1. Introduction

Goal

This tutorial aims to provide you with a step-by-step guide on how to integrate GitHub with a continuous integration/continuous deployment (CI/CD) service, in our case, Jenkins.

Learning Outcomes

By the end of this tutorial, you will be able to:

• Understand the basics of Continuous Integration and Continuous Deployment (CI/CD)
• Set up and configure Jenkins for your GitHub projects
• Implement a simple CI/CD pipeline with Jenkins and GitHub

Prerequisites

• Basic knowledge of Git and GitHub
• A GitHub account
• A basic understanding of Jenkins

2. Step-by-Step Guide

Continuous Integration and Continuous Deployment (CI/CD)

Continuous Integration (CI) is a development practice that involves developers integrating code into a shared repository frequently. Each integration can then be verified by an automated build and automated tests.

Continuous Deployment (CD) is a software release process that uses automated testing to validate if changes to a codebase are correct and stable for immediate autonomous deployment to a production environment.

Setting up Jenkins with GitHub

1. Install Jenkins: Follow the official Jenkins installation guide.

2. Create a New Job in Jenkins: Navigate to the Jenkins dashboard and click on New Item. Choose Freestyle project and provide a name for your job.

3. Configure GitHub in Jenkins: Under the Source Code Management section, select Git and enter your GitHub repository URL.

Configuring Webhooks in GitHub

Webhooks allow you to build or set up integrations that subscribe to certain events on GitHub.com.

1. Navigate to your GitHub repository, click on Settings > Webhooks > Add webhook.

2. Set Payload URL to your Jenkins environment followed by /github-webhook/ (e.g., http://your-jenkins-url/github-webhook/).

3. Choose Content type as application/json.

4. Select Just the push event, which triggers the Jenkins job whenever there's a push event in the repository.

3. Code Examples

# 1. Install Jenkins. On Ubuntu, you can use the following command:
sudo apt-get install Jenkins

# 2. Start Jenkins server. Usually, it starts automatically after installation. If not, use the following command:
sudo service Jenkins start

# 3. Open Jenkins on your web browser
http://localhost:8080

4. Summary

We've covered the basics of CI/CD, how to setup Jenkins with GitHub, and how to configure webhooks in GitHub. Your next steps could be to explore more about Jenkins and other CI/CD tools, and understand how to write automated tests for your CI/CD pipelines.

5. Practice Exercises

1. Exercise 1: Setup Jenkins on your local machine and integrate it with a simple Hello World repository on GitHub.

2. Exercise 2: Create a pipeline in Jenkins that builds your code and runs tests whenever there is a new push event in GitHub.

3. Exercise 3: Configure email notifications in Jenkins to be alerted whenever a build fails.

Solutions and Tips

1. Solution 1: Follow the step-by-step guide above.

2. Solution 2: In Jenkins job configuration, under Build section, add Execute Shell and write commands to build and test your code. Under Build Triggers, select GitHub hook trigger for GITScm polling.

3. Solution 3: In Jenkins job configuration, under Post-build Actions, add E-mail Notification and enter the recipient email address. Make sure the Jenkins email notification plugin is installed and SMTP server is configured in Manage Jenkins > Configure System > E-mail Notification.