Provide OData Services of HCL Domino Data from a WCF Application



In this article, we will demonstrate the process of generating an OData feed for HCL Domino data by developing a WCF Service Application.

The CData ADO.NET Provider for HCL Domino enables you to rapidly develop service-oriented applications using the Windows Communication Foundation (WCF) framework, providing HCL Domino data data to OData consumers. This article guides you through creating an entity data model for connectivity and a WCF Data Service to expose OData services. You can then consume the feed with various OData clients, such as Power Pivot or applications using the CData ADO.NET Provider for OData.

Create the OData Service

Follow the steps below to create a WCF service application that will provide connectivity to HCL Domino data via OData.

  1. Open Visual Studio and create a new project. Select the WCF Service Application template.
  2. Delete the autogenerated IService.cs and Service1.svc.
  3. Install Entity Framework 6:

    Use the Package Manager Console in Visual Studio to install the latest version of Entity Framework. Run the following command to download and install Entity Framework automatically: Install-Package EntityFramework

  4. Register the Entity Framework provider:
    1. Add the following provider entry in the "providers" section of your App.config or Web.config file. This section should already exist if the Entity Framework installation was successful. <configuration> ... <entityFramework> <providers> ... <provider invariantName="System.Data.CData.Domino" type="System.Data.CData.Domino.DominoProviderServices, System.Data.CData.Domino.Entities.EF6" /> </providers> </entityFramework> </configuration>
    2. Add a reference to System.Data.CData.Domino.Entities.dll, located in lib/4.0 in the installation directory.
    3. Build the project to complete the setup for using EF6.
  5. Click Project -> Add New Item -> ADO.NET Entity Data Model.
  6. In the Entity Data Model wizard that is displayed, select the 'EF Designer from Database' option.
  7. In the resulting Choose Your Connection dialog, click New Connection.
  8. In the Connection properties dialog, select the CData HCL Domino Data Source and enter the necessary credentials.

    A typical connection string is below:

    Server=https://domino.corp.com;AuthScheme=OAuthPassword;User=my_domino_user;Password=my_domino_password;

    Connecting to Domino

    To connect to Domino data, set the following properties:

    • URL: The host name or IP of the server hosting the Domino database. Include the port of the server hosting the Domino database. For example: http://sampleserver:1234/
    • DatabaseScope: The name of a scope in the Domino Web UI. The driver exposes forms and views for the schema governed by the specified scope. In the Domino Admin UI, select the Scopes menu in the sidebar. Set this property to the name of an existing scope.

    Authenticating with Domino

    Domino supports authenticating via login credentials or an Azure Active Directory OAuth application:

    Login Credentials

    To authenticate with login credentials, set the following properties:

    • AuthScheme: Set this to "OAuthPassword"
    • User: The username of the authenticating Domino user
    • Password: The password associated with the authenticating Domino user

    The driver uses the login credentials to automatically perform an OAuth token exchange.

    AzureAD

    This authentication method uses Azure Active Directory as an IdP to obtain a JWT token. You need to create a custom OAuth application in Azure Active Directory and configure it as an IdP. To do so, follow the instructions in the Help documentation. Then set the following properties:

    • AuthScheme: Set this to "AzureAD"
    • InitiateOAuth: Set this to GETANDREFRESH. You can use InitiateOAuth to avoid repeating the OAuth exchange and manually setting the OAuthAccessToken.
    • OAuthClientId: The Client ID obtained when setting up the custom OAuth application.
    • OAuthClientSecret: The Client secret obtained when setting up the custom OAuth application.
    • CallbackURL: The redirect URI defined when you registered your app. For example: https://localhost:33333
    • AzureTenant: The Microsoft Online tenant being used to access data. Supply either a value in the form companyname.microsoft.com or the tenant ID.

      The tenant ID is the same as the directory ID shown in the Azure Portal's Azure Active Directory > Properties page.

  9. Select HCL Domino tables and views that you want OData clients to access.
  10. Click Project -> Add New Item -> WCF Data Service.
  11. Specify the data source class and configure access to the new WCF Data Service. In the example below, the Access Rule for the entities is set to All. This means that any user will be able to read and modify data.

    using System; using System.Collections.Generic; using System.Data.Services; using System.Data.Services.Common; using System.Linq; using System.ServiceModel.Web; using System.Web; namespace DominoService{ public class DominoDataService : DataService<DominoEntities> { public static void InitializeService(DataServiceConfiguration config) { config.SetEntitySetAccessRule("*", EntitySetRights.All); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V3; } } }
  12. Run the project. Applications that support OData can now access the Salesforce data and reflect any changes. You can access the feed in your browser. The feed will resemble the following:

Consume the OData Service from Power Pivot

You can now use the service from any OData client; for example, Excel Power Pivot.

  1. Open Excel and click on the Power Pivot Window button.
  2. A new pop-up will appear. Select the option From Data Feeds.
  3. In the resulting Table Import Wizard, enter the OData URL. For example, http://localhost:12449/DominoDataService.svc/.
  4. After connecting to the OData service, click the Next button at the bottom of the window.
  5. A table listing of the available tables will appear in the next window of the wizard. Select which tables you want to import and click Finish.
  6. Click Close to import the data in Power Pivot.

Ready to get started?

Download a free trial of the HCL Domino Data Provider to get started:

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