Cloud DevOps Admin Guide

📢Building a Pull-Based DevOps Pipeline with GitHub Actions and Argo CD🔥

🎈In modern software development, establishing an efficient and reliable DevOps pipeline is crucial for ensuring smooth application delivery and continuous deployment.
💊In this article, we’ll explore a pull-based DevOps pipeline using GitHub Actions for building and Argo CD as the GitOps operator for deployment.
💊This pipeline enables seamless development, containerization, and deployment of web applications.

🚩The data flows through the scenario as follows:

1️⃣ App Code Development:

The process begins with developers writing and modifying code using an Integrated Development Environment (IDE) such as Visual Studio Code. This is where the core functionality and features of the web application are developed and tested.

2️⃣ Code Commitment to GitHub Repository:

Once the code is ready for the next stage, it is committed to a GitHub repository. GitHub provides a collaborative platform that supports version control and facilitates seamless collaboration among team members.

3️⃣ GitHub Actions for Build & push:

GitHub Actions is a powerful automation tool that allows developers to define custom workflows triggered by events, such as code commits. In our pipeline, we leverage GitHub Actions to build a container image from the app code. This process typically involves using a Dockerfile to specify the build steps and dependencies required for the application.

After successfully building the container image, GitHub Actions pushes it to an Azure Container Registry (ACR). ACR provides a secure and private repository for storing container images.

4️⃣ Updating Kubernetes Manifest Deployment File.
➡With the container image available in ACR, GitHub Actions updates a Kubernetes manifest deployment file. This file specifies the desired state of the application’s deployment on a Kubernetes cluster. The update involves setting the current image version based on the version number of the container image in ACR. This step ensures that the deployment references the latest version of the container image.

5️⃣ Argo CD pulls from the Git repository.
➡Argo CD, a GitOps operator, continuously monitors a Git repository for changes. When a new commit is detected, Argo CD pulls the updated deployment manifests from the repository. This GitOps approach ensures that the desired state of the application is defined in version-controlled manifests, enabling easier rollbacks, reproducibility, and auditability.

6️⃣ Argo CD deploys the app to the AKS cluster.
➡Once Argo CD pulls the updated deployment manifests, it orchestrates the deployment process to an Azure Kubernetes Service (AKS) cluster. Argo CD compares the desired state defined in the deployment manifests with the current state of the cluster and ensures that the application is deployed and configured accordingly. It handles the synchronization of resources, rolling updates, and rollbacks, if necessary, to maintain the desired state of the application.

Conclusion:

✅By combining the power of GitHub Actions for building and Argo CD for deployment, we’ve established a robust pull-based DevOps pipeline for web application development.
✅This pipeline ensures that changes in the app code trigger an automated build, followed by seamless deployment to an AKS cluster.
✅The pull-based approach, along with version-controlled manifests and container images, enhances traceability, reproducibility, and consistency throughout the development lifecycle.
✅With this pipeline in place, developers can focus on writing code while maintaining a smooth and reliable application delivery process.

By Sreekanth Thummala