🚀 CI/CD Workflow Overview

📌 1. Code Commit & Version Control

Version Control Systems (VCS) help manage code changes, collaborate with teams, and track modifications, ensuring smooth development and rollback capabilities when needed.

🔹 Popular VCS Tools

• Git 🟢 - Distributed version control system widely used in software development.
• GitHub 🟣 - Cloud-based Git repository hosting service offering collaboration and CI/CD features.
• GitLab 🔵 - Integrated DevOps platform with built-in CI/CD and security tools.
• Bitbucket 🟠 - Atlassian's Git repository with integration into Jira and CI/CD pipelines.

🔹 Git Workflow & Branching Strategy

Developers follow a standard Git workflow to manage changes effectively.

git clone <repository-url>
git checkout -b feature-branch
git add .
git commit -m "Added new feature"
git push origin feature-branch

Branching Strategies

• Main Branch: The stable branch that holds production-ready code.
• Develop Branch: Used for integrating new features before merging into the main branch.
• Feature Branch: Created for individual features or bug fixes.
• Release Branch: Prepared for final testing before deployment.
• Hotfix Branch: Used for critical bug fixes in production.

Once the feature is ready, a Pull Request (PR) is created for code review and merging into the develop or main branch.

🔹 Example Branching Workflow

1. A developer clones the repository and creates a new feature branch:

   git clone https://github.com/example/repo.git
   git checkout -b feature-login
2. They make changes and commit the code:

   git add .
   git commit -m "Implemented user login"
3. Push the feature branch to the remote repository:

   git push origin feature-login
4. Open a Pull Request (PR) to merge feature-login into the develop branch.
5. After approval, the branch is merged and deployed through the CI/CD pipeline.

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⚙️ 2. Continuous Integration (CI) Process

CI automates the process of building, testing, and verifying code before merging.

🔹 CI Tools

• Jenkins 🟡 - Open-source automation server for CI/CD pipelines.
• GitHub Actions 🟢 - Native CI/CD for GitHub repositories.
• GitLab CI/CD 🔵 - Integrated CI/CD system within GitLab.
• CircleCI 🔴 - Cloud-based CI/CD solution with fast pipelines.

🔹 CI Workflow

1. Developer Pushes Code to Git 📤
2. CI System Detects Changes & Triggers a Build ⚙️
3. Automated Unit & Integration Tests Run 🧪
4. Static Code Analysis & Code Quality Checks 🔍
5. Build Artifacts (JAR, Docker Images) Created 📦
6. Notifications Sent to Developers 📩

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🚀 3. Continuous Delivery vs. Continuous Deployment

CI/CD can be categorized into two approaches based on automation levels.

Aspect	Continuous Delivery	Continuous Deployment
Definition	Code is automatically tested and ready for manual deployment	Code is automatically tested and deployed to production
Deployment Trigger	Manual Approval Required	Fully Automated
Risk Level	Lower ✅	Higher 🚀
Use Cases	Enterprise, Banking, Regulated Environments	SaaS, Web Apps, Rapid Development

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📊 4. Deployment Pipelines

A CI/CD pipeline automates software deployment through several stages.

🔹 Pipeline Stages

1. Source Code Management (SCM) 📝 - Fetch code from Git repositories.
2. Build & Compile ⚙️ - Convert source code into executable artifacts using tools like Maven, Gradle, or Webpack.
3. Automated Testing 🧪 - Run unit, integration, and UI tests using JUnit, Selenium, Jest.
4. Security Scanning 🔒 - Perform vulnerability analysis using SonarQube, Snyk.
5. Artifact Storage 📦 - Store binaries in repositories like Docker Hub, Nexus, or AWS S3.
6. Deployment to Staging 🏗️ - Deploy code to a staging environment using AWS, Kubernetes, Terraform, or Ansible.
7. Approval & Manual Testing ✅ - Conduct manual verification before production deployment.
8. Production Deployment 🚀 - Deploy code to live servers using Blue-Green or Canary Deployment strategies.

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🌟 Benefits of CI/CD

• ✅ Faster Releases - Automate code integration and deployment.
• ✅ Fewer Errors - Catch issues early with automated testing.
• ✅ Higher Code Quality - Enforce best practices with CI checks.
• ✅ Continuous Feedback - Get real-time insights into build status.
• ✅ Better Collaboration - Enable seamless teamwork across developers, testers, and operations.

By implementing a robust CI/CD pipeline, teams can achieve faster, more reliable, and efficient software delivery 🚀.

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💡 Example CI/CD Pipeline using Jenkins

pipeline {
    agent any
    stages {
        stage('Checkout Code') {
            steps {
                git 'https://github.com/example/repo.git'
            }
        }
        stage('Build') {
            steps {
                sh 'mvn clean package'
            }
        }
        stage('Test') {
            steps {
                sh 'mvn test'
            }
        }
        stage('Deploy') {
            steps {
                sh 'kubectl apply -f deployment.yaml'
            }
        }
    }
}