is-port-available (nodejs)

``(async) isPortAvailable()` : Will test the requested port, resolving the returned Promise with `true`, when port IS AVAILABLE, and `false` when NOT AVAILABLE.
> NOTE: When port is NOT AVAILABLE, the fail reason (err.code | err) can be checked reading `isPortAvailable.lastError` property (wich is reset automatically before each call to isPortAvailable)

$3

`isPortAvailable( port )` (function) => Expects an integer, and returns a Promise that resolves in true|false

`isPortAvailable.lastError` (string) => Contains the last call error (EADDRINUSE, EACCES...)

$3

Use npm to install the module :
`$ npm install --save is-port-available`


NPM Package Page

$3


Example of a simple port avaiability test via `Promise.then()`:
`javascript
const isPortAvailable = require('is-port-available');

var port = 80;
isPortAvailable(port).then( status =>{
if(status) console.log('Port ' + port + ' IS available!');
else{
console.log('Port ' + port + ' IS NOT available!');
console.log('Reason : ' + isPortAvailable.lastError);
}
});
`
Example Using `await` inside an `async` self invoking function :
`javascript
const isPortAvailable = require('is-port-available');

(async function(){
var port = 80;
var status = await isPortAvailable(port);

if(status) console.log('Port ' + port + ' IS available!');
else{
console.log('Port ' + port + ' IS NOT available!');
console.log('Reason : ' + isPortAvailable.lastError);
}

})()
``

Licence

GPL