Create a Data Access Object for Discourse Data using JDBI

JDBI is a SQL convenience library for Java that exposes two different style APIs, a fluent style and a SQL object style. The CData JDBC Driver for Discourse integrates connectivity to live Discourse data in Java applications. By pairing these technologies, you gain simple, programmatic access to Discourse data. This article explains how to build a basic Data Access Object (DAO) and the accompanying code to read Discourse data.

Create a DAO for the Discourse Backups Entity

The interface below declares the desired behavior for the SQL object to create a single method for each SQL statement to be implemented.

public interface MyBackupsDAO {
 //request specific data from Discourse (String type is used for simplicity)
 @SqlQuery("SELECT FROM Backups WHERE = :")
 String findBy(@Bind("") String );

 /*
 * close with no args is used to close the connection
 */
 void close();
}

Open a Connection to Discourse

Collect the necessary connection properties and construct the appropriate JDBC URL for connecting to Discourse.

The Discourse API uses API Key authentication.

Using API Key Authentication

Discourse requires API Key and Username for authentication. API Keys are generated in the Discourse Admin panel under the API section. You can create user-specific API keys or all-users API keys. Once you have obtained the API Key, set it along with the Domain and Username in the ProfileSettings connection property.

Example Connection string

Profile=C:\profiles\Discourse.apip;ProfileSettings='Domain=forum.example.com;APIKey=your_api_key;Username=your_username;'AuthScheme=APIKey;

Built-in Connection String Designer

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

A connection string for Discourse will typically look like the following:

jdbc:api:Profile=C:\profiles\Discourse.apip;ProfileSettings='Domain=forum.example.com;APIKey=your_api_key;Username=your_username;'AuthScheme=APIKey;

Use the configured JDBC URL to obtain an instance of the DAO interface. The particular method shown below will open a handle bound to the instance, so the instance needs to be closed explicitly to release the handle and the bound JDBC connection.

DBI dbi = new DBI("jdbc:api:Profile=C:\profiles\Discourse.apip;ProfileSettings='Domain=forum.example.com;APIKey=your_api_key;Username=your_username;'AuthScheme=APIKey;");
MyBackupsDAO dao = dbi.open(MyBackupsDAO.class);

//do stuff with the DAO

dao.close();

Read Discourse Data

With the connection open to Discourse, simply call the previously defined method to retrieve data from the Backups entity in Discourse.

//disply the result of our 'find' method
String = dao.findBy("");
System.out.println();

Since the JDBI library is able to work with JDBC connections, you can easily produce a SQL Object API for Discourse by integrating with the CData JDBC Driver for Discourse. Download a free trial and work with live Discourse data in custom Java applications today.