Build NASA-Connected Web Apps in Servoy
Servoy is a rapid application development and deployment platform. When paired with the CData API Driver for JDBC, users can build NASA-connected apps that work with live NASA data. This article describes how to connect to NASA from Servoy and build a simple web app to display and search NASA data.
With built-in optimized data processing, the CData JDBC Driver offers unmatched performance for interacting with live NASA data. When you issue complex SQL queries to NASA, the driver pushes supported SQL operations, like filters and aggregations, directly to NASA and utilizes the embedded SQL engine to process unsupported operations client-side (often SQL functions and JOIN operations). Its built-in dynamic metadata querying lets you work with NASA data using native data types.
Connect to NASA in Servoy Developer
To build NASA-connected apps, you need to first create a data provider in Servoy Developer using the CData API Driver for JDBC.
- Install the JDBC Driver.
- Copy the JDBC Driver JAR file. (cdata.jdbc.api.jar) to the /application_server/drivers/ directory in the installation directory for Servoy.
- Open Servoy Developer.
- In the Solution Explorer, right-click Database Server (under Resources) and choose "Connect to existing database" -> "empty."
- Name the server.
- Click to show the advanced server settings.
Set the URL, for example: jdbc:api:Profile=C:\profiles\NASA.apip;AuthScheme=APIKey;APIKey=YOUR_NASA_API_KEY
Built-In Connection String Designer
For assistance in constructing the JDBC URL, use the connection string designer built into the NASA JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.
java -jar cdata.jdbc.api.jar
Fill in the connection properties and copy the connection string to the clipboard.
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.
- Select the Driver class you just copied, for example, cdata.jdbc.api.APIDriver
Build a NASA-Connected Web App
Once you have configured the connection to NASA in the Servoy Developer resources, you are ready to build apps with access to live NASA data.
Create a New Solution
- In the Server Explorer, right-click "All solutions" and select "Create new solution."
- Name the solution.
- Select the checkbox to include the "search" module.
- Click "Finish."
Create a New Form
Right-click "Forms" and select "Create new form."
- Name the form.
- Select a Datasource.
- Set the type (e.g., Simple) and click "Finish."
Add a Data Grid to the Form
- Drag a Data Grid component (from Servoy NG-Grids) onto the form.
Drag a column component onto the Data Grid and set the "dataprovider" property for each column component to a column from the NASA "table" (e.g., from the AstronomyPictureOfDay table).
Continue adding columns as desired.
Add Searching to the App
Note that the "svySearch" extension is required to add search functionality (included by default when you create a new solution). If you did not add the extension when you created the solution or you are modifying an existing solution, you can add the search module by right-clicking Modules (in the solution) and selecting "Add Module." Select "svySearch" and click "OK."
- Drag a Text Field component onto the Form.
- Right-click the Form and select "Open in Script Editor."
- Create a new variable (JavaScript) to hold the search value:
var searchText = '';
- Back on the Form, in the Text Field properties:
- Set the "dataprovider" property to the Form variable you just created.
- Double-click to add a method for the onAction event.
- Click to create the method in "Form," name the method (e.g., onEnter), and click "Create private."
- Click "OK & Show."
- Add the following JavaScript to the JavaScript file to use the Servoy framework to implement searching bound data based on the text in the Text Field:
var search = scopes.svySearch.createSimpleSearch(foundset).setSearchText(searchText); search.setSearchAllColumns(); search.loadRecords(foundset);
Save and Launch the App
Save the form and JavaScript file, then click Run -> Launch NGClient to start the web app.
Download a free, 30-day trial of the CData API Driver for JDBC and start building NASA-connected apps with Servoy. Reach out to our Support Team if you have any questions.