node-portfinder

nstallation

  $ [sudo] npm install portfinder

 

Usage

var portfinder = require('portfinder');

  portfinder.getPort(function (err, port) {

    //

    // `port` is guaranteed to be a free port

    // in this scope.

    //

  });

Promise形式

const portfinder = require('portfinder');

  portfinder.getPortPromise()

    .then((port) => {

        //

        // `port` is guaranteed to be a free port

        // in this scope.

        //

    })

    .catch((err) => {

        //

        // Could not get a free port, `err` contains the reason.

        //

    });

Ports search scope

By default portfinder will start searching from 8000 and scan until maximum port number (65535) is reached.

You can change this globally by setting:

portfinder.basePort = 3000;    // default: 8000

portfinder.highestPort = 3333; // default: 65535

默认端口从8000扫描到65535，上面两个方法可以i实现自定义扫描范围

or by passing optional options object on each invocation:

portfinder.getPort({

    port: 3000,    // minimum port

    stopPort: 3333 // maximum port

}, callback);