Response Time Check using curl and nodejs

checkResponseTime.js

var exec = require('child_process').exec;
var url = process.argv[2];
var threshold = parseFloat(process.argv[3]);
var eventName;
var state;

var cmd = 'curl -o /dev/null -s -w %{time_total} ' + url;

console.log('running ' + cmd);
console.log('checking response time for ' + url + ' is below => ' + threshold);

exec(cmd, function(err, stdout, stderr){
    var responseTime;
    var state;

    responseTime = parseFloat( stdout.replace(',','.') );

    if ( !stdout || isNaN(responseTime) ) {
        state = 'failure';
    } else {
        state = (responseTime >= threshold) ? 'failure' : 'success';
    }

    console.log( JSON.stringify({ state: state, data: { responseTime: String(responseTime) } }) );
});