Mighty Middleware: Using Hudson as CI tool on WLS

One of the key concept of Service Oriented Architechture is that services are no longer built to last, but rather built to change.

In software engineering, continuous integration (CI) implements continuous processes of applying quality control — small pieces of effort, applied frequently. Continuous integration aims to improve the quality of software, and to reduce the time taken to deliver it, by replacing the traditional practice of applying quality control after completing all development.

Now if we follow SOA principles, then the design and implementation should be optimized. However what SOA doesn't address is how we build, deploy, test and finally released that code into production.

This is where a CI tool (details of CI can be found here) comes very useful.

Hudson is such a continuous integration (CI) tool written in Java, which runs in a servlet container, such as Apache Tomcat or the WebLogic application server. It supports SCM tools including CVS, Subversion, Git and Clearcase and can execute Apache Ant and Apache Maven based projects, as well as arbitrary shell scripts and Windows batch commands.

In the following steps we will see how to configure Hudson on WebLogic (Due to Weblogic's class loading structure, if the hudson.war is directly deployed, the application will fail to startup. This is to because there are jar conflicts between Hudson and Weblogic. To get around the issue, we use the FilteringClassLoader mechanism so that specific hudson jars get priority in the classpath over Weblogic's jars).

Versions
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Hudson: 2.2.0
WebLogic: 10.3.1 (11g R1)

Steps:
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1> Downnload Hudson Binary (2.2.0) from here
2> Unzip downloaded hudson.zip
3> Go inside the unzipped location and make a .war file from the content (jar -cvf hudson.war .)
4> copy the hudson war to a directory (e.g. E:\installers\hudson) and create another folder (META-INF) in it.
5> add application.xml and weblogic-application.xml in the META-INF directory

application.xml
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