Skip to content

Create Pipeline (Jenkinsfile)

In this tutorial, I explain: - How to create a Pipeline job in Jenkins - Where to reference the Jenkinsfile from - Difference between inline script vs Jenkinsfile from SCM - How Jenkins reads and executes the Jenkinsfile - How to trigger and validate the pipeline run

Create a GitHub repository with a sample Java Maven project How to create a GitHub repository and push a sample Java 21 Maven Project

Jenkinsfile is a file, where you can write all the build commands and store the file in the GitHub repository, then Jenkins Pipeline can reference it to execute the commands

Difference: Inline Script vs Pipeline from SCM

In the previous tutorial, we used Pipeline Script (Inline), where the code is pasted directly into Jenkins UI. In this tutorial, we use Pipeline Script from SCM, where Jenkins reads the Jenkinsfile from a Git repository.

Feature Inline Script Pipeline from SCM
Location Stored in Jenkins Job Config Stored in Git Repository
Versioning No version control Versioned with App Code
Collaboration Hard to review changes Easy via Pull Requests
Best For Quick testing / Experiments Production Pipelines

Create a Jenkinsfile named 01-Jenkinsfile-helloworld inside cicd

The Jenkinsfile can be named to anything like this Jenkinsfile-dev, 01-Jenkinsfile-helloworld

mkdir cicd
ls -l
cd cicd
vi 01-Jenkinsfile-helloworld
ls -l

pipeline {
  agent any
  stages {
    stage ('Build') {
      steps {
        sh 'echo Hello Build stage'
      }
    }
    stage ('Test') {
      steps {
        sh 'echo hello Test stage'
      }
    }
  }
}

Reference: Pipeline Syntax

vignesh ~/code/devopspilot1/hello-world-java [main] $ ll
total 16
-rw-r--r-- 1 vignesh  staff   762 Jul 12 22:56 README.md
-rw-r--r-- 1 vignesh  staff  1414 Jul 12 22:56 pom.xml
drwxr-xr-x  4 vignesh  staff   128 Jul 12 22:56 src

vignesh ~/code/devopspilot1/hello-world-java [main] $ mkdir cicd

vignesh ~/code/devopspilot1/hello-world-java [main] $ ls -l
total 24
-rw-r--r-- 1 vignesh  staff   210 Jul 15 19:31 01-Jenkinsfile-helloworld
-rw-r--r-- 1 vignesh  staff   762 Jul 12 22:56 README.md
drwxr-xr-x  2 vignesh  staff    64 Jul 15 19:32 cicd
-rw-r--r-- 1 vignesh  staff  1414 Jul 12 22:56 pom.xml
drwxr-xr-x  4 vignesh  staff   128 Jul 12 22:56 src

vignesh ~/code/devopspilot1/hello-world-java [main] $ cd cicd

vignesh ~/code/devopspilot1/hello-world-java/cicd [main] $ vi 01-Jenkinsfile-helloworld

vignesh ~/code/devopspilot1/hello-world-java/cicd [main] $ ls -l
total 8
-rw-r--r-- 1 vignesh  staff  210 Jul 15 19:34 01-Jenkinsfile-helloworld

Check Git status

cd ..
git status

vignesh ~/code/devopspilot1/hello-world-java/cicd [main] $ cd ..

vignesh ~/code/devopspilot1/hello-world-java [main] $ git status
On branch main
Your branch is up to date with 'origin/main'.

Untracked files:
  (use "git add <file>..." to include in what will be committed)
    cicd/

nothing added to commit but untracked files present (use "git add" to track)

Add the file and push it to the GitHub repository

git add .
git status
git commit -m "Added Jenkinsfile 01-Jenkinsfile-helloworld"
git push origin main

vignesh ~/code/devopspilot1/hello-world-java [main] $ git add .

vignesh ~/code/devopspilot1/hello-world-java [main] $ git status
On branch main
Your branch is up to date with 'origin/main'.

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
    new file:   cicd/01-Jenkinsfile-helloworld

vignesh ~/code/devopspilot1/hello-world-java [main] $ git commit -m "Added Jenkinsfile 01-Jenkinsfile-helloworld" 
[main c548f08] Added Jenkinsfile 01-Jenkinsfile-helloworld
 1 file changed, 15 insertions(+)
 create mode 100644 cicd/01-Jenkinsfile-helloworld

vignesh ~/code/devopspilot1/hello-world-java [main] $ git push origin main
Enumerating objects: 5, done.
Counting objects: 100% (5/5), done.
Delta compression using up to 10 threads
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 455 bytes | 455.00 KiB/s, done.
Total 4 (delta 1), reused 0 (delta 0), pack-reused 0
remote: Resolving deltas: 100% (1/1), completed with 1 local object.
To https://github.com/devopspilot1/hello-world-java.git
   27d7fcb..c548f08  main -> main

Verify cicd/01-Jenkinsfile-helloworld file is pushed to the GitHub repository

Goto Jenkins dashboard, click on New Item

Enter the Pipeline name 01-hello-world-java, select Pipeline, and then click OK

Select the Pipeline section, under Definition choose Pipeline script from SCM

From SCM choose Git and enter your GitHub repository URL

Under Branch Specifier change the branch name to main

Under Script Path enter the Jenkfinsfile path cicd/01-Jenkinsfile-helloworld and click on Save

Click on Build Now

Goto Console Output, first it obtained the Jenkinsfile cicd/01-Jenkinsfile-helloworld from the GitHub repository, then clones the GitHub Repository and executed the commands defined in the stages

In Jenkinsfile you had 2 stages Build and Test, in both the stages it executes the sh step to execute the echo commands

How Jenkins Reads and Executes

When you clicked Build Now: 1. Jenkins connected to the Git URL provided. 2. It searched for the file path cicd/01-Jenkinsfile-helloworld. 3. It read the file contents. 4. It recognized the pipeline { ... } syntax. 5. It then executed the stages sequentially (Build -> Test).

Important Tips

Tip

Single Source of Truth: Storing the pipeline in SCM means your build logic is versioned alongside your application code. This allows you to roll back build logic just like you roll back code changes.

Important

Branching: When using "Pipeline script from SCM", Jenkins will check out the specific branch you configured. If you are using Multibranch Pipelines (advanced), Jenkins can automatically discover Jenkinsfiles in all branches.

🧠 Quick Quiz — Pipeline from SCM

#

What does "Pipeline script from SCM" allow you to do?