UUIDs (Universally Unique IDentifier), also known as GUIDs (Globally Unique IDentifier), according to RFC 4122, are identifiers designed to provide certain uniqueness guarantees.
While it is possible to implement RFC-compliant UUIDs in a few lines of JavaScript code (e.g., see @broofa’s answer, below) there are several common pitfalls:
- Invalid id format (UUIDs must be of the form “
xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx“, where x is one of [0-9, a-f] M is one of [1-5], and N is [8, 9, a, or b] - Use of a low-quality source of randomness (such as
Math.random)
Thus, developers writing code for production environments are encouraged to use a rigorous, well-maintained implementation such as the uuid module.
