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How to write a Jenkinsfile to build a Maven project and deploy to Apache Tomcat webserver

Prerequisites

  • maven, Deploy to container plugins should be installed in Jenkins.
  • Configure specific version of maven in Jenkins Global Tool Configuration

I have a sample hello-world maven project in github hello-world

Fork this project hello-world and update the required fields in the Jenkinsfile 03-Jenkinsfile-deploy-to-tomcat

Maven is a build tool used to compile, test and package the application developed using Java programming language.

Jenkinsfile

pipeline {
  agent any
  tools {
    maven 'maven-3.6.3' 
  }
  stages {
    stage ('Build') {
      steps {
        sh 'mvn clean package'
      }
    }
    stage ('Deploy') {
      steps {
        script {
          deploy adapters: [tomcat9(credentialsId: 'tomcat_credential', path: '', url: 'http://dayal-test.letspractice.tk:8081')], contextPath: '/pipeline', onFailure: false, war: 'webapp/target/*.war' 
        }
      }
    }
  }
}

In the tools block we have used maven definition to refer the maven installation maven-3.6.3 configured in Jenkins Global tool configuration.

In the stages block we have created two stages Build and Deploy.

In the Build stage we are executing mvn clean package command to compile and package the java application.

It will compile the java code and generate the package in targets folder.

jenkins

In the Deploy stage we are using the Deploy to container plugin to deploy the hello-world.war file to tomcat webserver.

Parameters passed to Deploy to container plugin definition.

  • credentialsId: ‘tomcat_credential’ –> Store the tomcat username and password in Jenkins credentials and pass the tomcat credential id here. I have stored the tomcat credentials in Jenkins and created the id as tomcat_credential

    Before storing the credentials in jenkins, create a user in Tomcat with manager-script role.

    To create users in Tomcat, open the file /var/lib/tomcat9/conf/tomcat-users.xml
    sudo vi /var/lib/tomcat9/conf/tomcat-users.xml

    Go to end of the file and paste the following lines inside tomcat-users block and save it.


    <role rolename="manager-script"/><br><user username="deployer" password="deployer" roles="manager-script"/>


    jenkins


    Here we have defined one role manager-script and created one user deployer and assigned the manager-script role to the deployer user.

    Then restart the tomcat9


    sudo systemctl restart tomcat9

  • url: ‘http://152.70.71.239:8080/‘ –> Your tomcat url
  • contextPath: ‘/pipeline’ –> Context path to deploy in Tomcat
  • onFailure: false –> Flag used to control the deployment, I dont want to deploy If my pipeline JOb fails, thats why I am setting onFailure flag to false
  • war: ‘target/*.war’ –> Your war file name
tomcat

References