How to Access Talkdesk Data Using Entity Framework

Microsoft Entity Framework serves as an object-relational mapping framework for working with data represented as objects. Although Visual Studio offers the ADO.NET Entity Data Model wizard to automatically generate the Entity Model, this model-first approach may present challenges when your data source undergoes changes or when you require greater control over entity operations. In this article, we will delve into the code-first approach for accessing Talkdesk data through the CData ADO.NET Provider, providing you with more flexibility and control.

1. Open Visual Studio and create a new Windows Form Application. This article uses a C# project with .NET 4.5.
2. Run the command 'Install-Package EntityFramework' in the Package Manger Console in Visual Studio to install the latest release of Entity Framework.

3. Modify the App.config file in the project to add a reference to the Talkdesk Entity Framework 6 assembly and the connection string.

   Talkdesk uses the OAuth 2.0 Client Credentials grant. There is no browser-based authorization step and no callback URL.

   Set the following connection properties:

   • AccountName: The name of your Talkdesk account.
   • Region: The region where your Talkdesk instance is deployed. Supported values are US (default), EU, CA, AU, UK, and FedRamp.
   • OAuthClientId: The Client Id assigned when you registered your custom OAuth application.
   • OAuthClientSecret: The Client Secret assigned to your custom OAuth application.

   Creating a Custom OAuth Application

   1. Log in to your Talkdesk account and select OAuth Clients from the navigation menu.
   2. Click Create OAuth Client and give the client a descriptive name.
   3. Set Grant Type to Client Credentials.
   4. Click Add scopes and select the scopes for the data you want to access.
   5. Click Create and copy the Client Id and Client Secret.

   When you connect, the driver automatically requests an access token from Talkdesk, caches it, and refreshes it when it expires. Make sure the scopes selected for the application match the views you plan to query, or the token request can fail.

   
   
   <configuration>
      ... 
     <connectionStrings>
       <add name="TalkdeskContext" connectionString="Offline=False;AccountName=myAccount;Region=US;OAuthClientId=myClientId;OAuthClientSecret=myClientSecret;" providerName="System.Data.CData.Talkdesk" />
     </connectionStrings>
     <entityFramework>
       <providers>
          ... 
         <provider invariantName="System.Data.CData.Talkdesk" type="System.Data.CData.Talkdesk.TalkdeskProviderServices, System.Data.CData.Talkdesk.Entities.EF6" />
       </providers>
     <entityFramework>
   </configuration>
   </code> 
   

4. Add a reference to System.Data.CData.Talkdesk.Entities.EF6.dll, located in the lib -> 4.0 subfolder in the installation directory.
5. Build the project at this point to ensure everything is working correctly. Once that's done, you can start coding using Entity Framework.
6. Add a new .cs file to the project and add a class to it. This will be your database context, and it will extend the DbContext class. In the example, this class is named TalkdeskContext. The following code example overrides the OnModelCreating method to make the following changes:
   • Remove PluralizingTableNameConvention from the ModelBuilder Conventions.
   • Remove requests to the MigrationHistory table.

   
   
   using System.Data.Entity;
   using System.Data.Entity.Infrastructure;
   using System.Data.Entity.ModelConfiguration.Conventions;
   
   class TalkdeskContext : DbContext {
     public TalkdeskContext() { }
   
     protected override void OnModelCreating(DbModelBuilder modelBuilder)
     {
       // To remove the requests to the Migration History table
       Database.SetInitializer<TalkdeskContext>(null);  
       // To remove the plural names    
       modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
     }  
   }
   

7. Create another .cs file and name it after the Talkdesk entity you are retrieving, for example, Users. In this file, define both the Entity and the Entity Configuration, which will resemble the example below:

   
   
   using System.Data.Entity.ModelConfiguration;
   using System.ComponentModel.DataAnnotations.Schema;
   
   [System.ComponentModel.DataAnnotations.Schema.Table("Users")]
   public class Users {
     [System.ComponentModel.DataAnnotations.Key] 
     public System.String Id { get; set; }
     public System.String Name { get; set; }
   }
       
   

8. Now that you have created an entity, add the entity to your context class:

   
   
   public DbSet<Users> Users { set; get; }
   

9. With the context and entity finished, you are now ready to query the data in a separate class. For example:

   
   TalkdeskContext context = new TalkdeskContext();
   context.Configuration.UseDatabaseNullSemantics = true;
   var query = from line in context.Users select line;