Ignoring AJAX errors with promises array and $.when

Question

I have the following code that gets the JSON from an array of YouTube video ids. It works great when all the videos exists and the query is successful. It sends several getJ

Answer 1

Unfortunately, jQuery doesn't come with this functionality.

Gladly, you can implement it yourself pretty easily.

var url = 'http://gdata.youtube.com/feeds/api/videos/{{vid}}?v=2&alt=json';
function getVideo(vid){
    var u = url.replace('{{vid}}', vid);
    return $.getJSON( u ).then(function(res){
         return {video:vid,result:res.entry};
    });
}
var promises = ['ozj2-bnTL3s','EAZ4Tlt8MQ4',"doesn'texist"].map(getVideo);

some(promises).then(function(results){
    for(var i = 0; i < results.length; i++) {
        console.log(results[i]); // log
    }
});



// get a hook on when all of the promises resolve, some fulfill
// this is reusable, you can use this whenever you need to hook on some promises
// fulfilling but all resolving.
function some(promises){
    var d = $.Deferred(), results = [];
    var remaining = promises.length;
    for(var i = 0; i < promises.length; i++){
        promises[i].then(function(res){
            results.push(res); // on success, add to results
        }).always(function(res){
            remaining--; // always mark as finished
            if(!remaining) d.resolve(results);
        })
    }
    return d.promise(); // return a promise on the remaining values
}

Here's a working JSFiddle of the result.