At my company we’re currently moving away from developing large desktop applications to developing smaller web applications. Changing our build-test-deploy processes is also part of that transition. After using Jenkins for a long time merely for continuous integration, I wanted to see what it takes to set up a continuous deployment pipeline. In this short post I’ll describe the steps to extend a Jenkins job to automatically deploy a built war file to a Tomcat instance. In future posts I intend to also elaborate on adding automated tests using Cucumber and or Selenium to the Jenkins build.
Step 0. Prerequisites
For the next steps I assume that you already have Tomcat up and running, you also have Jenkins up and running, have administrator privileges, and you have set up a job in Jenkins that produces a war file.
Step 1. Install Jenkins plugin
Open your favorite browser and navigate to Jenkins. Log in and select “Manage Jenkins” followed by “Manage Plugins”. Select the “Available” tab, locate the “Deploy to container” plugin and install it.
Step 2. Edit tomcat-users.xml
In order for Tomcat to accept remote deployments, you have to add a user with the role
manager-script. To do so, edit the file
../conf/tomcat-users.xml and add the following line:
<user username=“deployer” password=“deployer” roles=“manager-script” />
Step 3. Edit the Jenkins job
Back in Jenkins, go to your job and select “Configure”. Next, scroll down to the bottom of the page to the “Post-build Actions”. Select the option “Deploy war/ear to a container” from the “Add post-build action” dropdown button. Fill in the new fields, e.g.:
For WAR/EAR files you can use wild cards, e.g.
The context path is the context path part of the URL under which your application will be published in Tomcat.
Select the appropriate Tomcat version from the Container dropdown box (note that you can also deploy to Glassfish or JBoss using this Jenkins plugin).
For the manager’s user name and password just copy over what you’ve entered in the tomcat-users.xml file.
The Tomcat URL is the base URL through which your Tomcat instance can be reached.
Finally, don’t forget to save the configuration.
Step 4. Run the Job project and verify the end results
Schedule a build for your job in Jenkins. If you check out the log file you should see one or more lines near the end indicating that the war file has been deployed, e.g.:
Deploying /home/maven/hudson/hudson-work/jobs/MyWebApp/workspace/trunk/target/MyWebApp-1.0-SNAPSHOT.war to container Tomcat 7.x Remote Redeploying [/home/maven/hudson/hudson-work/jobs/MyWebApp/workspace/trunk/target/MyWebApp-1.0-SNAPSHOT.war] Undeploying [/home/maven/hudson/hudson-work/jobs/MyWebApp/workspace/trunk/target/MyWebApp-1.0-SNAPSHOT.war] Deploying [/home/maven/hudson/hudson-work/jobs/MyWebApp/workspace/trunk/target/MyWebApp-1.0-SNAPSHOT.war] Finished: SUCCESS
If you check the logfiles in Tomcat (
catalina.out) you should also see that your application has been succesfully deployed.
Lastly, if you point your browser to the URL and context path you’ve specified in the job configuration in Jenkins (e.g., http://your-server:8080/mywebapp), you should be able to open your freshly deployed application.