82 lines
2.8 KiB
Markdown
82 lines
2.8 KiB
Markdown
# PI Visualization Web Application on Kubernetes
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## Overview
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This project deploys a Python web application using Flask on a Kubernetes cluster. The application displays the first 300 digits of PI with an interactive visualization. The deployment includes a Namespace, Deployment, StatefulSet (with PersistentVolume and PersistentVolumeClaim), and Service.
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## Application Description
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- The web application visualizes PI digits at the root URL (`/`).
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- Each digit appears one at a time (every 0.5 seconds by default) with a unique color.
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- Users can control the animation (start, pause, reset) and adjust the speed.
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- The application uses one container image built from the Dockerfile provided.
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## Containers
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- **simple-web-app**: Runs the Python Flask application on port 5000.
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## Kubernetes Objects
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- **Namespace**: Isolates all the resources under `my-app`.
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- **Deployment**: Manages the stateless web application pods with 2 replicas for high availability.
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- **StatefulSet**: Manages stateful application pods that require persistent storage.
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- **PersistentVolume (PV)**: Provides persistent storage from the host (1GB).
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- **PersistentVolumeClaim (PVC)**: Claims the PV for storage.
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- **Service**: Exposes the web application externally via NodePort 30007.
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## Networking and Storage
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- The application uses Kubernetes networking to enable communication between pods.
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- The StatefulSet uses a volume claim template that binds to a PersistentVolume mounted at `/data`.
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## Container Configuration
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- The container is based on Python and includes Flask.
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- It exposes port 5000 to serve the web application.
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- Resource limits and readiness probes are configured for better stability.
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## How to Prepare, Run, Pause, and Delete the Application
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1. **Prepare the application:**
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```bash
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./prepare-app.sh
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```
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This script builds the Docker image and creates the directory for persistent volume.
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2. **Start the application:**
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```bash
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./start-app.sh
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```
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This script creates all necessary Kubernetes objects in the correct order.
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3. **Pause or delete the application:**
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```bash
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./stop-app.sh
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```
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This script removes all Kubernetes objects created by `start-app.sh`.
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## Accessing the Application
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To access the application:
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1. Find the IP address of your Kubernetes node:
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```bash
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kubectl get nodes -o wide
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```
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2. Access the application in your browser at:
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```
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http://<NODE_IP>:30007
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```
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Where `<NODE_IP>` is the IP address of any of your Kubernetes nodes.
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## Troubleshooting
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If you encounter issues:
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1. Check pod status:
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```bash
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kubectl get pods -n my-app
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```
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2. View pod logs:
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```bash
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kubectl logs <pod-name> -n my-app
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```
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3. Check service status:
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```bash
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kubectl get svc -n my-app
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``` |