Consume Foursquare OData Feeds in PowerBuilder

The CData API Server produces secure feeds of Foursquare data that you can consume in PowerBuilder DataWindows. The API Server supports the major Web services, including OData, Atom, JSON, HTML, CSV, TSV, and RSS. It also supports the major authentication schemes and SSL.

This article shows how to create a DataWindow that uses the CData API Server to retrieve data.

Set Up the API Server

Follow the steps below to begin producing secure Foursquare OData services:

Deploy

The API Server runs on your own server. On Windows, you can deploy using the stand-alone server or IIS. On a Java servlet container, drop in the API Server WAR file. See the help documentation for more information and how-tos.

The API Server is also easy to deploy on Microsoft Azure, Amazon EC2, and Heroku.

Connect to Foursquare

After you deploy the API Server, provide authentication values and other connection properties needed to connect to Foursquare by clicking Settings -> Connections and adding a new connection in the API Server administration console.

Using API Key Authentication

Foursquare Places API uses Service Key (Bearer token) authentication. To obtain a Service Key:

1. Go to the Foursquare Developer Console at https://foursquare.com/developers/
2. Create a new project or select an existing one
3. Navigate to the API Keys section
4. Generate a new Service Key for the Places API

After setting the following connection properties, you are ready to connect:

• AuthScheme: Set this to APIKey.
• ServiceKey: Set this to your Foursquare Service Key obtained from the Developer Console.
• XPlacesApiVersion: (Optional) Set this to the API version date. Defaults to 2025-06-17.

Example APIKey connection string

Profile=C:\profiles\Foursquare.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_personal_access_token';

You can then choose the Foursquare entities you want to allow the API Server access to by clicking Settings -> Resources.

Additionally, click Settings -> Server and change the following settings for compatibility with PowerBuilder:

• Default Format: Select XML (Atom) in the menu.
• Default Version: Select 2.0 in the menu.

Authorize API Server Users

After determining the OData services you want to produce, authorize users by clicking Settings -> Users. The API Server uses authtoken-based authentication and supports the major authentication schemes. Access can also be restricted based on IP address; by default, only connections to the local machine are allowed. You can authenticate as well as encrypt connections with SSL.

Create a Profile for Foursquare

Follow the steps below to use the Database Painter tool to create a database profile for the OData API of the API Server. In the Database Painter, you can graphically manipulate data as well as execute SQL queries.

1. Click Tools -> Database Painter.
2. Right-click the OData node and click New Profile.
3. In the Database Profile Setup dialog, enter the following:
   • Profile Name: Enter a user-friendly name for the profile.
   • URI: Enter the URL to the OData endpoint of the API Server. This URL will resemble the one below:

     http://MyServer:8080/api.rsc

   • Supply User Id and Password: Click this option to use HTTP Basic authentication. Note that the API Server also supports Windows authentication.
   • User Id: Enter the name of an user in the API Server.
   • Password: Enter the authtoken of an user in the API Server.
   
4. To view and modify a table, right-click a table and then click Edit Data -> Grid.

Using Foursquare Data with PowerBuilder Controls

You can use standard PowerBuilder objects to connect to OData feeds and execute queries. The following example shows how to retrieve Foursquare data into a DataWindow.

You can add the following code to the open method:

SQLCA.DBMS = "ODT"
SQLCA.DBParm = "ConnectString='URI=http://MyServer:8080/api.rsc;UID=MyAPIUser;PWD=MyAuthtoken'";
CONNECT USING SQLCA;
dw_autocomplete.SetTransObject(SQLCA);
dw_autocomplete.Retrieve();