Create REST-Connected Enterprise Applications in OutSystems

OutSystems is a low-code platform which provides the tools for companies to developer, deploy, and manage omnichannel enterprise applications. When paired with CData Connect Cloud, you get instant, cloud-to-cloud access to REST data for business applications. This article shows how to create a virtual database for REST in Connect Cloud and build a simple app from REST data in OutSystems.

The CData Connect Cloud provides a pure cloud-to-cloud interface for REST, allowing you to build reports from live REST data in OutSystems — without replicating the data to a natively supported database. As you create applications to work with data, OutSystems generates SQL queries to gather data. Using optimized data processing out of the box, CData Connect Cloud pushes all supported SQL operations (filters, JOINs, etc.) directly to REST, leveraging server-side processing to quickly return the requested REST data.

Configure REST Connectivity for OutSystems

Connectivity to REST from OutSystems is made possible through CData Connect Cloud. To work with REST data from OutSystems, we start by creating and configuring a REST connection.

1. Log into Connect Cloud, click Connections and click Add Connection
2. Select "REST" from the Add Connection panel
3. Enter the necessary authentication properties to connect to REST.

   See the Getting Started chapter in the data provider documentation to authenticate to your data source: The data provider models REST APIs as bidirectional database tables and XML/JSON files as read-only views (local files, files stored on popular cloud services, and FTP servers). The major authentication schemes are supported, including HTTP Basic, Digest, NTLM, OAuth, and FTP. See the Getting Started chapter in the data provider documentation for authentication guides.

   After setting the URI and providing any authentication values, set Format to "XML" or "JSON" and set DataModel to more closely match the data representation to the structure of your data.

   The DataModel property is the controlling property over how your data is represented into tables and toggles the following basic configurations.

   • Document (default): Model a top-level, document view of your REST data. The data provider returns nested elements as aggregates of data.
   • FlattenedDocuments: Implicitly join nested documents and their parents into a single table.
   • Relational: Return individual, related tables from hierarchical data. The tables contain a primary key and a foreign key that links to the parent document.

   See the Modeling REST Data chapter for more information on configuring the relational representation. You will also find the sample data used in the following examples. The data includes entries for people, the cars they own, and various maintenance services performed on those cars.

   
4. Click Create & Test
5. Navigate to the Permissions tab in the Add REST Connection page and update the User-based permissions.

Add a Personal Access Token

If you are connecting from a service, application, platform, or framework that does not support OAuth authentication, you can create a Personal Access Token (PAT) to use for authentication. Best practices would dictate that you create a separate PAT for each service, to maintain granularity of access.

1. Click on your username at the top right of the Connect Cloud app and click User Profile.
2. On the User Profile page, scroll down to the Personal Access Tokens section and click Create PAT.
3. Give your PAT a name and click Create.
4. The personal access token is only visible at creation, so be sure to copy it and store it securely for future use.

With the connection configured, you are ready to connect to REST data from OutSystems.

Connect to REST from OutSystems

The steps below outline connecting to CData Connect Cloud from OutSystems to create a new REST database connection.

1. Open OutSystems Service Studio
2. Click the gear icon to open Environment Management in the Service Center
3. Click Administration and select "Database Connections"
4. Click "New Database Connection"
5. Configure the database connection:
   • Name: name the connection (e.g. CData Connect Cloud REST)
   • DBMS: SQL Server / Azure SQL
   • Username: a Connect Cloud user (e.g. [email protected])
   • Password: the PAT for the Connect Cloud user
   • Server: tds.cdata.com,14333
   • Schema: the name of your REST connection (e.g. REST1)
   
6. Click "Test Connection"
7. Click "Create"

Map REST Tables or Views to Entities in an Extension Module

Once you create the database connection for REST, you can create an extension that maps the tables or views to OutSystems entities. If you have not already done so, create an Application in Service Studio.

1. Open the Service Studio and open the existing Application
2. Click "Add Module," set the "Module Name" (e.g. rest_db_extension), set "Module Type" to "Extension," and click "Create Module"
3. In Integration Studio, connect to your environment
4. Right-click "Entities" in the extension tree and select "Connect to External Table or View..."
5. Follow the steps in the wizard, selecting the tables and views you wish to work with
6. In the Integration Studio, click "1-Click Publish"
7. In the "1-Click Publish" wizard, click "Configure" when the process completes
   • In the Service Center, associate the logical database name of the extension to the database connection that the extension will use and click "Apply"
8. In your application, click "Manage Dependencies..."
9. Add a dependency to the Extension and select the Entities that you will use in your application

At this point, you can access and work with REST data just like you would with the standard OutSystems entities.

More Information & Free Trial

With Connect Cloud and OutSystems, you can easily build REST-connected applications. Request a free trial of Connect Cloud and start working with REST data in OutSystems today.