check whether a tcp server could be connected
npm install is-tcp-on``bash`
npm i is-tcp-on
`javascript``
var isTcpOn = require('is-tcp-on');
isTcpOn({
port: 80,
host: '127.0.0.1',
timeout: 1000 // optional, default is 1000ms
})
.then(function () {
// tcp server exists
}, function () {
// can not connect to this tcp server
});