miguelmota / is-valid-hostname

Validate hostname in JavaScript based on RFC-1123

is-valid-hostname

Validate hostname in JavaScript based on RFC-1123.

Demo

https://lab.miguelmota.com/is-valid-hostname

Install

npm install is-valid-hostname

Usage

const isValidHostname = require('is-valid-hostname')

isValidHostname('localhost') // true
isValidHostname('example.com') // true
isValidHostname('foo.example.com') // true
isValidHostname('bar.foo.example.com') // true
isValidHostname('exa-mple.co.uk') // true
isValidHostname('xn--80ak6aa92e.com') // true
isValidHostname('9gag.com') // true
isValidHostname('8.8.8.8') // true
isValidHostname('127.0.0.1') // true
isValidHostname('exa_mple.com') // false
isValidHostname('-example.com') // false
isValidHostname('example.com:3000') // false
isValidHostname('8.8.8.8:3000') // false

View more examples.

Test

npm test

FAQ

• Q: Why are numbers allowed in top-level domain?

  • A: Numbers in TLD are allowed under RFC-1123. See this answer for more information.

License

MIT

is-valid-hostname's Issues

`package.json` is missing a reference to the TypeScript typings

Currently, the TypeScript compiler can't find the typings included with this library without users manually referencing them (see #5).

To allow the compiler to find these typings and associate them with the main module, we just need to add

"types": "types/index.d.ts",

to package.json. 🙂

All-numeric hostnames should not be valid

Currently an all-numeric hostname like 10.10.10.10 returns true.

This should be false, per RFC 3696.

More information here: https://serverfault.com/questions/638260/is-it-valid-for-a-hostname-to-start-with-a-digit

[Feature request] TypeScript type definitions

Would be super useful to have these, either as part of the library itself, or on DefinitelyTyped. 🙂

There actually already seem to be some for your other library is-valid-domain: https://www.npmjs.com/package/@types/is-valid-domain

How to import types?

Hi @miguelmota!

First of all thank you for this amazing package. I ran up against an issue of importing the package into a typescript project.
The compiler tells the following

Could not find a declaration file for module 'is-valid-hostname'. '/home/daniel/danielproject/node_modules/is-valid-hostname/index.js' implicitly has an 'any' type.
  Try `npm i --save-dev @types/is-valid-hostname` if it exists or add a new declaration (.d.ts) file containing `declare module 'is-valid-hostname';

I've tried to add your types both in compilerOptions.typeRoots and compilerOptions.paths like that

"compilerOptions": {
  "typeRoots": [
    "node_modules/@types",
    "node_modules/is-valid-hostname/types/*"
  ],
}

"compilerOptions": {
  "paths": {
    "*": [
      "node_modules/*",
      "node_modules/is-valid-hostname/types/*"
    ]
  },
}

I will be very grateful if you can help me