服务器之家：专注于服务器技术及软件下载分享
分类导航

node.js|vue.js|jquery|angularjs|React|json|js教程|

服务器之家 - 编程语言 - JavaScript - Js Snowflake(雪花算法)生成随机ID的实现方法

Js Snowflake(雪花算法)生成随机ID的实现方法

2021-08-31 16:47柳非 JavaScript

这篇文章主要介绍了Js Snowflake(雪花算法)生成随机ID的实现方法，文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

1、snowflake-id插件 

?
1
2
3
4
5
6
import SnowflakeId from "snowflake-id";
 
const guid = num => {
 const id= new SnowflakeId();
 return id.generate();
};

2、原生使用 

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
var Snowflake = /** @class */ (function() {
    function Snowflake(_workerId, _dataCenterId, _sequence) {
        this.twepoch = 1288834974657n;
        //this.twepoch = 0n;
        this.workerIdBits = 5n;
        this.dataCenterIdBits = 5n;
        this.maxWrokerId = -1n ^ (-1n << this.workerIdBits); // 值为：31
        this.maxDataCenterId = -1n ^ (-1n << this.dataCenterIdBits); // 值为：31
        this.sequenceBits = 12n;
        this.workerIdShift = this.sequenceBits; // 值为：12
        this.dataCenterIdShift = this.sequenceBits + this.workerIdBits; // 值为：17
        this.timestampLeftShift = this.sequenceBits + this.workerIdBits + this.dataCenterIdBits; // 值为：22
        this.sequenceMask = -1n ^ (-1n << this.sequenceBits); // 值为：4095
        this.lastTimestamp = -1n;
        //设置默认值,从环境变量取
        this.workerId = 1n;
        this.dataCenterId = 1n;
        this.sequence = 0n;
        if(this.workerId > this.maxWrokerId || this.workerId < 0) {
            thrownew Error('_workerId must max than 0 and small than maxWrokerId-[' + this.maxWrokerId + ']');
        }
        if(this.dataCenterId > this.maxDataCenterId || this.dataCenterId < 0) {
            thrownew Error('_dataCenterId must max than 0 and small than maxDataCenterId-[' + this.maxDataCenterId + ']');
        }
 
        this.workerId = BigInt(_workerId);
        this.dataCenterId = BigInt(_dataCenterId);
        this.sequence = BigInt(_sequence);
    }
    Snowflake.prototype.tilNextMillis = function(lastTimestamp) {
        var timestamp = this.timeGen();
        while(timestamp <= lastTimestamp) {
            timestamp = this.timeGen();
        }
        return BigInt(timestamp);
    };
    Snowflake.prototype.timeGen = function() {
        return BigInt(Date.now());
    };
    Snowflake.prototype.nextId = function() {
        var timestamp = this.timeGen();
        if(timestamp < this.lastTimestamp) {
            thrownew Error('Clock moved backwards. Refusing to generate id for ' +
                (this.lastTimestamp - timestamp));
        }
        if(this.lastTimestamp === timestamp) {
            this.sequence = (this.sequence + 1n) & this.sequenceMask;
            if(this.sequence === 0n) {
                timestamp = this.tilNextMillis(this.lastTimestamp);
            }
        } else {
            this.sequence = 0n;
        }
        this.lastTimestamp = timestamp;
        return((timestamp - this.twepoch) << this.timestampLeftShift) |
            (this.dataCenterId << this.dataCenterIdShift) |
            (this.workerId << this.workerIdShift) |
            this.sequence;
    };
    return Snowflake;
}());
 
console.log(new Snowflake(1n, 1n, 0n).nextId());
//1141531990672150528n

控制台输出1141531990672150528n为bigint格式, .toString()转为字符串格式即可

3、ES6使用

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
import bigInt from "big-integer";
 
