹到這瞭,更多相關Redis生成分佈式系統全局唯一ID內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！

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