Universally unique and cryptographically unpredictable URL-safe identifiers
npm install generate-safe-idA command line tool and Node.js library for generating globally unique and
cryptographically unpredictable identifiers.
Identifiers consist entirely of uppercase and lowercase letters (a-z, A-Z),
digits (0-9), hyphens ("-"), and underscores ("_"), making them safe in URLs
and other contexts.
Random UUIDs (UUIDv4) do not have enough entropy to be universally unique
(ironic, eh?). Random UUIDs have only 122 bits of entropy, which suggests
that a duplicate will occur after only 2^61 IDs. Additionally, some UUIDv4
implementations do not use a cryptographically strong random number generator.
This library generates 240-bit IDs using the Node.js crypto RNG, suggesting the
first duplicate will occur after generating 2^120 IDs. Based on the current
energy production of the human race, this threshold will be impossible to cross
for the foreseeable future.
Installation with npm:
``
$ npm install generate-safe-id
Using generate-safe-id from Node.js:
`
var generateSafeId = require('generate-safe-id');
var id = generateSafeId();
// id == "zVPkWyvgRW-7pSk0iRzEhdnPcnWfMRi-ZcaPxrHA"
`
Alternatively, this library can be used from the command line when installed
globally:
`
$ npm install -g generate-safe-id
$ generate-safe-id
teErzw09Am-Yq_ylT8gb3zBCbpnSWgeS-m_xv5-v
Use the -n flag to prevent the output from being terminated with a line break
(useful for scripting).
`
$ generate-safe-id -n
wiIVSSXbbnDp5NJ_x7Iu1VC2iF34WZRtt9fXh13C
Contact Tim McLean at [first name]@[first name][last name].net` (PGP key).
Note: this ID generator is not constant time (see issue #1).