zkt26/sk1/README.md

Smart Share Hub – Secure Cloud File & Note Sharing Platform

Overview

Smart Share Hub is a cloud-based web application deployed using Docker containers on a Linux virtual machine. The application allows users to:

• Upload and share files
• Create and share notes
• Access the application publicly through a web browser
• Use HTTPS encryption
• Store persistent data using PostgreSQL and Docker volumes

Developed for the Cloud Technologies assignment.

---

Features

File Upload System

• Upload files through the web interface
• Files stored persistently inside a Docker volume
• Accessible through the browser

Shared Notes

• Users can create notes
• Notes are stored in a PostgreSQL database
• Notes can be viewed publicly

HTTPS Support

• Application accessible through HTTPS
• SSL/TLS certificate configured
• Secure encrypted communication

Docker-Based Deployment

• Fully containerized application
• Easy deployment using Docker Compose
• Repeatable deployment using scripts

Automatic Restart

• Containers restart automatically after failure
• Uses Docker restart policies

Backup Support

• Backup script included
• Application data can be archived easily

Persistent Storage

• PostgreSQL database volume
• Upload storage volume

Environment Variable Configuration

• Database secrets stored in .env
• Sensitive data excluded from Git repository

Logging

• NGINX access logs available
• Backend logs accessible through Docker

---

Technologies Used

Layer	Technology
Backend	Python, Flask, psycopg2
Database	PostgreSQL 15
Frontend	HTML, CSS, JavaScript
Reverse Proxy	NGINX
Containerization	Docker, Docker Compose

---

System Architecture

The application consists of four containers:

Container	Purpose
frontend	Serves frontend web files
backend	Flask API server
postgres	PostgreSQL database
nginx	Reverse proxy and HTTPS

---

Environment Variables

Secrets are stored using environment variables. Create a .env file in the project root:

DB_PASSWORD=xxxxxxxx

The .env file is excluded from Git using .gitignore.

---

Docker Compose

The main deployment file is docker-compose.yml.

# Start application
docker-compose up -d --build

# Stop application
docker-compose down

# Remove everything including volumes
docker-compose down -v

Database configuration example:

environment:
  POSTGRES_DB: smartshare
  POSTGRES_USER: postgres
  POSTGRES_PASSWORD: ${DB_PASSWORD}

---

Deployment Instructions

1. Install Docker

sudo apt update
sudo apt install docker.io docker-compose -y

2. Clone Repository

git clone <repository-url>
cd sk1

3. Create Environment File

nano .env

Add the following:

DB_PASSWORD=xxxxxxxx

4. Start Application

docker-compose up -d --build

---

Public Access

The application is publicly accessible at:

https://your-domain

Example:

https://joblin-share.duckdns.org

---

HTTPS Configuration

HTTPS is configured using:

• NGINX reverse proxy
• SSL/TLS certificates

All traffic is redirected through the secure HTTPS protocol.

---

Persistent Storage

Volume	Purpose
postgres_data	PostgreSQL database storage
uploads	Uploaded files

Data remains intact after container restarts.

---

Automatic Restart Policy

All containers are configured with:

restart: always

This ensures automatic recovery after crashes or server reboots.

---

NGINX Reverse Proxy

NGINX handles:

• HTTPS termination
• Reverse proxy routing
• Static frontend delivery
• API request forwarding

Route	Target
/	Frontend
/api/	Backend API

---

Security Features

• HTTPS encryption
• Environment-based secret management
• Docker network isolation
• Reverse proxy protection

---

Backup System

Run the backup script:

./backup.sh

The script:

• Creates compressed backups
• Stores them inside /backups
• Can be used for recovery

Example backup file:

backup_2026-05-12.tar.gz

---

Scripts

Script	Description	Usage
prepare-app.sh	Starts the application automatically	./prepare-app.sh
remove-app.sh	Stops and removes all containers	./remove-app.sh
backup.sh	Creates a compressed application backup	./backup.sh

---

Logs

# NGINX access logs
docker logs nginx

# Backend application logs
docker logs backend

# PostgreSQL logs
docker logs postgres