uuid
Simple, fast generation of RFC4122 UUIDS.
Features:
- Support for version 1, 3, 4 and 5 UUIDs
- Cross-platform
- Uses cryptographically-strong random number APIs (when available)
- Zero-dependency, small footprint (... but not this small)
[Deprecation warning: The use of require('uuid')
is deprecated and will not be
supported after version 3.x of this module. Instead, use require('uuid/[v1|v3|v4|v5]')
as shown in the examples below.]
Quickstart - CommonJS (Recommended)
npm install uuid
Then generate your uuid version of choice ...
Version 1 (timestamp):
const uuidv1 = require('uuid/v1');
uuidv1(); // ⇨ '3b99e3e0-7598-11e8-90be-95472fb3ecbd'
Version 3 (namespace):
const uuidv3 = require('uuid/v3');
// ... using predefined DNS namespace (for domain names)
uuidv3('hello.example.com', uuidv3.DNS); // ⇨ '9125a8dc-52ee-365b-a5aa-81b0b3681cf6'
// ... using predefined URL namespace (for, well, URLs)
uuidv3('http://example.com/hello', uuidv3.URL); // ⇨ 'c6235813-3ba4-3801-ae84-e0a6ebb7d138'
// ... using a custom namespace
//
// Note: Custom namespaces should be a UUID string specific to your application!
// E.g. the one here was generated using this modules `uuid` CLI.
const MY_NAMESPACE = '1b671a64-40d5-491e-99b0-da01ff1f3341';
uuidv3('Hello, World!', MY_NAMESPACE); // ⇨ 'e8b5a51d-11c8-3310-a6ab-367563f20686'
Version 4 (random):
const uuidv4 = require('uuid/v4');
uuidv4(); // ⇨ '3a017fc5-4f50-4db9-b0ce-4547ba0a1bfd'
Version 5 (namespace):
const uuidv5 = require('uuid/v5');
// ... using predefined DNS namespace (for domain names)
uuidv5('hello.example.com', uuidv5.DNS); // ⇨ 'fdda765f-fc57-5604-a269-52a7df8164ec'
// ... using predefined URL namespace (for, well, URLs)
uuidv5('http://example.com/hello', uuidv5.URL); // ⇨ '3bbcee75-cecc-5b56-8031-b6641c1ed1f1'
// ... using a custom namespace
//
// Note: Custom namespaces should be a UUID string specific to your application!
// E.g. the one here was generated using this modules `uuid` CLI.
const MY_NAMESPACE = '1b671a64-40d5-491e-99b0-da01ff1f3341';
uuidv5('Hello, World!', MY_NAMESPACE); // ⇨ '630eb68f-e0fa-5ecc-887a-7c7a62614681'
Quickstart - Browser-ready Versions
Browser-ready versions of this module are available via wzrd.in.
For version 1 uuids:
<script src="http://wzrd.in/standalone/uuid%2Fv1@latest"></script>
<script>
uuidv1(); // -> v1 UUID
</script>
For version 3 uuids:
<script src="http://wzrd.in/standalone/uuid%2Fv3@latest"></script>
<script>
uuidv3('http://example.com/hello', uuidv3.URL); // -> v3 UUID
</script>
For version 4 uuids:
<script src="http://wzrd.in/standalone/uuid%2Fv4@latest"></script>
<script>
uuidv4(); // -> v4 UUID
</script>
For version 5 uuids:
<script src="http://wzrd.in/standalone/uuid%2Fv5@latest"></script>
<script>
uuidv5('http://example.com/hello', uuidv5.URL); // -> v5 UUID
</script>
API
Version 1
const uuidv1 = require('uuid/v1');
// Incantations
uuidv1();
uuidv1(options);
uuidv1(options, buffer, offset);
Generate and return a RFC4122 v1 (timestamp-based) UUID.
-
options
- (Object) Optional uuid state to apply. Properties may include:node
- (Array) Node id as Array of 6 bytes (per 4.1.6). Default: Randomly generated ID. See note 1.clockseq
- (Number between 0 - 0x3fff) RFC clock sequence. Default: An internally maintained clockseq is used.msecs
- (Number) Time in milliseconds since unix Epoch. Default: The current time is used.nsecs
- (Number between 0-9999) additional time, in 100-nanosecond units. Ignored ifmsecs
is unspecified. Default: internal uuid counter is used, as per 4.2.1.2.
