cuid

What is cuid?

The 'cuid' npm package is a library for generating collision-resistant unique identifiers optimized for horizontal scaling and performance. It is designed to be simple, fast, and reliable, making it suitable for use in distributed systems and databases.

What are cuid's main functionalities?

Generate a CUID

This feature allows you to generate a new CUID. The generated ID is a string that is guaranteed to be unique, making it ideal for use as a primary key in databases or as a unique identifier in distributed systems.

const cuid = require('cuid');
const id = cuid();
console.log(id);

Generate a Slug

This feature generates a shorter, URL-friendly version of a CUID, known as a slug. Slugs are useful for creating human-readable URLs or identifiers that need to be shorter than a full CUID.

const cuid = require('cuid');
const slug = cuid.slug();
console.log(slug);

Check if a String is a CUID

This feature allows you to check if a given string is a valid CUID. It returns a boolean value indicating whether the string conforms to the CUID format.

const cuid = require('cuid');
const isCuid = cuid.isCuid('cixl4bq9k0000mh3ea0000001');
console.log(isCuid);

Check if a String is a Slug

This feature allows you to check if a given string is a valid CUID slug. It returns a boolean value indicating whether the string conforms to the slug format.

const cuid = require('cuid');
const isSlug = cuid.isSlug('cixl4bq');
console.log(isSlug);

Other packages similar to cuid

uuid

The 'uuid' package is a popular library for generating universally unique identifiers (UUIDs). Unlike CUIDs, UUIDs are standardized and widely used across different systems and platforms. UUIDs are typically longer than CUIDs and are not as human-readable.

nanoid

The 'nanoid' package is a library for generating unique, URL-friendly IDs. It is similar to CUID in that it focuses on performance and collision resistance, but it generates shorter IDs by default. Nanoid is also highly customizable, allowing you to specify the alphabet and length of the generated IDs.

shortid

The 'shortid' package is another library for generating short, unique IDs. It is designed to be simple and fast, similar to CUID. However, 'shortid' is no longer maintained and has been deprecated in favor of 'nanoid'.

README

CUID

Collision-resistant client-side UID generator safe for element IDs and server-side lookups.

.cuid() returns a short random string with some collision-busting measures. Safe to use as HTML element ID's, and unique server-side record lookups.

Example

ch72gsb320000udocl363

Broken down

** c - h72gsb32 - 0000 - udoc - l363 **

The groups, in order, are:

• 'c' - identifies this as a cuid, and allows you to use it in html entity ids. The fixed value helps keep the ids sequential.
• timestamp
• counter - a single process might generate the same random string. The weaker the pseudo-random source, the higher the probability. That problem gets worse as processors get faster. The counter will roll over if the value gets too big.
• Client fingerprint
• Math.random()

Fingerprints

In browsers, the first chars are obtained from the user agent string (which is fairly unique), and the supported mimeTypes (which is also fairly unique, except for IE, which always returns 0). That string is concatenated with a count of variables in the global scope (which is also fairly unique), and the result is trimmed to 4 chars.

In node, the first two chars are extracted from the process.pid. The next two chars are extracted from the hostname.