Sequence of actions

//1

function scrape(data, cb){
  setTimeout(function(){
    console.log(data);
    if (cb) cb();
  }, 1000);
}
function compose(args, cb){
  var l = args.length;
  var i = 0;
  if (l===0) return;
  var next = function(){
    if (i++>=l)
      return cb();
    args[i-1](next);
  };
  next();
}

var requests = [
  scrape.bind(null, 'url1'),
  scrape.bind(null, 'url2'),
  scrape.bind(null, 'url3')
]

compose(requests, console.log.bind(console, 'over'));

//2

function firstAction(data){
  setTimeout(function(){
    console.log(data[0]);
    secondAction(data);
  }, 1000);
}

function secondAction(data){
  setTimeout(function(){
    console.log(data[1]);
    thirdAction(data);
  }, 1000);
}

function thirdAction(data){
  setTimeout(function(){
    console.log(data[2]);
  }, 1000);
}

firstAction("abc");