Get an available TCP port to listen

Install package:

npm i get-port-please

// ESM
import {
  getPort,
  checkPort,
  getRandomPort,
  waitForPort,
  getSocketAddress,
  isSocketSupported,
  cleanSocket
} from "get-port-please";

// CommonJS
const {
  getPort,
  checkPort,
  getRandomPort,
  waitForPort,
  getSocketAddress,
  isSocketSupported,
  cleanSocket
} = require("get-port-please");

getPort(options: GetPortOptions): Promise<number>;
checkPort(port: number, host?: string): Promise<number | false>
waitForPort(port: number, options): Promise<number | false>

Try sequence is: port > ports > random

interface GetPortOptions {
  name?: string;

  random?: boolean;
  port?: number;
  portRange?: [fromInclusive: number, toInclusive: number];
  ports?: number[];
  host?: string;

  memoDir?: string;
  memoName?: string;
}

Unique name for port memorizing. Default is default.

If enabled, port and ports will be ignored. Default is false.

First port to check. Default is process.env.PORT || 3000

Extended ports to check.

Extended port range to check.

The range's start and end are inclusive, i.e. it is [start, end] in the mathematical notion. Reversed port ranges are not supported. If start > end, then an empty range will be returned.

Alternative port range to check as fallback when none of the ports are available.

The range's start and end are inclusive, i.e. it is [start, end] in the mathematical notion. Reversed port ranges are not supported. If start > end, then an empty range will be returned.

The default range is [3000, 3100] (only when port is unspecified).

The host to check. Default is process.env.HOST otherwise all available hosts will be checked.

MIT