Working with NASA Data in LINQPad

The CData ADO.NET Provider for NASA enables you to use standard ADO.NET interfaces like LINQ and the Entity Framework to work with NASA data. This article will demonstrate the process of establishing a connection from LINQPad and executing LINQ queries.

Create the Data Model

After downloading and installing both the provider and LINQPad, create a new class library project within Visual Studio.

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

1. Right-click your project and click Add -> New Item -> ADO.NET Entity Data Model. In the resulting dialog, select Code First from database. Click New Connection and specify the connection string options in the resulting wizard.

   Using API Key Authentication

   Most NASA API endpoints (APOD, NeoWS, DONKI, TechTransfer) require a NASA API key. Register for a free key at https://api.nasa.gov. The default DEMO_KEY provides limited access (30 requests/hour, 50 requests/day); a registered key allows 1,000 requests/hour.

   The following endpoints do not require an API key and work without authentication: EONET (Earth Observatory Natural Event Tracker), EPIC (Earth Polychromatic Imaging Camera), NASA Image and Video Library, and TechPort.

   After obtaining your API key, set the following connection properties:

   • AuthScheme: Set this to APIKey.
   • APIKey: Set this to your NASA API key. Use DEMO_KEY for limited testing.

   Example Connection String

   Profile=C:\profiles\NASA.apip;AuthScheme=APIKey;APIKey=YOUR_NASA_API_KEY
   

   Connecting to NASA

   Once the authentication is configured, you can connect to NASA and query data from any of the available tables such as AstronomyPictureOfDay, NearEarthObjectFeed, EonetEvents, and NasaImageLibrary.

   Below is a typical connection string:

   Profile=C:\profiles\NASA.apip;AuthScheme=APIKey;APIKey=YOUR_NASA_API_KEY

   👁 The required connection properties in the Entity Data Model Configuration Wizard. (JSON is shown.)
   

2. Select the desired tables and views and click Finish to create the data model.

   👁 The last step of the Entity Data Model Configuration Wizard, where tables are imported into the entity model.
   
3. Build the project. The generated files can be used to create the NASA connection in LINQPad.

Connect to NASA Data in LINQPad

After you have obtained the required connection properties and created the data model assembly, follow the steps below to start using the data model in LINQPad.

1. Open LINQPad and click Add Connection.

2. Select the "Use a typed data context from your own assembly" option.

3. Select Entity Framework DbContext.

   👁 The Choose Data Context dialog.
   

4. Click Browse next to the Path to Custom Assembly box and browse to your project folder. Browse to the .dll or .exe under the bin folder.

5. Select the name of the DbContext.
6. If you saved your connection string in App.Config, specify the path to the App.config.

You can now query NASA data through LINQPad. For examples of the supported LINQ queries, see the "LINQ and Entity Framework" chapter in the help documentation.