detect-port

What is detect-port?

The detect-port npm package is a utility for detecting available network ports on a machine. It is useful for scenarios where you need to find an open port to start a server or service.

What are detect-port's main functionalities?

Detecting an available port

This feature allows you to check if a specific port is available. If the port is occupied, it suggests an alternative available port.

const detect = require('detect-port');

const port = 3000;
detect(port, (err, _port) => {
  if (err) {
    console.log(err);
  }
  if (port === _port) {
    console.log(`port ${port} was not occupied`);
  } else {
    console.log(`port ${port} was occupied, try port ${_port}`);
  }
});

Promise-based port detection

This feature provides a promise-based approach to detect an available port, making it easier to integrate with modern JavaScript code that uses async/await.

const detect = require('detect-port');

const port = 3000;
detect(port).then(_port => {
  if (port === _port) {
    console.log(`port ${port} was not occupied`);
  } else {
    console.log(`port ${port} was occupied, try port ${_port}`);
  }
}).catch(err => {
  console.log(err);
});

Other packages similar to detect-port

portfinder

The portfinder package is another utility for finding open ports. It offers similar functionality to detect-port but includes additional features like specifying a range of ports to search within. It is also promise-based and has a more extensive API.

get-port

The get-port package is a lightweight utility for finding an available port. It is similar to detect-port but focuses on simplicity and ease of use. It is promise-based and allows specifying a preferred port or a range of ports.

README

detect-port

port detector

Installment

$ npm i detect-port -g

Quick Start

# detect port 80
$ detect -p 80

# or like this
$ detect --port 80

# will get result below
$ port: 80 was occupied, try port: 1024

# with verbose
$ detect --port 80 --verbose

# more help?
$ detect -h

Use As Module

var detect = require('detect-port');

/**
 * normal usage
 */

detect(port, function(error, _port) {

  if (port === _port) {
    console.log('port: %d was not occupied', port);
  } else {
    console.log('port: %d was occupied, try port: %d', port, _port);
  }
});

/**
 * use in co v3
 * for a yield syntax instead of callback function implement
 */

var co = require('co');

co(function *() {
  var _port = yield detect(port);

  if (port === _port) {
    console.log('port: %d was not occupied', port);
  } else {
    console.log('port: %d was occupied, try port: %d', port, _port);
  }
})();

/**
 * use as a promise
 */

var promisePort = detect(port);

promisePort.then(function(_port) {
  if (port === _port) {
    console.log('port: %d was not occupied', port);
  } else {
    console.log('port: %d was occupied, try port: %d', port, _port);
  }
});

Clone and Run test

# clone from git
$ git clone git://github.com/xudafeng/detect-port.git

$ cd detect-port

# install dependencies
$ make install

# test and coverage
$ make test

License

MIT

Copyright (c) 2015 xdf

Changelog

0.1.4 / 2015-08-24

• Support promise