Question

I’m writing a library to access data from a server, and return formatted data to the consumer of my functions.
Here is an example of what I’d like to have:

// my code
var model = function () {
    return $.ajax(myRequest).done(function (rawData) {
        return treatment(data);
    });
}

// client code
var useModel = function () {
    var modelPromise = model();
    modelPromise.done(function (formattedData) { // consume this result })
}

where formattedData is the result of my first done callback and not the rawData.

Do you have any ideas?

Thanks

R.

Answer 1

Regis,

jQuery’s documention for .then() says :

As of jQuery 1.8, the deferred.then() method returns a new promise
that can filter the status and values of a deferred through a
function, replacing the now-deprecated deferred.pipe() method.

The second example for .then() is similar to what you want (though not involving ajax).

As far as I can tell, the necessary changes to your code are very minimal :

// my code
var model = function () {
    return $.ajax(myRequest).then(function (rawData) {
        return treatment(rawData);
    });
}

// client code
var useModel = function () {
    var modelPromise = model();
    modelPromise.done(function (formattedData) { // consume this result })
}