Flask Hello World Application

This project demonstrates how to deploy a simple Flask "Hello World" application on Kubernetes. It includes the necessary Kubernetes manifests for deployment, service, Ingress class, and Ingress resource.

Prerequisites

• Kubernetes cluster (e.g., Minikube, kind, or a managed Kubernetes service)
• kubectl CLI tool
• Docker (to build and push the image)

Project Structure

• Dockerfile: Dockerfile for building the Flask application image
• deployment.yaml: Kubernetes Deployment resource
• service.yaml: Kubernetes Service resource
• ingress-class.yaml: IngressClass resource (for NGINX Ingress controller)
• ingress.yaml: Ingress resource to route traffic

Build and Push Docker Image

1. Build the Docker Image:

   docker build -t your-dockerhub-username/hello-world-app:latest .
   docker push your-dockerhub-username/hello-world-app:latest

   Replace "hello-world-app" with your repository name on Docker Hub.

   This step is not needed to run the example project as it already uses an image from public Docker Hub repository.

Using the application

1. Applying Kubernetes Manifests

   Use make start command to apply Kubernetes manifests. This command will apply related Kubernetes files using command kubectl apply -f <resource-file-name>. You can see Makefile for commands.

   Warning: If you get an error during creation of Kubernetes resources please run make start command again. This should be fixed soon.

2. Accessing the application

   Use your browser or any API tool to send a GET request to your application. Application uses http://localhost/hello-world-app as default. You should see Hello World! as response.

3. Stopping the application

   Use make stop to delete all running Kubernetes resources related to application.