find-free-port
v2.0.0
Published
find a free tcp port to listen locally
Downloads
55,567
Readme
find-free-port
Find free tcp port or pors to listen on. The definition of 'free' port is that connecting to this port and host ('localhost' by default) will not succeed, and thus 'free'.
Installation
npm install find-free-port --save
Examples
Find a free port to listen on that is >= 3000
var fp = require("find-free-port")
fp(3000, function(err, freePort){
});
Find a free port to listen on that is >= 3000 and < 3100
var fp = require("find-free-port")
fp(3000, 3100, function(err, freePort){
});
Find 3 free ports to listen on that is >= 3000 locally
var fp = require("find-free-port")
fp(3000, 3100, '127.0.0.1', 3, function(err, p1, p2, p3){
});
Find a free port that is >= 3000 and at host 192.168.100.1
var fp = require("find-free-port")
fp(3000, "192.168.100.1", function(err, freePort){
});
Promise
If the callback is omitted, then the call returns a Promise that resolve to a list of avaiable ports:
var fp = require("find-free-port")
fp(3000).then(([freep]) => {
console.log('found ' + freep);
}).catch((err)=>{
console.error(err);
});