How to Setup Twitter Integration

Registered users can also download Linq2Twitter sample. Please register an account to get a copy.

In this article:

• AuthenticationAccount Information
• Friends and Followers
• Get Statuses and Retweets
• Update Status
• How to Retweet
• References

Introduction

Twitter is a micro-blogging service that allows people to post messages. The maximum length of each message is 140 characters. Twitter enables social networking by allowing people to follow and communicate with each other. Over time, this has proven to be a powerful communications medium because of its real-time nature.

Whenever news breaks around the world, people are tweeting that news as it happens. This article will talk about how to integrate twitter API into ASP.NET application. There are few libraries introduced in twitter developer website for using in .NET application

All may have its own pros & cons. This article will focused on LinqToTwitter library which as its name shown completely based on linQ. You can download the source code or dll’s from codeplex. Then you should add references to your web applications.

How to Start

First thing you should consider for creating any twitter application is you have to register the application and get Consumer key and Consumer secret:



These keys should be kept on safe place.  Web.config is good place to put these keys and it is easy to access them through all places in ASP.NET application.

Authentication

private WebAuthorizer auth;
    
    protected void Page_Load(object sender, EventArgs e)
    {
        IOAuthCredentials credentials = new SessionStateCredentials();
        
        if (credentials.ConsumerKey == null || credentials.ConsumerSecret == null)
        {
            credentials.ConsumerKey = ConfigurationManager.AppSettings["twitterConsumerKey"];
            credentials.ConsumerSecret = ConfigurationManager.AppSettings["twitterConsumerSecret"];
        }

        auth = new WebAuthorizer
        {
            Credentials = credentials,
            PerformRedirect = authUrl => Response.Redirect(authUrl)
        };
        
        if (!Page.IsPostBack)
        {
            auth.CompleteAuthorization(Request.Url);
        }

        if (string.IsNullOrWhiteSpace(credentials.ConsumerKey) ||
            string.IsNullOrWhiteSpace(credentials.ConsumerSecret))
        {
            // The user needs to set up the web.config file to include Twitter consumer key and secret.
            lblInfo.Text = "Please set up Consumekey and ConsumerSecret in your web.config";
        }
        else if (auth.IsAuthorized)
        {
            screenNameLabel.Text = "Logged in as " + auth.ScreenName;
            lblInfo.Text = "";            
        }
        else {
            
            lblInfo.Text = "You are not authorized from twitter.";
        }

    }

protected void authorizeTwitterButton_Click(object sender, EventArgs e)
    {
        auth.BeginAuthorization(Request.Url);
    }

The WebAuthorizer class is the class will do the OAuth authentication for you, when user click on authorize button the browser will be redirected to a page like this:



So the page will redirect to twitter site and user will pass his username/password to twitter website, not the application. After successful authentication the page will be redirect to application callback URL and IOAuthCredentials property of WebAuthorizer class is loaded now.

Now the user is authenticated and can use his/her twitter account through the application features. There are few points should be considered, the credential will hold OAuthToken and AccessToken from twitter, these values can be hold in a Session and set in SessionStateCredentials class so user doesn’t need to login again and again when navigating through different pages of application, they can also save in database and in this way user will login into the website just once.

Account Information

Account class hold information related to twitter account, this contains numbers of Friends ( following account ) , Followers, Updates and favorites. So to get these information a linQ query should be written from this class:

twitterCtx = new TwitterContext(auth);
var accountTotals =
                (from acct in twitterCtx.Account
                 where acct.Type == AccountType.Totals
                 select acct.Totals)
                .SingleOrDefault();

lblFriends.Text = accountTotals.Friends.ToString();
lblFollowers.Text = accountTotals.Followers.ToString();
lblupdates.Text = accountTotals.Updates.ToString();
lblFavourites.Text = accountTotals.Favorites.ToString();

From a coding experience perspective, the TwitterContext type is analogous to DataContext (LINQ to SQL) or ObjectContext (LINQ to Entities). TwitterContext instance, twitterCtx uses to access IQueryable<T> tweet categories.

Each tweet category has a Type property for the type of tweets wants to get back. For example, Status tweets can be made for Public, Friend, or User timelines. Each tweet category has a type enum to helps figure out what is available.

Just like other LINQ providers, IQueryable<T>returns from the query. You can see how to materialize the query by invoking the ToList operator. Just like other LINQ providers, LINQ to Twitter does deferred execution, so operators such as ToList and ToArray or statements such as for and foreach loops will cause the query to execute and make the actual call to Twitter.

Friends and Followers

twitterCtx = new TwitterContext(auth);

        var friends =
                from tweet in twitterCtx.User
                where tweet.Type == UserType.Friends &&
                      tweet.ID == auth.UserId
                select tweet;


        gvFriends.DataSource = friends;
        gvFriends.DataBind();

        var followers =
                from tweet in twitterCtx.User
                where tweet.Type == UserType.Followers &&
                      tweet.ID == auth.UserId
                select tweet;


        gvFollowers.DataSource = followers;
        gvFollowers.DataBind();

This class contains other information related to user like Categories, Lookup and Search. This can be used the same way as Friends and followers.

Get Statuses and Retweets

To get statuses from your friends Status class can be queries, it contains different type of filters which can be included in Where clause. As an example this block of code will return statuses by friends:

twitterCtx = new TwitterContext(auth);
var tweets =
            from tweet in twitterCtx.Status
            where tweet.Type == StatusType.Friends
            select tweet;        

StatusType is an enum which can be used to get retweets by me, or retweets by specific user and also retweets by/to me/user. Nice and easy.

Update Status

Updating status is very easy and one line of the code:

twitterCtx.UpdateStatus(“New status”);

There are many overloads for this method, for example it gets inReplyToStatusId , Latitude, Longitude, placeId…

How to Retweet

Again this part is very easy, only StatusID of tweet is needed:

twitterCtx = new TwitterContext(auth);

var retweet = twitterCtx.Retweet(txtStatusId.Text);

lblInfo.Text = "User: " + retweet.Retweet.RetweetingUser.Name +
                " - Tweet: " + retweet.Retweet.Text +
                " - Tweet ID: " + retweet.Retweet.ID 

Retweet method returns a Status object which holds information related to the tweet.

References

• Twitter Developer Website
• LinqToTwitter website

Registered users can also download Linq2Twitter sample. Please register an account to get a copy.