Need For Pipelines

• Consider a Repository (https://github.com/GitPracticeRepo/spring-petclinic) where there are multiple branches and User is expected to create multiple projects for building each branch.
• To achieve this we create multiple projects every time manually configuring the options
• For master branch, you are supposed to do clean build (mvn clean package) and sprint-1 branch incremental build (mvn package)

Jenkins Pipeline

• Is a scripted way of defining jenkins job.
• Jenkins job can be defined in git repository in one file.
• Lets try this.
• Navigate to code repository and create a file Jenkinsfile with following content

node {

   stage('SCM') {
      // git clone
	  git 'https://github.com/GitPracticeRepo/spring-petclinic.git'
   }
   
   stage ('build the packages') {
      // mvn package
	  sh 'mvn package'
   }

   
   
   stage ('archival') {
     // archiving artifacts
	 archive 'target/*.jar'
   }

}

• Now open Jenkins and create a pipeline project as shown below

• In Jenkins Pipeline the script is written by using groovy language (Java Based Language) with this we get the following benefits
  • Customization of builds become simpler
  • Creating reusable build library is possible
  • Even in the case of plugins what we generally call from Script is functions.