jQuery Recursive AJAX Call Promise

Question

I\'m still trying to figure out how to use jQuery deferred object in recursive AJAX call. I have a code like this

function request(page, items){    

    //b         


        

Answer 1

You should not use the success parameter if you want to work with promises. Instead, you want to return a promise, and you want to use then to transform the results of a promise into something different, possibly even another promise.

function request(page) {    
    …
    // return the AJAX promise
    return $.ajax({
        url: '/echo/json/',
        method: 'POST',
        dataType: 'json',
        data: {
            delay: 1,
            json: JSON.stringify(ret)
        }
    });
}

function requestOddsFrom(page, items) {
    return request(page).then(function(data){
        if (data.currentPage > data.totalPage) {
            return items;
        } else {
            var filtered = data.items.filter(function(el){ return el%2 == 1; });
            return requestOddsFrom(data.currentPage + 1, items.concat(filtered));
        }
    });
}

function requestAll(){
    return requestOddsFrom(1, []);
}

requestAll().then(function(items) {
    console.dir(items);
});