zkt25/sk1

Calculator Web Application on Azure Kubernetes Service (AKS)

---

##Application Description This project is a simple web-based calculator that performs basic mathematical operations. It allows users to calculate expressions and save the results. A "Show History" button displays previously saved calculations.

Built with:

• Frontend: HTML/CSS/JavaScript served via Nginx

• Backend: Flask (Python) application connected to a PostgreSQL database

• Database: PostgreSQL 15

---

##Public Cloud Environment

• Provider: Microsoft Azure

• Service Used: Azure Kubernetes Service (AKS)

• Certificate Issuer: cert-manager with Let's Encrypt

• Domain: https://aliscloudwork.tech

---

##Kubernetes and Cloud Components

• Deployments:

  • Frontend Deployment (Nginx server)
  • Backend Deployment (Flask server)
  • PostgreSQL Deployment (Database server)

• Services:

  • Frontend Service (ClusterIP)
  • Backend Service (ClusterIP)
  • PostgreSQL Service (ClusterIP)
  • Ingress Controller Service (LoadBalancer)

• Ingress:

  • Ingress resource used to route traffic and enable HTTPS

• Persistent Volume:

  • PostgreSQL database uses a Persistent Volume Claim (PVC) for data persistence

• Certificate Management:

  • cert-manager with Let's Encrypt to generate HTTPS certificates automatically

---

##Files Included

• prepare-app.sh: Script to deploy all Kubernetes objects and services automatically

• remove-app.sh: Script to delete all Kubernetes objects and services

• kubi/*.yaml: Kubernetes deployment, service, ingress, PVC configuration files

• backend/Dockerfile: Dockerfile for the Flask backend application

• frontend/Dockerfile: Dockerfile for the Nginx frontend application

• frontend/default.conf: Nginx configuration file for routing

• README.md: This documentation file

---

##How to View and Use the Application Open a web browser and visit: https://aliscloudwork.tech

Use the calculator to perform operations.

Click the "Show History" button to view saved calculations.

---

##Running Scripts

• To deploy the application:
  • bash prepare-app.sh
• To delete the application:
  • bash remove-app.sh

---

##External Sources and Tools Used

• DockerHub for container images

• Let's Encrypt for SSL certificates

• cert-manager for Kubernetes certificate automation

• Azure CLI for AKS management

• Official documentation for Nginx, Flask, Kubernetes YAML syntax

---

##Final Notes

• HTTPS is fully functional.

• Kubernetes ensures all components are modular and recover automatically.

• Database uses persistent storage for calculation history.