parse-domain - a very solid lightweight library
npm install parse-domain
const { fromUrl, parseDomain } = require("parse-domain");
Example 1
parseDomain(fromUrl("http://www.example.com/12xy45"))
{ type: 'LISTED',
hostname: 'www.example.com',
labels: [ 'www', 'example', 'com' ],
icann:
{ subDomains: [ 'www' ],
domain: 'example',
topLevelDomains: [ 'com' ] },
subDomains: [ 'www' ],
domain: 'example',
topLevelDomains: [ 'com' ] }
Example 2
parseDomain(fromUrl("http://subsub.sub.test.ExAmPlE.coM/12xy45"))
{ type: 'LISTED',
hostname: 'subsub.sub.test.example.com',
labels: [ 'subsub', 'sub', 'test', 'example', 'com' ],
icann:
{ subDomains: [ 'subsub', 'sub', 'test' ],
domain: 'example',
topLevelDomains: [ 'com' ] },
subDomains: [ 'subsub', 'sub', 'test' ],
domain: 'example',
topLevelDomains: [ 'com' ] }
Why?
Depending on the use case and volume I strongly recommend against solving this problem yourself using regex or other string manipulation means. The core of this problem is that you need to know all the gtld and cctld suffixes to properly parse url strings into domain and subdomains, these suffixes are regularly updated. This is a solved problem and not one you want to solve yourself (unless you are google or something). Unless you need the hostname or domain name in a pinch don't try and parse your way out of this one.