const guid = () => {
 const Snowflake = /** @class */ (function() {
  function Snowflake(_workerId, _dataCenterId, _sequence) {
   // this.twepoch = 1288834974657;
   this.twepoch = 0;
   this.workerIdBits = 5;
   this.dataCenterIdBits = 5;
   this.maxWrokerId = -1 ^ (-1 << this.workerIdBits); // 值为：31
   this.maxDataCenterId = -1 ^ (-1 << this.dataCenterIdBits); // 值为：31
   this.sequenceBits = 12;
   this.workerIdShift = this.sequenceBits; // 值为：12
   this.dataCenterIdShift = this.sequenceBits + this.workerIdBits; // 值为：17
   this.timestampLeftShift = this.sequenceBits + this.workerIdBits + this.dataCenterIdBits; // 值为：22
   this.sequenceMask = -1 ^ (-1 << this.sequenceBits); // 值为：4095
   this.lastTimestamp = -1;
   //设置默认值,从环境变量取
   this.workerId = 1;
   this.dataCenterId = 1;
   this.sequence = 0;
   if (this.workerId > this.maxWrokerId || this.workerId < 0) {
    throw new Error(
     'config.worker_id must max than 0 and small than maxWrokerId-[' + this.maxWrokerId + ']'
    );
   }
   if (this.dataCenterId > this.maxDataCenterId || this.dataCenterId < 0) {
    throw new Error(
     'config.data_center_id must max than 0 and small than maxDataCenterId-[' +
      this.maxDataCenterId +
      ']'
    );
   }
   this.workerId = _workerId;
   this.dataCenterId = _dataCenterId;
   this.sequence = _sequence;
  }
  Snowflake.prototype.tilNextMillis = function(lastTimestamp) {
   var timestamp = this.timeGen();
   while (timestamp <= lastTimestamp) {
    timestamp = this.timeGen();
   }
   return timestamp;
  };
  Snowflake.prototype.timeGen = function() {
   //new Date().getTime() === Date.now()
   return Date.now();
  };
  Snowflake.prototype.nextId = function() {
   var timestamp = this.timeGen();
   if (timestamp < this.lastTimestamp) {
    throw new Error(
     'Clock moved backwards. Refusing to generate id for ' + (this.lastTimestamp - timestamp)
    );
   }
   if (this.lastTimestamp === timestamp) {
    this.sequence = (this.sequence + 1) & this.sequenceMask;
    if (this.sequence === 0) {
     timestamp = this.tilNextMillis(this.lastTimestamp);
    }
   } else {
    this.sequence = 0;
   }
   this.lastTimestamp = timestamp;
   var shiftNum =
    (this.dataCenterId << this.dataCenterIdShift) |
    (this.workerId << this.workerIdShift) |
    this.sequence; // dataCenterId:1,workerId:1,sequence:0 shiftNum:135168
   var nfirst = new bigInt(String(timestamp - this.twepoch), 10);
   nfirst = nfirst.shiftLeft(this.timestampLeftShift);
   var nnextId = nfirst.or(new bigInt(String(shiftNum), 10)).toString(10);
   return nnextId;
  };
  return Snowflake;
 })();
 
 return new Snowflake(1, 1, 0).nextId();
};

guid()即可调用

4、多次重复调用出现一样id的bug

?
1
2
3
4
5
6
7
8
9
10
11
12
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());
console.log(guid(), new Date().getTime());

Js Snowflake(雪花算法)生成随机ID的实现方法

修改如下

?
1
2
3
4
5
6
7
8
9
10
import SnowflakeId from "snowflake-id";
 
const guid = num => {
 const snowflake = new SnowflakeId();
 let arr = [];
 for (let i = 0; i < num; i++) {
  arr.push(snowflake.generate());
 }
 return num ? arr : snowflake.generate();
};

单个调用 guid()

n个调用 guid(n)

文档

到此这篇关于Js Snowflake(雪花算法)生成随机ID的实现方法的文章就介绍到这了,更多相关Js 雪花算法生成随机ID内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家！

原文链接：https://blog.csdn.net/qq_36658051/article/details/92981439

  • JS
  • 雪花算法

    • 延伸 · 阅读

    精彩推荐
    最近更新
    编辑推荐
    阅读排行
    热门标签
    格斗 　 原型 　 原型链 　 仿淘宝商城 　 jqeuryUI 　 网页对话框 　 样式规则 　 blockui 　 页面滚动 　 弹出窗 　 弹出提示 　 hidden 　 Hapi.js 　 无间断 　 对象构建 　 dialogArguments 　 随机显示 　 node应用 　 箭头函数 　 高级类型 　 Vuejs 　 JavaScript技术 　 并发语言 　 JavaScript优化 　 QRCanvas 　 JS库 　 Svelte 　 事件处理函数 　 名称冲突 　 当时时间 　
    © 2019-2023 服务器之家(www.zzvips.com) 版权所有关于我们联系我们版权申明网站地图