Function returns an empty array

Question

i can't find the bug in this function. It returns every time an empty array. Hope someone can help me.

https://gist.github.com/podkopaev/8406346

portal.getHosterByStream = function(stream, callback) {
    request(URL + stream, function (error, response, body) {
        if (!error && response.statusCode === 200) {
            var hoster = [];
            var $ = cheerio.load(body);
            var information = $('body div[id=frmMain] div[id=dontbeevil] div[id=Vadda]').html();
            var items_hoster = $(information).find("ul[id=HosterList]").html();

            $(items_hoster).each(function (i, item) {
                var rel = $(item).attr('rel');

                if (rel != undefined) {
                    request(MIRROR + rel, function (error, response, body) {
                        if (!error && response.statusCode === 200) {
                            var host = JSON.parse(body);

                            var href = "";
                            var positionHref = 9;
                            var i = 0;

                            while (host.Stream.substr(positionHref + i, 1) != '"') {
                                href = util.format('%s%s', href, host.Stream.substr(positionHref + i, 1));

                                i++;
                            }
                            hoster.push(href);
                        } else {
                            console.log('error second request');
                        }
                    });
                }
            });
            callback(hoster);
        } else {
            console.log('error request page');
        }
    });
}

JohnnyHK · Accepted Answer · 2014-01-26 14:27:42Z

2

request() is async, so you're calling callback(hoster) before any of your hoster.push(href) calls get a chance to execute.

So change your code to not call callback(hoster) until all of your request() callbacks have completed.

UPDATE

In your latest gist, you're calling callback(null, 103); before your request calls have called their callbacks and populated hoster.

Instead of rel.forEach, use async.eachSeries in a pattern like:

async.eachSeries(rel, function(item, cb) {
        request(MIRROR + item, function (error, response, body) {
            if (!error && response.statusCode === 200) {
                ...
                hoster.push(href);
            }
            cb();
        });
    }, function(err) {
        // This won't get called until all the request callbacks are done.
        callback(null, 103);
    }
);

edited Jan 26, 2014 at 14:27

answered Jan 16, 2014 at 19:39

JohnnyHK

313k70 gold badges632 silver badges479 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

deno Over a year ago

could you please help me with the code. i am new to node.js and trying to fix this bug for a week now.

JohnnyHK Over a year ago

@user3197431 Has my answer helped you understand the problem with your code?

deno Over a year ago

Yeah it helped me understanding the problem. I tried to find a workaround with the async library but it didn't work to me.

JohnnyHK Over a year ago

@user3197431 Edit your question to show how you tried to solve this with async and hopefully we can tell you what you're doing wrong.

deno Over a year ago

Me again. It doesn't work. This is my current code. gist.github.com/podkopaev/8632141 The variable hoster is still empty.

Collectives™ on Stack Overflow

Function returns an empty array

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related