uuidjs
https://github.com/uuidjs/uuid/
1. Install
npm install uuid
2. Create a UUID (ES6 module syntax)
import { v4 as uuidv4 } from 'uuid';
uuidv4(); // ⇨ '9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d'
... or using CommonJS syntax:
const { v4: uuidv4 } = require('uuid');
uuidv4(); // ⇨ '1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed'
API
uuid.NIL
The nil UUID string (all zeros).
Example:
import { NIL as NIL_UUID } from 'uuid';
NIL_UUID; // ⇨ '00000000-0000-0000-0000-000000000000'
uuid.parse(str)
Convert UUID string to array of bytes
| A valid UUID |
returns |
|
throws |
|
Note: Ordering of values in the byte arrays used by parse()
and stringify()
follows the left ↠ right order of hex-pairs in UUID strings. As shown in the example below.
Example:
import { parse as uuidParse } from 'uuid';
// Parse a UUID
const bytes = uuidParse('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b');
// Convert to hex strings to show byte order (for documentation purposes)
[...bytes].map((v) => v.toString(16).padStart(2, '0')); // ⇨
// [
// '6e', 'c0', 'bd', '7f',
// '11', 'c0', '43', 'da',
// '97', '5e', '2a', '8a',
// 'd9', 'eb', 'ae', '0b'
// ]
uuid.stringify(arr[, offset])
Convert array of bytes to UUID string
|
|
[ |
|
returns |
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throws |
|
Note: Ordering of values in the byte arrays used by parse()
and stringify()
follows the left ↠ right order of hex-pairs in UUID strings. As shown in the example below.
Example:
import { stringify as uuidStringify } from 'uuid';
const uuidBytes = [
0x6e, 0xc0, 0xbd, 0x7f, 0x11, 0xc0, 0x43, 0xda, 0x97, 0x5e, 0x2a, 0x8a, 0xd9, 0xeb, 0xae, 0x0b,
];
uuidStringify(uuidBytes); // ⇨ '6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'
uuid.v1([options[, buffer[, offset]]])
Create an RFC version 1 (timestamp) UUID
[ |
|
[ | RFC "node" field as an |
[ | RFC "clock sequence" as a |
[ | RFC "timestamp" field ( |
[ | RFC "timestamp" field ( |
[ |
|
[ | Alternative to |
[ |
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[ |
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returns | UUID |
throws |
|
Note: The default node id (the last 12 digits in the UUID) is generated once, randomly, on process startup, and then remains unchanged for the duration of the process.
Note: options.random
and options.rng
are only meaningful on the very first call to v1()
, where they may be passed to initialize the internal node
and clockseq
fields.
Example:
import { v1 as uuidv1 } from 'uuid';
uuidv1(); // ⇨ '2c5ea4c0-4067-11e9-8bad-9b1deb4d3b7d'
Example using options
:
import { v1 as uuidv1 } from 'uuid';
const v1options = {
node: [0x01, 0x23, 0x45, 0x67, 0x89, 0xab],
clockseq: 0x1234,
msecs: new Date('2011-11-01').getTime(),
nsecs: 5678,
};
uuidv1(v1options); // ⇨ '710b962e-041c-11e1-9234-0123456789ab'
uuid.v3(name, namespace[, buffer[, offset]])
Create an RFC version 3 (namespace w/ MD5) UUID
API is identical to v5()
, but uses "v3" instead.
⚠️ Note: Per the RFC, "If backward compatibility is not an issue, SHA-1 [Version 5] is preferred."
uuid.v4([options[, buffer[, offset]]])
Create an RFC version 4 (random) UUID
[ |
|
[ |
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[ | Alternative to |
[ |
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[ |
|
returns | UUID |
Example:
import { v4 as uuidv4 } from 'uuid';
uuidv4(); // ⇨ '1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed'
Example using predefined random
values:
import { v4 as uuidv4 } from 'uuid';
const v4options = {
random: [
0x10, 0x91, 0x56, 0xbe, 0xc4, 0xfb, 0xc1, 0xea, 0x71, 0xb4, 0xef, 0xe1, 0x67, 0x1c, 0x58, 0x36,
],
};
uuidv4(v4options); // ⇨ '109156be-c4fb-41ea-b1b4-efe1671c5836'
uuid.v5(name, namespace[, buffer[, offset]])
Create an RFC version 5 (namespace w/ SHA-1) UUID
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[ |
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[ |
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returns | UUID |
Note: The RFC DNS
and URL
namespaces are available as v5.DNS
and v5.URL
.
Example with custom namespace:
import { v5 as uuidv5 } from 'uuid';
// Define a custom namespace. Readers, create your own using something like
// https://www.uuidgenerator.net/
const MY_NAMESPACE = '1b671a64-40d5-491e-99b0-da01ff1f3341';
uuidv5('Hello, World!', MY_NAMESPACE); // ⇨ '630eb68f-e0fa-5ecc-887a-7c7a62614681'
Example with RFC URL
namespace:
import { v5 as uuidv5 } from 'uuid';
uuidv5('https://www.w3.org/', uuidv5.URL); // ⇨ 'c106a26a-21bb-5538-8bf2-57095d1976c1'
uuid.validate(str)
Test a string to see if it is a valid UUID
|
|
returns |
|
Example:
import { validate as uuidValidate } from 'uuid';
uuidValidate('not a UUID'); // ⇨ false
uuidValidate('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ true
Using validate
and version
together it is possible to do per-version validation, e.g. validate for only v4 UUIds.
import { version as uuidVersion } from 'uuid';
import { validate as uuidValidate } from 'uuid';
function uuidValidateV4(uuid) {
return uuidValidate(uuid) && uuidVersion(uuid) === 4;
}
const v1Uuid = 'd9428888-122b-11e1-b85c-61cd3cbb3210';
const v4Uuid = '109156be-c4fb-41ea-b1b4-efe1671c5836';
uuidValidateV4(v4Uuid); // ⇨ true
uuidValidateV4(v1Uuid); // ⇨ false
uuid.version(str)
Detect RFC version of a UUID
| A valid UUID |
returns |
|
throws |
|
Example:
import { version as uuidVersion } from 'uuid';
uuidVersion('45637ec4-c85f-11ea-87d0-0242ac130003'); // ⇨ 1
uuidVersion('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ 4
Command Line
UUIDs can be generated from the command line using uuid
.
$ npx uuid
ddeb27fb-d9a0-4624-be4d-4615062daed4
The default is to generate version 4 UUIDS, however the other versions are supported. Type uuid --help
for details:
$ npx uuid --help
Usage:
uuid
uuid v1
uuid v3 <name> <namespace uuid>
uuid v4
uuid v5 <name> <namespace uuid>
uuid --help
Note: <namespace uuid> may be "URL" or "DNS" to use the corresponding UUIDs
defined by RFC4122
ECMAScript Modules
This library comes with ECMAScript Modules (ESM) support for Node.js versions that support it (example) as well as bundlers like rollup.js (example) and webpack (example) (targeting both, Node.js and browser environments).
import { v4 as uuidv4 } from 'uuid';
uuidv4(); // ⇨ '1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed'
To run the examples you must first create a dist build of this library in the module root: