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uuid Build Status

browser support

Simple, fast generation of RFC4122 UUIDS.

Features:

Getting Started

Install it in your browser:

<script src="uuid.js"></script>

Or in node.js:

npm install uuid
var uuid = require('uuid');

// Generate a v1 (time-based) id
uuid.v1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a'

// Generate a v4 (random) id
uuid.v4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'

API

uuid.v1([options [, buffer [, offset]]])

Generate and return a RFC4122 v1 (timestamp-based) UUID.

Returns buffer, if specified, otherwise the string form of the UUID

Notes:

  1. The randomly generated node id is only 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

uuid.v1({
  node: [0x01, 0x23, 0x45, 0x67, 0x89, 0xab],
  clockseq: 0x1234,
  msecs: new Date('2011-11-01').getTime(),
  nsecs: 5678
});   // -> "710b962e-041c-11e1-9234-0123456789ab"

Example: In-place generation of two binary IDs

// Generate two ids in an array
var arr = new Array(32); // -> []
uuid.v1(null, arr, 0);   // -> [02 a2 ce 90 14 32 11 e1 85 58 0b 48 8e 4f c1 15]
uuid.v1(null, arr, 16);  // -> [02 a2 ce 90 14 32 11 e1 85 58 0b 48 8e 4f c1 15 02 a3 1c b0 14 32 11 e1 85 58 0b 48 8e 4f c1 15]

// Optionally use uuid.unparse() to get stringify the ids
uuid.unparse(buffer);    // -> '02a2ce90-1432-11e1-8558-0b488e4fc115'
uuid.unparse(buffer, 16) // -> '02a31cb0-1432-11e1-8558-0b488e4fc115'

uuid.v4([options [, buffer [, offset]]])

Generate and return a RFC4122 v4 UUID.

Returns buffer, if specified, otherwise the string form of the UUID

Example: Generate string UUID with fully-specified options

uuid.v4({
  random: [
    0x10, 0x91, 0x56, 0xbe, 0xc4, 0xfb, 0xc1, 0xea,
    0x71, 0xb4, 0xef, 0xe1, 0x67, 0x1c, 0x58, 0x36
  ]
});
// -> "109156be-c4fb-41ea-b1b4-efe1671c5836"

Example: Generate two IDs in a single buffer

var buffer = new Array(32); // (or 'new Buffer' in node.js)
uuid.v4(null, buffer, 0);
uuid.v4(null, buffer, 16);

uuid.parse(id[, buffer[, offset]])

uuid.unparse(buffer[, offset])

Parse and unparse UUIDs

Example parsing and unparsing a UUID string

var bytes = uuid.parse('797ff043-11eb-11e1-80d6-510998755d10'); // -> <Buffer 79 7f f0 43 11 eb 11 e1 80 d6 51 09 98 75 5d 10>
var string = uuid.unparse(bytes); // -> '797ff043-11eb-11e1-80d6-510998755d10'

uuid.noConflict()

(Browsers only) Set uuid property back to it’s previous value.

Returns the uuid object.

Example:

var myUuid = uuid.noConflict();
myUuid.v1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a'

Deprecated APIs

Support for the following v1.2 APIs is available in v1.3, but is deprecated and will be removed in the next major version.

uuid([format [, buffer [, offset]]])

uuid() has become uuid.v4(), and the format argument is now implicit in the buffer argument. (i.e. if you specify a buffer, the format is assumed to be binary).

Testing

In node.js

> cd test
> node test.js

In Browser

open test/test.html

Benchmarking

Requires node.js

cd benchmark/
npm install
node benchmark.js

For a more complete discussion of uuid performance, please see the benchmark/README.md file, and the benchmark wiki

For browser performance checkout the JSPerf tests.

Release notes

2.0.0

1.4.0

1.3.2

1.3.0