Tersus: Tersus SDK for Facebook Applications

Tersus SDK for Facebook ApplicationsDate: Apr 23, 2017Tags:FacebookThis SDK is probaby outdated. An initial version of the SDK was developed in 2008, and it was fully revised in mid 2013 to support the significant changes made to the Facebook API since then. It hasn't been checked or updated since, though.
Tersus SDK for Facebook Applications lets you easily create, test and deploy your own Facebook applications.It includes:

A skeleton Facebook application (TersusFacebookTest), which displays the pictures and current online statuses of all your friends and lets you classify some of them as “real friends”.

A library of models providing several useful Facebook services such as “Login”, "Get Logged-in User" and "Get Friend List".

Generic models "Call Facebook Method" and "Call Facebook FQL Method", which enable easy usage of additional Facebook services (the above library models also use them).

See Also: Tersus Events.Skeleton Facebook ApplicationTersusFacebookTest is a skeleton of an application that can be used as a starting point for developing your own Facebook application (see Importing an existing application into the Tersus Studio).The model of the skeleton application consists of the following:

'Main View', which contains a 'Top Row' with the application's logo and slogan, and 'Tabbed Pane' that contains a sample pane 'Sample Tab' that demonstrates the retrieval of the list of your Facebook friends.

The '<Init>' in 'Main View' manages the authentication process with Facebook (see details below).

To create your own Facebook application, modify "TersusFacebookTest" to implement the required functionality. You will also need to register the application at Facebook. We recommend that you start with registering the application at Facebook, which will enable you to quickly test it from within Tersus Studio, and only then do the modeling changes.Registering Your Application at Facebook

Go to Facebook Developers (follow the Developers link at the bottom of the page, or go directly to http://developers.facebook.com/).

Select Apps at the top of the screen. Press + Create New App.

Fill App Name (e.g. "MyFacebookApp"). Press Continue.

In the Basic setting screen, in the section Select how your app integrates with Facebook:

Select Website with Facebook Login, and fill Site URL (provide the URL of your Tersus application on your local machine, e.g. http://localhost:8080/MyFacebookApp, which will enable you to test the application on your computer before deploying it to Facebook).
Select App on Facebook, and fill Canvas URL (the URL by which your application will be known once deployed to Facebook, e.g. http://apps.facebook.com/MyFacebookApp).

Note (at the top of the screen) that your application has been assigned an App Id (application identification key, also known as Client Id), and App Secret (an authentication token, also knows as Client Secret).

Press Save Changes.

Starting Your Application from within Tersus Studio

Import the project TersusFacebookTest.tersus into the Tersus Studio (see Importing an existing application into the Tersus Studio).

Rename the project to your application's name:

In the 'Repository Explorer' view, rename the project from ‘TersusFacebookTest’ to the name of your application (say 'MyFacebookApp').
Rename the top level system accordingly (e.g. open the 'TersusFacebookTest’ package and rename ‘TersusFacebookTest' to 'MyFacebookApp').

Set your application's logo and slogan:

In the top level system, zoom into 'Main View', then zoom into 'Top Row', and then into 'Init Logo'. Set the logo path to an image file with your application's logo.
Zoom back to 'Top Row'. Rename the label to the slogan you want to be displayed at the top of the screen.

Configure the application's authentication with Facebook:

In 'Main View', zoom into '<Init>' and then into ‘Login or Get Access Token’.
Replace the values of 'Client Id' and 'Client Secret' with the values of the App Id and App Secret assigned to your application by Facebook.
Note that the third parameter required for the accessing Facebook, ‘Redirect UR’, is provided by the ‘Get Self URL’ action. It should match the Site URL you specified for you Facebook app.

Save your models and start the application. It should be automatically open in your browser.

If you are not logged in yet to Facebook, a Facebook login dialog should open, and after you login, you will be redirected by Facebook to the Site URL you specified (e.g. http://localhost:8080/TersusFacebookTest).

Basic Facebook LibraryThe "TersusFacebookTest" project includes the package 'Facebook', which contains the following models:

Login or Get Access Token: Ensures the user is logged-in to Facebook and gets an access token for further interactions with Facebook.

Get Logged-in User: Gets the details of the logged-in user.

Get Friend List: Gets the details of all the friends of the logged-in user.

Get User Picture URL: Gets the URL of a user's picture.

Calling Other Facebook ServicesThe package 'Facebook' also contains two generic interfaces 'Call Facebook Method' and 'Call Facebook FQL Method' for calling Facebook services.To model the calling of a service:

For the basic Graph API of Facebook, use 'Call Facebook Method' and provide the service parameters through the ‘Parameters’ trigger. For example, ‘Get Friend List’ is calling 'Call Facebook Method' with the parameter “me/friends” (as explained in https://developers.facebook.com/docs/getting-started/graphapi/).

For FQL queries (see https://developers.facebook.com/docs/technical-guides/fql/), use 'Call Facebook FQL Method', and provide the query through the ‘Query’ trigger. For example, ‘Fill Statuses’ is executing a query that retrieves the online presence status of all the friends of the logged-in user.

Both 'Call Facebook Method' and 'Call Facebook FQL Method' return the content of a URL returned by the called Facebook service. Sometimes we only need the URL itself, so we don’t have to call a service (see for example the modeling of ‘Get User Picture URL’).