check response time with curl and nodejs

checkResponseTime.js

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

var cmd = 'c:\\theeye\\theeyecore\\mingw64\\bin\\curl.exe -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,state;

    responseTime=parseFloat(stdout);

    if ( !stdout || isNaN(responseTime) ) {
        state='failure';
        event='command_failure'; // aca podemos asumir fallo del comando porque no devolvio el valor numerico esperado
    } else {
        state=(responseTime>=threshold) ? 'failure' : 'success';
        event=state; // para que disparece el evento failure o success. si se pone otra cosa no dispara evento
    }

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