Why CI/CD?

Continuous Integration (CI) and Continuous Deployment (CD) are essential practices in modern software development, enabling teams to automate the testing and deployment of applications. Kubernetes, an open-source platform for managing containerized workloads and services, has become the go-to solution for deploying, scaling, and managing applications. Integrating CI/CD pipelines with Kubernetes can significantly enhance the efficiency and reliability of software delivery processes. In this blog post, we’ll explore how to implement CI/CD with Kubernetes using two powerful tools: Argo for continuous deployment and Harbor as a container registry.

Understanding CI/CD and Kubernetes

Before diving into the specifics, let’s briefly understand what CI/CD and Kubernetes are:

• Continuous Integration (CI): A practice where developers frequently merge their code changes into a central repository, after which automated builds and tests are run. The main goals of CI are to find and address bugs quicker, improve software quality, and reduce the time it takes to validate and release new software updates.
• Continuous Deployment (CD): The next step after continuous integration, where all code changes are automatically deployed to a staging or production environment after the build stage. This ensures that the codebase is always in a deployable state.
• Kubernetes: An open-source system for automating deployment, scaling, and management of containerized applications. It groups containers that make up an application into logical units for easy management and discovery.

Why Use Argo and Harbor with Kubernetes?

• Argo CD: A declarative, GitOps continuous delivery tool for Kubernetes. Argo CD facilitates the automated deployment of applications to specified target environments based on configurations defined in a Git repository. It simplifies the management of Kubernetes resources and ensures that the live applications are synchronized with the desired state specified in Git.
• Harbor: An open-source container image registry that secures artifacts with policies and role-based access control, ensures images are scanned and free from vulnerabilities, and signs images as trusted. Harbor integrates well with Kubernetes, providing a reliable location for storing and managing container images.

Implementing CI/CD with Kubernetes Using Argo and Harbor

Step 1: Setting Up Harbor as Your Container Registry

1. Install Harbor: First, you need to install Harbor on your Kubernetes cluster. You can use Helm, a package manager for Kubernetes, to simplify the installation process. Ensure you have Helm installed and then add the Harbor chart repository:

   helm repo add harbor https://helm.goharbor.io
   helm install my-harbor harbor/harbor

2. Configure Harbor: After installation, configure Harbor by accessing its web UI through the exposed service IP or hostname. Set up projects, users, and access controls as needed.
3. Push Your Container Images: Build your Docker images and push them to your Harbor registry. Ensure your Kubernetes cluster can access Harbor and pull images from it.

   docker tag my-app:latest my-harbor-domain.com/my-project/my-app:latest
   docker push my-harbor-domain.com/my-project/my-app:latest

Step 2: Setting Up Argo CD for Continuous Deployment

1. Install Argo CD: Install Argo CD on your Kubernetes cluster. You can use the following commands to create the necessary resources:

   kubectl create namespace argocd
   kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

2. Access Argo CD: Access the Argo CD UI by exposing the Argo CD API server service. You can use port forwarding:

   kubectl port-forward svc/argocd-server -n argocd 8080:443

Then, access the UI through http://localhost:8080.

3. Configure Your Application in Argo CD: Define your application in Argo CD, specifying the source (your Git repository) and the destination (your Kubernetes cluster). You can do this through the UI or by applying an application manifest file.

   apiVersion: argoproj.io/v1alpha1
   kind: Application
   metadata:
     name: my-app
     namespace: argocd
   spec:
     project: default
     source:
       repoURL: 'https://my-git-repo.com/my-app.git'
       path: k8s
       targetRevision: HEAD
     destination:
       server: 'https://kubernetes.default.svc'
       namespace: my-app-namespace

4. Deploy Your Application: Once configured, Argo CD will automatically deploy your application based on the configurations in your Git repository. It continuously monitors the repository for changes and applies them to your Kubernetes cluster, ensuring that the deployed applications are always up-to-date.
5. Monitor and Manage Deployments: Use the Argo CD UI to monitor the status of your deployments, visualize the application topology, and manage rollbacks or manual syncs if necessary.

Wrapping it all up

Integrating CI/CD pipelines with Kubernetes using Argo for continuous deployment and Harbor as a container registry can streamline the process of building, testing, and deploying applications. By leveraging these tools, teams can achieve faster development cycles, improved reliability, and better security practices. Remember, the key to successful CI/CD implementation lies in continuous testing, monitoring, and feedback throughout the lifecycle of your applications.

Want more? Just ask in the comments.