pure-uuid

Pure-UUID

Pure JavaScript Based Universally Unique Identifier (UUID)

Abstract

This is a pure JavaScript and dependency-free library for the generation of DCE 1.1, ISO/IEC 11578:1996 and IETF RFC-4122 compliant Universally Unique Identifier (UUID). It supports DCE 1.1 variant UUIDs of version 1 (time and node based), version 3 (name based, MD5), version 4 (random number based) and version 5 (name based, SHA-1). It can be used in both Node.js based server and browser based client environments.

The essential points of this implementation (in contrast to the many others) are: First, although internally 32/64 bit unsigned integer arithmentic and MD5/SHA-1 digest algorithmic is required, this UUID implementation is fully self-contained and dependency-free. Second, this implementation wraps around either Uint8Array, Buffer or Array standard classes and this way tries to represent UUIDs as best as possible in the particular environment. Third, thanks to a Universal Module Definition (UMD) wrapper, this library works out-of-the-box in all important JavaScript run-time environments.

What is a UUID?

UUIDs are 128 bit numbers which are intended to have a high likelihood of uniqueness over space and time and are computationally difficult to guess. They are globally unique identifiers which can be locally generated without contacting a global registration authority. UUIDs are intended as unique identifiers for both mass tagging objects with an extremely short lifetime and to reliably identifying very persistent objects across a network.

UUID Binary Representation

According to the DCE 1.1, ISO/IEC 11578:1996 and IETF RFC-4122 standards, a DCE 1.1 variant UUID is a 128 bit number defined out of 7 fields, each field a multiple of an octet in size and stored in network byte order:

                                                    [4]
                                                   version
                                                 -->|  |<--
                                                    |  |
                                                    |  |  [16]
                [32]                      [16]      |  |time_hi
              time_low                  time_mid    | _and_version
    |<---------------------------->||<------------>||<------------>|
    | MSB                          ||              ||  |           |
    | /                            ||              ||  |           |
    |/                             ||              ||  |           |

    +------++------++------++------++------++------++------++------+~~
    |  15  ||  14  ||  13  ||  12  ||  11  ||  10  |####9  ||   8  |
    | MSO  ||      ||      ||      ||      ||      |####   ||      |
    +------++------++------++------++------++------++------++------+~~
    7654321076543210765432107654321076543210765432107654321076543210

  ~~+------++------++------++------++------++------++------++------+
    ##* 7  ||   6  ||   5  ||   4  ||   3  ||   2  ||   1  ||   0  |
    ##*    ||      ||      ||      ||      ||      ||      ||  LSO |
  ~~+------++------++------++------++------++------++------++------+
    7654321076543210765432107654321076543210765432107654321076543210

    | |    ||      ||                                             /|
    | |    ||      ||                                            / |
    | |    ||      ||                                          LSB |
    |<---->||<---->||<-------------------------------------------->|
    |clk_seq clk_seq                      node
    |_hi_res _low                         [48]
    |[5-6]    [8]
    | |
 -->| |<--
  variant
   [2-3]

An example of a UUID binary representation is the octet stream 0xF8 0x1D 0x4F 0xAE 0x7D 0xEC 0x11 0xD0 0xA7 0x65 0x00 0xA0 0xC9 0x1E 0x6B 0xF6.

UUID ASCII String Representation

According to the DCE 1.1, ISO/IEC 11578:1996 and IETF RFC-4122 standards, a DCE 1.1 variant UUID is represented as an ASCII string consisting of 8 hexadecimal digits followed by a hyphen, then three groups of 4 hexadecimal digits each followed by a hyphen, then 12 hexadecimal digits.

Getting Pure-UUID

$ npm install pure-uuid

Using Pure-UUID

• global environment:

var uuid = new UUID(3, "ns:URL", "http://example.com/");

• CommonJS environment:

var UUID = require("pure-uuid");
var uuid = new UUID(3, "ns:URL", "http://example.com/");

• AMD environment:

define(["pure-uuid"], function (UUID) {
    var uuid = new UUID(3, "ns:URL", "http://example.com/");
});

API

interface UUID {
    /*  making  */
    make(version: number, ...params: any[]): UUID;

    /*  parsing  */
    parse(str: string): UUID;

    /*  formatting  */
    format(type?: string): string;

    /*  formatting (alias)  */
    toString(type?: string): string;

    /*  sensible JSON serialization  */
    toJSON(): string;

    /*  importing  */
    import(arr: number[]): UUID;

    /*  exporting  */
    export(): number[];

    /*  byte-wise comparison  */
    compare(other: UUID): boolean;

    /*  equal check  */
    equal(other: UUID): boolean;

    /*  fold 1-4 times  */
    fold(k: number): number[];
}

export interface UUIDConstructor {
  /*  default construction  */
  new(): UUID;

  /*  parsing construction  */
  new(uuid: string): UUID;

  /*  making construction  */
  new(version: number): UUID;
  new(version: number, ns: string, data: string): UUID;
}

declare var UUID: UUIDConstructor;
export default UUID;

Examples

//  load a UUID
uuid = new UUID("0a300ee9-f9e4-5697-a51a-efc7fafaba67");

//  make a UUID version 1 (time and node based)
uuid = new UUID(1);

//  make a UUID version 3 (name-based, MD5)
uuid = new UUID(3, "ns:URL", "http://example.com/");

//  make a UUID version 4 (random number based)
uuid = new UUID(4);

//  make a UUID version 5 (name-based, SHA-1)
uuid = new UUID(5, "ns:URL", "http://example.com/");

//  format a UUID in standard format
str = uuid.format()
str = uuid.format("std")

//  format a UUID in Base16 format
str = uuid.format("b16")

//  format a UUID in ZeroMQ-Base85 format
str = uuid.format("z85")

License

Copyright © 2004-2023 Dr. Ralf S. Engelschall (http://engelschall.com/)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.