Build MVC Applications with Connectivity to Harvest Data



This article shows how to use only the Entity Framework and the CData ADO.NET provider to access Harvest from an ASP.NET MVC application.

In this article, we will guide you through the process of utilizing wizards within Visual Studio to seamlessly integrate the CData ADO.NET Provider for Harvest into a basic MVC (Model, View, Controller) project.

Create the Entity Framework Model

Follow the steps below to save connection properties and map tables to entities in the data model.

  1. Create a new MVC project in Visual Studio. In this example, the project name is MvcAPIApp.
  2. If you are using Entity Framework 6, you will need to take the preliminary step of registering the Harvest Entity Framework provider for your project. See the "LINQ and Entity Framework" chapter in the help documentation for a guide.

    Note that MVC 3 scaffolding and MVC 4 scaffolding do not support Entity Framework 6. You can use your scaffolding with Entity Framework 6 by upgrading to the latest version of MVC.

  3. To add the .edmx file from the designer, right-click your Models folder and click Add New Item. Select ADO.NET Entity Data Model, name the model, and click Add. In this example, the name of the model is APIModel.
  4. In the Entity Data Model wizard, select the option 'EF Designer from database'. The Entity Data Model wizard is displayed.
  5. Click New Connection. Select CData Harvest Data Source in the dialog that is displayed.
  6. Specify the required connection string properties.

    Start by setting the Profile connection property to the location of the Harvest Profile on disk (e.g. C:\profiles\Harvest.apip). Next, set the ProfileSettings connection property to the connection string for Harvest (see below).

    Harvest API Profile Settings

    To authenticate to Harvest, you can use either Token authentication or the OAuth standard. Use Basic authentication to connect to your own data. Use OAuth to allow other users to connect to their data.

    Using Token Authentication

    To use Token Authentication, set the APIKey to your Harvest Personal Access Token in the ProfileSettings connection property. In addition to APIKey, set your AccountId in ProfileSettings to connect.

    Using OAuth Authentication

    First, register an OAuth2 application with Harvest. The application can be created from the "Developers" section of Harvest ID.

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

    • ProfileSettings: Set your AccountId in ProfileSettings.
    • AuthScheme: Set this to OAuth.
    • OAuthClientId: Set this to the client ID that you specified in your app settings.
    • OAuthClientSecret: Set this to the client secret that you specified in your app settings.
    • CallbackURL: Set this to the Redirect URI that you specified in your app settings.
    • InitiateOAuth: Set this to GETANDREFRESH. You can use InitiateOAuth to manage how the driver obtains and refreshes the OAuthAccessToken.

    A typical connection string is below:

    Profile=C:\profiles\Harvest.apip;ProfileSettings='APIKey=my_personal_key;AccountId=_your_account_id';
  7. Name the connection and select whether to include sensitive information, such as connection credentials, in the connection string. For simplicity, this example saves sensitive information in Web.config. The connection settings are saved as APIEntities.

  8. Select the views you need. In this example, Invoices is imported. Also, the option to pluralize object names is deselected in this example. Click Finish to create the .edmx file.
  9. Build your project to complete this step.

Scaffold the Controller and Views

Once you've established the model and completed the project build, you can employ ASP.NET Scaffolding wizards to generate both the controller and the views.

  1. In Solution Explorer, right-click the controllers folder and click Add -> Controller. Select MVC 5 Controller with views, using Entity Framework.
  2. In the Add Controller dialog that is then displayed, select the following options:

    • Model class: Select a table you imported; for example, Invoices.
    • Data context class: Select your context class.
  3. Leave the default values for the other fields.

You can now access the list of Invoices records at http://MySite/Invoices. With every state change the site picks up any data changes.

Ready to get started?

Connect to live data from Harvest with the API Driver

Connect to Harvest