Local Git-Jenkins-Docker Pipeline on Ubuntu

Overview

This repository provides a guide and configuration files to set up a local Continuous Integration/Continuous Deployment (CI/CD) pipeline using Git, Jenkins, and Docker on an Ubuntu EC2 instance. The pipeline is designed to automatically build and deploy a Dockerized Python web application whenever changes are pushed to the associated Git repository.

Prerequisites

1. EC2 Instance: Create an Ubuntu EC2 instance on AWS.

2. Docker Installation: Install Docker on the Ubuntu instance using the provided script.

   curl -fsSL https://get.docker.com -o get-docker.sh
   sh get-docker.sh

3. Java Installation: Install OpenJDK 17 (Java Runtime Environment).

   sudo apt install openjdk-17-jre

4. Jenkins Installation: Set up Jenkins on the instance.

   # Add Jenkins Repository to Sources List
   echo deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] https://pkg.jenkins.io/debian binary/ | sudo tee /etc/apt/sources.list.d/jenkins.list > /dev/null
   
   # Update and Install Jenkins
   sudo apt-get update
   sudo apt-get install jenkins

   if the above installtion doesn't work, get the recent release installation guide from jenkins documentation.

5. Firewall Configuration: Allow traffic on port 8080 for Jenkins, SSH connections, and port 8000 for container communication.

   sudo ufw allow 8080
   sudo ufw allow OpenSSH
   sudo ufw allow 8000
   sudo ufw enable

6. Jenkins Configuration:

   • Start Jenkins service and check its status.
   • Retrieve the initialAdminPassword for Jenkins setup.

   sudo systemctl start jenkins.service
   sudo systemctl status jenkins
   sudo cat /var/lib/jenkins/secrets/initialAdminPassword

7. Docker Hub Account: Create a Docker Hub account and login to Docker on the Ubuntu instance.

   sudo docker login -u <username> -p <password>

8. Jenkins-Docker Integration: Add the Jenkins user to the docker group for Docker access.

   sudo usermod -aG docker jenkins
   sudo systemctl restart jenkins

Jenkins Setup

1. Open <Public_IP_Address_of_EC2_Instance>:8080 in a browser.

2. Log in with the initialAdminPassword obtained earlier.

3. Install suggested plugins and set up a new username and password.

4. Setup credentials in Jenkins, including Docker Hub username and password.

5. Make necessary changes in the Jenkinsfile, setting credentials id and Docker username.

Local Development

1. Create a pipeline in Jenkins, specifying the GitHub repository and branch.

2. Build the pipeline to execute the defined stages.

3. Open <Public_IP_Address_of_EC2_Instance>:8000 in a browser to view the application.

Making Changes

To see the pipeline in action, make changes to the hello.html file in the templates folder of the repository. Commit the changes, and within a minute, the updates should reflect on the end page.