Automating Deployment of a Spring Boot Application to Azure Kubernetes Cluster with Github Actions

• Kubernetes has become a popular container orchestration platform, and Microsoft Azure provides a reliable and scalable managed Kubernetes service. Spring Boot, on the other hand, is a widely used Java framework for building web applications.
• In this article, we will explore how to deploy a Spring Boot application to an Azure Kubernetes cluster using Github Actions, a powerful automation tool for software development workflows.
• Next, we will create a Github repository for our application and set up Github Actions to automate the deployment process. Finally, we will test our deployment and make sure our application is up and running on the Kubernetes cluster.

Dockerize the Spring Boot Application

• To run your application in a Docker container, you first need to build an image of your application. This image encapsulates your application’s dependencies and configurations and is used to start a container to run the application.
• Building a Docker image requires creating a Dockerfile that specifies the instructions needed to build the image. This file defines the environment needed to run your application, such as the base image, dependencies, and any additional configurations. Once you have your Dockerfile, you can use Docker commands to build the image, tag it with a name, and then push it to a registry for later use.
• Docker to be an excellent tool for containerizing applications due to its portability, scalability, and reliability. With Docker, you can easily deploy your application to any environment that supports Docker, such as Kubernetes or Amazon ECS. Docker also provides versioning features that enable you to track changes made to your application’s image over time.

FROM openjdk:17-alpine
ARG JAR_FILE
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java","-jar","/app.jar"]

Kubernetes Cluster for Container Orchestration

• The power of containerization to build and deploy complex applications made up of many Docker containers, combined into microservices. To manage these containers at scale, I turn to Kubernetes, a powerful container orchestration tool that offers features such as high availability, scalability, and automated container deployment, scaling, and management.
• To get started with Kubernetes, you’ll need access to a Kubernetes cluster. A cluster consists of a master node (or cloud Kubernetes service) and one or more worker nodes. The master node takes on the administrative work of the cluster and provides the core functionality of Kubernetes.

CI/CD Pipeline using Github Actions

• To Implement a CI/CD pipeline to achieve continuous software delivery and customer satisfaction.I leveraged Github Actions to create a deployment pipeline that triggers on every commit to the master branch. This allows the development team to focus on writing code, while the pipeline takes care of the deployment process.
• To get started, logged into Azure account using the App Registration Credentials.
• Next, utilized the Azure Container Registry Build Command to build the Docker image using the Dockerfile and push it to the Azure Container Registry.
• In order to ensure secure connections to the MySQL database, create Kubernetes Secrets containing the database connection string, username, and password inside the cluster.
• These secrets were stored in a secure location within Github Actions, which allowed me to reference them during the deployment process.
• After the secrets were created, deploy the rest of the Kubernetes configurations. Instead of using the Azure AKS Deploy Action, use the Azure AKS Set Context Action.
• This provided ability to replace certain strings inside my configuration files, such as injecting the Docker image’s name inside the deployment configuration file. Since the image tag changes with every commit, this dynamic approach ensures that the correct image is deployed.
• Finally, if the deployment process completed without any errors, the updated version of the application would be running in the Azure Kubernetes cluster.

Conclusion

• Deploying a Spring Boot application to an Azure Kubernetes cluster using Github Actions is an efficient and streamlined process that can greatly benefit software development teams.
• By containerizing the application using Docker and utilizing Kubernetes for container orchestration, developers can easily manage and scale their applications with high availability and reliability.
• Github Actions provides a powerful automation tool for the deployment process, allowing teams to focus on writing code while the pipeline takes care of the deployment process. With the help of Azure Container Registry and Kubernetes Secrets, the deployment process can also be secured and streamlined.