Connect to Stack Exchange Data in JRuby

JRuby is a high-performance, stable, fully threaded Java implementation of the Ruby programming language. The CData JDBC Driver for Stack Exchange makes it easy to integrate connectivity to live Stack Exchange data in JRuby. This article shows how to create a simple JRuby app that connects to Stack Exchange data, executes a query, and displays the results.

Configure a JDBC Connection to Stack Exchange Data

Before creating the app, note the installation location for the JAR file for the JDBC Driver (typically C:\Program Files\CData\CData JDBC Driver for Stack Exchange\lib).

JRuby natively supports JDBC, so you can easily connect to Stack Exchange and execute SQL queries. Initialize the JDBC connection with the getConnection function of the java.sql.DriverManager class.

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

Stack Exchange API Profile Settings

Register an application on StackApps to obtain an API Key. The Site property specifies which Stack Exchange site to query (e.g., stackoverflow).

Built-in Connection String Designer

For assistance in constructing the JDBC URL, use the connection string designer built into the Stack Exchange 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.

Below is a typical JDBC connection string for Stack Exchange:

jdbc:api:Profile=C:\profiles\StackExchange.apip;ProfileSettings='APIKey=your_api_key;Site=stackoverflow';

Create a JRuby App with Connectivity to Stack Exchange Data

Create a new Ruby file (for example: APISelect.rb) and open it in a text editor. Copy the following code into your file:

require 'java'
require 'rubygems'
require 'C:/Program Files/CData/CData JDBC Driver for Stack Exchange 2018/lib/cdata.jdbc.api.jar'

url = "jdbc:api:Profile=C:\profiles\StackExchange.apip;ProfileSettings='APIKey=your_api_key;Site=stackoverflow';"
conn = java.sql.DriverManager.getConnection(url)
stmt = conn.createStatement
rs = stmt.executeQuery("SELECT AnswerId, CreationDate FROM Answers")
while (rs.next) do
 puts rs.getString(1) + ' ' + rs.getString(2)
end

With the file completed, you are ready to display your Stack Exchange data with JRuby. To do so, simply run your file from the command line:

jruby -S APISelect.rb

Writing SQL-92 queries to Stack Exchange allows you to quickly and easily incorporate Stack Exchange data into your own JRuby applications. Download a free trial today!