Access CouchDB Data in Mule Applications Using the CData JDBC Driver

The CData JDBC Driver for CouchDB connects CouchDB data to Mule applications enabling read , write, update, and delete functionality with familiar SQL queries. The JDBC Driver allows users to easily create Mule applications to backup, transform, report, and analyze CouchDB data.

This article demonstrates how to use the CData JDBC Driver for CouchDB inside of a Mule project to create a Web interface for CouchDB data. The application created allows you to request CouchDB data using an HTTP request and have the results returned as JSON. The exact same procedure outlined below can be used with any CData JDBC Driver to create a Web interface for the hundreds of available data sources.

1. Create a new Mule Project in Anypoint Studio.
2. Add an HTTP Connector to the Message Flow.
3. Configure the address for the HTTP Connector. 👁 Add and Configure the HTTP Connector
   
4. Add a Database Select Connector to the same flow, after the HTTP Connector.
5. Create a new Connection (or edit an existing one) and configure the properties.
   • Set Connection to "Generic Connection"
   • Select the CData JDBC Driver JAR file in the Required Libraries section (e.g. cdata.jdbc.apachecouchdb.jar). 👁 Adding the JAR file (Salesforce is shown).
     
   • Set the URL to the connection string for CouchDB

     Set the following to connect:

     • Url: The Url of your instance. For example: http://localhost:5984
     • User The Apache CouchDB user account used to authenticate.
     • Password The Apache CouchDB password associated with the authenticating user.

     Built-in Connection String Designer

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

     		java -jar cdata.jdbc.apachecouchdb.jar
     		

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

   • Set the Driver class name to cdata.jdbc.apachecouchdb.ApacheCouchDBDriver. 👁 A configured Database Connection (Salesforce is shown).
     
   • Click Test Connection.
6. Set the SQL Query Text to a SQL query to request CouchDB data. For example:

   SELECT MovieRuntime, MovieRating FROM Movies WHERE MovieRating = 'R'

   👁 Configure the Select object (Salesforce is Shown)
   
7. Add a Transform Message Component to the flow.
8. Set the Output script to the following to convert the payload to JSON:

   %dw 2.0
   output application/json
   ---
   payload
    

   👁 Add the Transform Message Component to the Flow
   
9. To view your CouchDB data, navigate to the address you configured for the HTTP Connector (localhost:8081 by default): http://localhost:8081. The CouchDB data is available as JSON in your Web browser and any other tools capable of consuming JSON endpoints.

At this point, you have a simple Web interface for working with CouchDB data (as JSON data) in custom apps and a wide variety of BI, reporting, and ETL tools. Download a free, 30 day trial of the JDBC Driver for CouchDB and see the CData difference in your Mule Applications today.