SOURCE

Date.prototype.format = function (format) {
    var o = {
        "M+": this.getMonth() + 1,   //month
        "d+": this.getDate(),         //day
        "h+": this.getHours(),       //hour
        "m+": this.getMinutes(),   //minute
        "s+": this.getSeconds(),   //second
        "q+": Math.floor((this.getMonth() + 3) / 3),     //quarter
        "S": this.getMilliseconds()   //millisecond
    }
    if (/(y+)/.test(format)) format = format.replace(RegExp.$1,
        (this.getFullYear() + "").substr(4 - RegExp.$1.length));
    for (var k in o) if (new RegExp("(" + k + ")").test(format))
        format = format.replace(RegExp.$1,
            RegExp.$1.length == 1 ? o[k] :
                ("00" + o[k]).substr(("" + o[k]).length));
    return format;
};
String.prototype.format = function () {
    var args = arguments;
    if (args.length == 0) { return this; }
    var reg = /{(\d+)?}/g;
    return this.replace(reg, function ($0, $1) { return args[parseInt($1)]; })
}

function rnd(min,max){
  return Math.floor(Math.random()*(max-min+1)+min);;
}

function create_limit(){
  var today = new Date();
  today.setHours(0);
  today.setMinutes(0);
  today.setSeconds(0);
  
  var start = Math.floor(today.getTime()/1000);
  today.setHours(24);
  today.setMinutes(00);
  today.setSeconds(00);
  var end = Math.floor(today.getTime()/1000);
  
  return {
    start : start,
    end : end
  }
}

var limit = create_limit();
var data = [];
for(var i=0;i<10;i++){
  var time = rnd(limit.start,limit.end);
  data.push({
    value : rnd(30,100);
    time : rnd(limit.start,limit.end)
  });
}

console.log(data);