lib/osutils.js

var _os = require('os');

window.platform = function(){
    return process.platform;
}

window.cpuCount = function(){
    return _os.cpus().length;
}

window.sysUptime = function(){
    //seconds
    return _os.uptime();
}

window.processUptime = function(){
    //seconds
    return process.uptime();
}



// Memory
window.freemem = function(){
    return _os.freemem() / ( 1024 * 1024 );
}

window.totalmem = function(){

    return _os.totalmem() / ( 1024 * 1024 );
}

window.freememPercentage = function(){
    return _os.freemem() / _os.totalmem();
}

window.freeCommand = function(callback){

    // Only Linux
    require('child_process').exec('free -m', function(error, stdout, stderr) {

       var lines = stdout.split("\n");


       var str_mem_info = lines[1].replace( /[\s\n\r]+/g,' ');

       var mem_info = str_mem_info.split(' ')

       total_mem    = parseFloat(mem_info[1])
       free_mem     = parseFloat(mem_info[3])
       buffers_mem  = parseFloat(mem_info[5])
       cached_mem   = parseFloat(mem_info[6])

       used_mem = total_mem - (free_mem + buffers_mem + cached_mem)

       callback(used_mem -2);
    });
}


// Hard Disk Drive
window.harddrive = function(callback){

    require('child_process').exec('df -k', function(error, stdout, stderr) {

        var total = 0;
        var used = 0;
        var free = 0;

        var lines = stdout.split("\n");

        var str_disk_info = lines[1].replace( /[\s\n\r]+/g,' ');

        var disk_info = str_disk_info.split(' ');

        total = Math.ceil((disk_info[1] * 1024)/ Math.pow(1024,2));
        used = Math.ceil(disk_info[2] * 1024 / Math.pow(1024,2)) ;
        free = Math.ceil(disk_info[3] * 1024 / Math.pow(1024,2)) ;

        callback(total, free, used);
    });
}



// Return process running current
window.getProcesses = function(nProcess, callback){

    // if nprocess is undefined then is function
    if(typeof nProcess === 'function'){

        callback =nProcess;
        nProcess = 0
    }

    command = 'ps -eo pcpu,pmem,time,args | sort -k 1 -r | head -n'+10
    //command = 'ps aux | head -n '+ 11
    //command = 'ps aux | head -n '+ (nProcess + 1)
    if (nProcess > 0)
        command = 'ps -eo pcpu,pmem,time,args | sort -k 1 -r | head -n'+(nProcess + 1)

    require('child_process').exec(command, function(error, stdout, stderr) {

        var that = this

        var lines = stdout.split("\n");
        lines.shift()
        lines.pop()

        var result = ''


        lines.forEach(function(_item,_i){

            var _str = _item.replace( /[\s\n\r]+/g,' ');

            _str = _str.split(' ')

            // result += _str[10]+" "+_str[9]+" "+_str[2]+" "+_str[3]+"\n";  // process
            result += _str[1]+" "+_str[2]+" "+_str[3]+" "+_str[4].substring((_str[4].length - 25))+"\n";  // process

        });

        callback(result);
    });
}



/*
* Returns All the load average usage for 1, 5 or 15 minutes.
*/
window.allLoadavg = function(){

    var loads = _os.loadavg();

    return loads[0].toFixed(4)+','+loads[1].toFixed(4)+','+loads[2].toFixed(4);
}

/*
* Returns the load average usage for 1, 5 or 15 minutes.
*/
window.loadavg = function(_time){

    if(_time === undefined || (_time !== 5 && _time !== 15) ) _time = 1;

    var loads = _os.loadavg();
    var v = 0;
    if(_time == 1) v = loads[0];
    if(_time == 5) v = loads[1];
    if(_time == 15) v = loads[2];

    return v;
}


window.cpuFree = function(callback){
    getCPUUsage(callback, true);
}

window.cpuUsage = function(callback){
    getCPUUsage(callback, false);
}

function getCPUUsage(callback, free){

    var stats1 = getCPUInfo();
    var startIdle = stats1.idle;
    var startTotal = stats1.total;

    setTimeout(function() {
        var stats2 = getCPUInfo();
        var endIdle = stats2.idle;
        var endTotal = stats2.total;

        var idle 	= endIdle - startIdle;
        var total 	= endTotal - startTotal;
        var perc	= idle / total;

        if(free === true)
            callback( perc );
        else
            callback( (1 - perc) );

    }, 1000 );
}

function getCPUInfo(callback){
    var cpus = _os.cpus();

    var user = 0;
    var nice = 0;
    var sys = 0;
    var idle = 0;
    var irq = 0;
    var total = 0;

    for(var cpu in cpus){
        if (!cpus.hasOwnProperty(cpu)) continue;
        user += cpus[cpu].times.user;
        nice += cpus[cpu].times.nice;
        sys += cpus[cpu].times.sys;
        irq += cpus[cpu].times.irq;
        idle += cpus[cpu].times.idle;
    }

    var total = user + nice + sys + idle + irq;

    return {
        'idle': idle,
        'total': total
    };
}