Scripted Pipelines

(this post if part of the material I cover in my devops course)

Scripted pipelines are using Groovy language syntax to achieve part of the requirements for a pipeline.
The other option (that we'll cover in another post) is Declarative syntax.

Scripted Pipeline example

• Create a pipeline as explained in pipelines-primer-1 but select Scripted Pipeline from the dropdown selection:

 1node {
 2    def mvnHome
 3    stage('Preparation') { // for display purposes
 4        // Get some code from a GitHub repository
 5        git 'https://github.com/jglick/simple-maven-project-with-tests.git'
 6        // Get the Maven tool.
 7        // ** NOTE: This 'M3' Maven tool must be configured
 8        // **       in the global configuration.
 9        mvnHome = tool 'M3'
10    }
11    stage('Build') {
12        // Run the maven build
13        withEnv(["MVN_HOME=$mvnHome"]) {
14            if (isUnix()) {
15                sh '"$MVN_HOME/bin/mvn" -Dmaven.test.failure.ignore clean package'
16            } else {
17                bat(/"%MVN_HOME%\bin\mvn" -Dmaven.test.failure.ignore clean package/)
18            }
19        }
20    }
21    stage('Results') {
22        junit '**/target/surefire-reports/TEST-*.xml'
23        archiveArtifacts 'target/*.jar'
24    }
25}

Run the scripted pipeline example

• this pipeline is not going to run until you create a maven instalation (tool) called M3
• Go to Dashboard--> Manage Jenkins --> Tools
• Scroll to the bottom of this window
• Add maven, call it M3
• Go ahead and run the pipeline

Scripted Pipeline characteristics

• the main component is node (vs. pipeline for declarative pipelines)
• There are stages, simmilar to those used in declarative syntax
• There are no steps, and these are actually implemented as Groovy lines
• There us a global declaration of a variable (mvnHome) later used to create an environment variable
• There are Groovy constructs (if clauses, function calls) used throughout the pipeline.