CALL BACKS NODE JS ORDENADAMENTE

EJEMPLO DE ORDENAMIENTO DE CALL BACKS EN NODE JS CON LA LIBRERIA ASYNC

var async = require('async');

async.waterfall([

function (cb){
artist.findEvents('Miley', cb);
},
function (concert, cb){
concert.findTickets({price: {$lt: 100}}, cb);
},
function (tickets, cb){
tickets.purchase({cc: 424242424242}, cb);
},
function (transaction, cb) {
email.confirm(customer, transaction, cb);
}
],

//FUNCTION RETORNO
function (null, status){
if(err){
res.send(err);
return false;
}

res.send({
tickets: 'purchased'
});
}
);//FIN WATERFALL

//PATRON PROMISES DE COMMONJS - promises-aplus.github.io/promises-spec/
artist.find('Miley')
.findEvents({city: 'Bogota'})
.findTickets({price: {$lt: 100}}, cb);
.purchase({cc: 424242424242}, cb);

.then (function(transaction) {
customer.transaction = transaction;
return customer.save();
})

.then (function (customer, transaction) {
return email.confirm(customer, transaction);
})

.then function(){
res.send({
tickets: 'purchased'
});
},

function (err) {
console.log('Ha habido un error', err);
}
);

EJEMPLO DE CALL BACKS DESORDENADOS

function startExecution() {
doSomethingAsync(function(error, result) {
doSomethingElseAsync(function(error, result) {
moreAsync(function(error, result) {
evenMoreAsync(function(error, result) {
// ... I think you got it
});
});
});
});
};