getport Build Status

Get an available TCP port

Usage

import { getPort } from "https://deno.land/x/getport/mod.ts";

const port = await getPort({}).catch((error: Error) => {
  throw error;
});

console.log(port); //=> fall back to a random port

Pass in a preferred port:

import { getPort } from "https://deno.land/x/getport/mod.ts";

const port = await getPort({ port: 3000 }).catch((error: Error) => {
  throw error;
});

console.log(port); //=> Will use 3000 if available, otherwise fall back to a random port

Pass in an array of preferred ports:

import { getPort } from "https://deno.land/x/getport/mod.ts";

const port = await getPort({ port: [3000, 3001, 3002] }).catch((error: Error) => {
  throw error;
});

console.log(port); //=> Will use any element in the preferred ports array if available, otherwise fall back to a random port

Use the makeRange() helper in case you need a port in a certain range:

import { getPort, makeRange } from "https://deno.land/x/getport/mod.ts";

const port = await getPort({ port: makeRange(3000, 3100) }).catch((error: Error) => {
  throw error;
});

console.log(port); //=> Will use any port from 3000 to 3100, otherwise fall back to a random port

API

getPort(options?)

Returns a Promise for a port number.

options

Type: object

port

Type: number | Iterable<number>

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

hostname

Type: string

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

makeRange(from, to)

Make a range of ports from…to.

Returns an Iterable for ports in the given range.

from

Type: number

First port of the range. Must be in the range 1024…65535.

to

Type: number

Last port of the range. Must be in the range 1024…65535 and must be greater than from.