Docker image as artifact in Jenkins - Mini Project: Build & Apply

Docker Image as Artifact in Jenkins Pipeline

📖 Scenario: You are working as a DevOps engineer. Your team wants to build a Docker image from a simple Dockerfile and save this image as an artifact in Jenkins. This will help the team reuse the image later without rebuilding it every time.

🎯 Goal: Create a Jenkins pipeline script that builds a Docker image from a Dockerfile, tags it with a specific name, and archives the image as an artifact.

📋 What You'll Learn

Create a Dockerfile with a simple base image

Write a Jenkins pipeline script

Build a Docker image with a specific tag

Save the Docker image as a tar file

Archive the tar file as a Jenkins artifact

💡 Why This Matters

🌍 Real World

Saving Docker images as artifacts in Jenkins pipelines helps teams reuse images without rebuilding, speeding up deployments and ensuring consistency.

💼 Career

This skill is essential for DevOps engineers and CI/CD pipeline developers who automate container builds and deployments.

1

Create a simple Dockerfile

Create a file named Dockerfile with the following content exactly:
FROM alpine:3.18
CMD ["echo", "Hello from Docker"]

Jenkins

# Your Dockerfile content here

Need a hint?

This Dockerfile uses Alpine Linux as the base image and prints a message when run.

2

Define Docker image name variable in Jenkinsfile

In your Jenkins pipeline script, create a variable called imageName and set it to myapp:test.

Jenkins

// Define Docker image name variable
// Your code here

Need a hint?

Use def imageName = 'myapp:test' to define the variable.

3

Build and save Docker image in Jenkins pipeline

Add a stage named 'Build' in the Jenkins pipeline that runs shell commands to build the Docker image using docker build -t myapp:test . and then save it as myapp_test.tar using docker save -o myapp_test.tar myapp:test.

Jenkins

def imageName = 'myapp:test'

// Add a stage named 'Build' to build and save the Docker image
// Your code here

Need a hint?

Use sh steps inside the stage('Build') to run the Docker commands.

4

Archive the Docker image tar file as artifact

Add a stage named 'Archive' in the Jenkins pipeline that archives the file myapp_test.tar as an artifact using archiveArtifacts 'myapp_test.tar'.

Jenkins

def imageName = 'myapp:test'

pipeline {
    agent any
    stages {
        stage('Build') {
            steps {
                sh "docker build -t ${imageName} ."
                sh "docker save -o myapp_test.tar ${imageName}"
            }
        }
        // Add a stage named 'Archive' to archive the Docker image tar file
        // Your code here
    }
}

Need a hint?

Use archiveArtifacts 'myapp_test.tar' inside the stage('Archive') to save the artifact.