LINQ to Perigon Data

This article illustrates using LINQ to access tables within the Perigon via the CData ADO.NET Data Provider for Perigon. To achieve this, we will use LINQ to Entity Framework, which facilitates the generation of connections and can be seamlessly employed with any CData ADO.NET Data Providers to access data through LINQ.

See the help documentation for a guide to setting up an EF 6 project to use the provider.

1. In a new project in Visual Studio, right-click on the project and choose to add a new item. Add an ADO.NET Entity Data Model.
2. Choose EF Designer from Database and click Next.
3. Add a new Data Connection, and change your data source type to "CData Perigon Data Source".

4. Enter your data source connection information.

   Using API Key Authentication

   To use the Perigon API, you need to obtain an API key from your Perigon account. Navigate to the Perigon dashboard and generate an API key from your account settings.

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

   • AuthScheme: Set this to APIKey.
   • APIKey: Set this to your Perigon API key.

   Example connection string:

   Profile=C:\profiles\Perigon.apip;AuthScheme=APIKey;ProfileSettings="APIKey=your_api_key"
   

   Available Tables

   The Perigon profile provides access to the following tables:

   • Articles - News articles retrieved from the Perigon news intelligence API
   • Headlines - Story clusters grouping related headline articles
   • Sources - News sources tracked by the Perigon news intelligence API
   • Journalists - Journalist profiles tracked by the Perigon news intelligence API

   Below is a typical connection string:

   Profile=C:\profiles\Perigon.apip;AuthScheme=APIKey;ProfileSettings="APIKey=your_api_key"


5. If saving your entity connection to App.Config, set an entity name. In this example we are setting APIEntities as our entity connection in App.Config.
6. Enter a model name and select any tables or views you would like to include in the model.

Using the entity you created, you can now perform select commands. For example:

APIEntities context = new APIEntities();

var articlesQuery = from articles in context.Articles
  select articles;

foreach (var result in articlesQuery) {
  Console.WriteLine("{0} {1} ", result.Id, result.);
}

See "LINQ and Entity Framework" chapter in the help documentation for example queries of the supported LINQ.