Connect to GraphQL Data in JRuby

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

Configure a JDBC Connection to GraphQL 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 GraphQL\lib).

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

You must specify the URL of the GraphQL service. The driver supports two types of authentication:

• Set AuthScheme to Basic. You must specify the User and Password of the GraphQL service.
• Take a look at the OAuth section in the Help documentation for detailed instructions.

Built-in Connection String Designer

For assistance in constructing the JDBC URL, use the connection string designer built into the GraphQL JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

java -jar cdata.jdbc.graphql.jar

Fill in the connection properties and copy the connection string to the clipboard.

Below is a typical JDBC connection string for GraphQL:

jdbc:graphql:AuthScheme=Basic;User=username;Password=password;URL=https://mysite.com;InitiateOAuth=GETANDREFRESH;

Create a JRuby App with Connectivity to GraphQL Data

Create a new Ruby file (for example: GraphQLSelect.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 GraphQL 2018/lib/cdata.jdbc.graphql.jar'

url = "jdbc:graphql:AuthScheme=Basic;User=username;Password=password;URL=https://mysite.com;InitiateOAuth=GETANDREFRESH;"
conn = java.sql.DriverManager.getConnection(url)
stmt = conn.createStatement
rs = stmt.executeQuery("SELECT Name, Email FROM Users")
while (rs.next) do
 puts rs.getString(1) + ' ' + rs.getString(2)
end

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

jruby -S GraphQLSelect.rb

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