test-uuid-v5.js

var expect = require('chai').expect;
var UUID = require('./uuid-v5');
describe('When generating a uuid v5', function() {
  it('must generate the expected uuids from 3 examples on the web', function() {
    var testUrl = UUID.v5(UUID.URL, 'www.example.org');
    var testDns = UUID.v5(UUID.DNS, 'www.example.org');
    var testDns2 = UUID.v5(UUID.DNS, 'php.net');
    // see the examples here: http://jsfiddle.net/rexmac/F3pwA/
    expect(testDns).to.equal('74738ff5-5367-5958-9aee-98fffdcd1876');
    expect(testUrl).to.equal('abe19220-c90c-5288-b33a-58772250d428');

    // see https://servicecore.info/tools/uuid-generator/
    expect(testDns2).to.equal('c4a760a8-dbcf-5254-a0d9-6a4474bd1b62');
  });
});

uuid-v5.js

var crypto = require('crypto');

function _hash(version, hash) {
  return hash.substr(0,8) + '-' +
      hash.substr(8,4) + '-' +
      (version + hash.substr(13,3)) + '-' +
      ((parseInt(hash.substr(16, 2), 16) | 0x80) & 0xBF).toString(16) + hash.substr(18,2) + '-' +
      hash.substr(20,12);
}

function uuidV5(namespace, name) {
  var hexNm = namespace.replace(/[{}\-]/g, '');
  var bytesNm = new Buffer(hexNm, 'hex');
  var bytesName = new Buffer(name, 'utf8');
  var hash = crypto.createHash('sha1')
      .update(bytesNm).update(bytesName)
      .digest('hex');
  return _hash(5, hash);
}

module.exports = {
// well know uuid namespaces in rfc 1422
  DNS:  '6ba7b810-9dad-11d1-80b4-00c04fd430c8',
  URL:  '6ba7b811-9dad-11d1-80b4-00c04fd430c8',
  OID:  '6ba7b812-9dad-11d1-80b4-00c04fd430c8',
  X500: '6ba7b814-9dad-11d1-80b4-00c04fd430c8',

  v5: uuidV5
};