-
buffer
- (Array | Buffer) Array or buffer where UUID bytes are to be written. -
offset
- (Number) Starting index inbuffer
at which to begin writing.
Returns buffer
, if specified, otherwise the string form of the UUID
Note: The id is generated guaranteed to stay constant for the lifetime of the current JS runtime. (Future versions of this module may use persistent storage mechanisms to extend this guarantee.)
Example: Generate string UUID with fully-specified options
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'
Example: In-place generation of two binary IDs
// Generate two ids in an array
const arr = new Array();
uuidv1(null, arr, 0); // ⇨ [ 59, 155, 106, 128, 117, 152, 17, 232, 146, 52, 149, 71, 47, 179, 236, 189 ]
uuidv1(null, arr, 16); // ⇨ [ 59, 155, 106, 128, 117, 152, 17, 232, 146, 52, 149, 71, 47, 179, 236, 189, 59, 155, 145, 144, 117, 152, 17, 232, 146, 52, 149, 71, 47, 179, 236, 189 ]
Version 3
const uuidv3 = require('uuid/v3');
// Incantations
uuidv3(name, namespace);
uuidv3(name, namespace, buffer);
uuidv3(name, namespace, buffer, offset);
Generate and return a RFC4122 v3 UUID.
name
- (String | Array[]) "name" to create UUID withnamespace
- (String | Array[]) "namespace" UUID either as a String or Array[16] of byte valuesbuffer
- (Array | Buffer) Array or buffer where UUID bytes are to be written.offset
- (Number) Starting index inbuffer
at which to begin writing. Default = 0
Returns buffer
, if specified, otherwise the string form of the UUID
Example:
uuidv3('hello world', MY_NAMESPACE); // ⇨ '042ffd34-d989-321c-ad06-f60826172424'
Version 4
const uuidv4 = require('uuid/v4')
// Incantations
uuidv4();
uuidv4(options);
uuidv4(options, buffer, offset);
Generate and return a RFC4122 v4 UUID.
options
- (Object) Optional uuid state to apply. Properties may include:random
- (Number[16]) Array of 16 numbers (0-255) to use in place of randomly generated valuesrng
- (Function) Random # generator function that returns an Array[16] of byte values (0-255)
buffer
- (Array | Buffer) Array or buffer where UUID bytes are to be written.offset
- (Number) Starting index inbuffer
at which to begin writing.
Returns buffer
, if specified, otherwise the string form of the UUID
Example: Generate string UUID with predefined random
values
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'
Example: Generate two IDs in a single buffer
const buffer = new Array();
uuidv4(null, buffer, 0); // ⇨ [ 202, 18, 44, 182, 222, 65, 71, 82, 164, 80, 208, 169, 173, 93, 252, 13 ]
uuidv4(null, buffer, 16); // ⇨ [ 202, 18, 44, 182, 222, 65, 71, 82, 164, 80, 208, 169, 173, 93, 252, 13, 243, 221, 205, 191, 130, 146, 75, 199, 146, 71, 96, 195, 45, 156, 124, 9 ]
Version 5
const uuidv5 = require('uuid/v5');
// Incantations
uuidv5(name, namespace);
uuidv5(name, namespace, buffer);
uuidv5(name, namespace, buffer, offset);
Generate and return a RFC4122 v5 UUID.
name
- (String | Array[]) "name" to create UUID withnamespace
- (String | Array[]) "namespace" UUID either as a String or Array[16] of byte valuesbuffer
- (Array | Buffer) Array or buffer where UUID bytes are to be written.offset
- (Number) Starting index inbuffer
at which to begin writing. Default = 0
Returns buffer
, if specified, otherwise the string form of the UUID
Example:
uuidv5('hello world', MY_NAMESPACE); // ⇨ '9f282611-e0fd-5650-8953-89c8e342da0b'
Command Line
UUIDs can be generated from the command line with the uuid
command.
$ uuid
ddeb27fb-d9a0-4624-be4d-4615062daed4
$ uuid v1
02d37060-d446-11e7-a9fa-7bdae751ebe1
Type uuid --help
for usage details
Testing
npm test
Markdown generated from README_js.md by