Introduction to Detect-port

Detect-port is a powerful tool for identifying available ports on a machine, ensuring that your applications run smoothly without port conflicts. This guide provides comprehensive examples of its API along with code snippets.

Installation

npm install detect-port

Basic Usage

Check the availability of a specific 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}`);
   }
});

Using Promises

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

(async () => {
  try {
    const _port = await detect(3000);
    console.log(`port 3000 was not occupied`);
  } catch (err) {
    console.log(err);
  }
})();

Customized Port Range Detection

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

const portRange = [3000, 3005];

(async () => {
  for (let port of portRange) {
    try {
      const _port = await detect(port);
      if (port === _port) {
        console.log(`port ${port} was not occupied`);
        break;
      }
    } catch (err) {
      console.log(err);
    }
  }
})();

Detect-port in an Application

Below is an example of an application using detect-port to find an available port to run an Express server:

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

(async () => {
  try {
    const port = await detect(3000);
    app.listen(port, () => {
      console.log(`Server is running on port ${port}`);
    });
  } catch (err) {
    console.log(err);
  }
})();

Using detect-port ensures that your application avoids common port conflicts, improving the reliability and user experience.

Conclusion

Detect-port is a crucial tool for developers aiming to ensure reliable port management in their applications. Whether you prefer callbacks or promises, detect-port has you covered. Implement it today for more robust and conflict-free executions.