Question

I am building an app using ASP.NET 4.0.

I have a table called entries. Entries can be liked via Facebook. I want to implement the ability to sort via likes so I am taking the approach of storing the number of likes for each entry and using that column to order. The problem is the overhead involved in getting the number of likes. I think the method I am using could be improved as right now because fetching data for only 13 entries is taking 4 seconds, which is way too long.

I am using the FB graph api and JSON.NET to parse the response. In the following code I have a List of type Entry, I am getting the like url for the entry using an app setting combined with the entries id.
This is what I am doing:

   foreach (Entry entry in entries)
        {
            int likes;
            try
            {
               // the url that is tied to the entry
               string url = "http://graph.facebook.com/?ids=" + Properties.Settings.Default.likeUrl + "?id=" + entry.EntryId;
               //open a WebClient and get the results of the url
                WebClient client = new WebClient();

            Stream data = client.OpenRead(url);
            StreamReader reader = new StreamReader(data);
            string s = reader.ReadToEnd();
            //parse out the response
            var json = JObject.Parse(s);
            //shares are how many likes the entry has
            likes = Convert.ToInt32(json.First.First.SelectToken("shares").ToString());

        }
        catch (Exception ex)
        {
            likes = 0;
        }

    }   

As I said this method is very expensive. If anyone could suggest a better way to do what I am attempting here I would really appreciate the help. Thanks much!

Answer 1

Doing a separate API call for each item in the loop is going to be slow due to the overhead of making network requests. Have you looked into batching the query for the likes for all 13 items into a single API call? I don’t know specifically if it will work for the query you are running, but I know that the facebook API supports methods of batching queries. You can run the batches such that the output of one goes into other queries in the same batch. You may have to switch to making FQL queries via the Graph API.

You might also consider moving the API calls onto the client, and implement them using the javascript API. This will offload the API work to the users’ browsers, which will let your application scale better. If you don’t do this you should at least consider Robert’s suggestion of making the calls asynchronously.