How to Access Sage 300 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 Sage 300 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 Sage 300 Entity Framework 6 assembly and the connection string.

   Sage 300 requires some initial setup in order to communicate over the Sage 300 Web API.

   • Set up the security groups for the Sage 300 user. Give the Sage 300 user access to the option under Security Groups (per each module required).
   • Edit both web.config files in the /Online/Web and /Online/WebApi folders; change the key AllowWebApiAccessForAdmin to true. Restart the webAPI app-pool for the settings to take.
   • Once the user access is configured, click https://server/Sage300WebApi/ to ensure access to the web API.

   Authenticate to Sage 300 using Basic authentication.

   Connect Using Basic Authentication

   You must provide values for the following properties to successfully authenticate to Sage 300. Note that the provider reuses the session opened by Sage 300 using cookies. This means that your credentials are used only on the first request to open the session. After that, cookies returned from Sage 300 are used for authentication.

   • Url: Set this to the url of the server hosting Sage 300. Construct a URL for the Sage 300 Web API as follows: {protocol}://{host-application-path}/v{version}/{tenant}/ For example, http://localhost/Sage300WebApi/v1.0/-/.
   • User: Set this to the username of your account.
   • Password: Set this to the password of your account.

   <configuration>
    ... 
    <connectionStrings>
    <add name="Sage300Context" connectionString="Offline=False;User=SAMPLE;Password=password;URL=http://127.0.0.1/Sage300WebApi/v1/-/;Company=SAMINC;" providerName="System.Data.CData.Sage300" />
    </connectionStrings>
    <entityFramework>
    <providers>
    ... 
    <provider invariantName="System.Data.CData.Sage300" type="System.Data.CData.Sage300.Sage300ProviderServices, System.Data.CData.Sage300.Entities.EF6" />
    </providers>
    <entityFramework>
   </configuration>
   </code> 
   

4. Add a reference to System.Data.CData.Sage300.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 Sage300Context. 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 Sage300Context : DbContext {
    public Sage300Context() { }
   
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
    // To remove the requests to the Migration History table
    Database.SetInitializer<Sage300Context>(null); 
    // To remove the plural names 
    modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
    } 
   }
   

7. Create another .cs file and name it after the Sage 300 entity you are retrieving, for example, OEInvoices. 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("OEInvoices")]
   public class OEInvoices {
    [System.ComponentModel.DataAnnotations.Key] 
    public System.String InvoiceUniquifier { get; set; }
    public System.String ApprovedLimit { get; set; }
   }
    
   

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

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

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

   Sage300Context context = new Sage300Context();
   context.Configuration.UseDatabaseNullSemantics = true;
   var query = from line in context.OEInvoices select line;