get-port

Get an available TCP port

Install

$ npm install get-port

Usage

const getPort = require('get-port');

(async () => {
	console.log(await getPort());
	//=> 51402
})();

Pass in a preferred port:

(async () => {
	console.log(await getPort({port: 3000}));
	// Will use 3000 if available, otherwise fall back to a random port
})();

Pass in an array of preferred ports:

(async () => {
	console.log(await getPort({port: [3000, 3001, 3002]}));
	// Will use any element in the preferred ports array if available, otherwise fall back to a random port
})();

API

getPort([options])

Returns a Promise for a port number.

options

Type: Object

port

Type: number | number[]

A preferred port or an array of preferred ports to use.

host

Type: string

The host on which port resolution should be performed. Can be either an IPv4 or IPv6 address.

Beware

There is a very tiny chance of a race condition if another service starts using the same port number as you in between the time you get the port number and you actually start using it.

get-port-cli - CLI for this module

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