Enhance README with detailed project information

Expanded README with architecture, features, deployment strategy, monitoring, and setup instructions.

Author: vimal-java-dev

README.md

@@ -1,9 +1,183 @@
+# 🚀 Contact API — Production-Ready Spring Boot Backend
+
+A **production-grade backend system** built with Spring Boot, containerised using Docker, and deployed on a VPS with **zero-downtime blue-green deployment**, **NGINX reverse proxy**, and **full monitoring using Prometheus & Grafana**.
+
+---
+
 ## 🏗️ Architecture Overview
 
-![Minimal Architecture](assets/architecture-minimal.png)
+<p align="center">
+  <img src="assets/architecture-minimal.png" width="700"/>
+</p>
+
+---
+
+## ⚙️ Detailed System Architecture
+
+<p align="center">
+  <img src="assets/architecture-detailed.png" width="900"/>
+</p>
+
+---
+
+## 🚀 Key Features
+
+* 🔁 **Blue-Green Deployment** (Zero Downtime)
+* 🐳 **Dockerized Application**
+* 🌐 **NGINX Reverse Proxy Routing**
+* 📊 **Monitoring with Prometheus & Grafana**
+* 🛢️ **PostgreSQL Database Integration**
+* ⚙️ **CI/CD via GitHub + GHCR**
+* 🔐 **Environment-based Configuration (.env)**
+* 📈 **Production Observability Setup**
+
+---
+
+## 🧱 Tech Stack
+
+| Layer      | Technology           |
+| ---------- | -------------------- |
+| Backend    | Spring Boot          |
+| Database   | PostgreSQL           |
+| Container  | Docker               |
+| Proxy      | NGINX                |
+| Monitoring | Prometheus, Grafana  |
+| CI/CD      | GitHub Actions, GHCR |
+| Deployment | VPS (Linux)          |
+
+---
+
+## 🔁 Deployment Strategy (Blue-Green)
+
+This project implements a **blue-green deployment strategy** to ensure zero downtime.
+
+### Flow:
+
+1. New version is deployed to **inactive environment** (Green)
+2. Health checks are verified
+3. NGINX switches traffic:
+
+   ```
+   Blue → Green
+   ```
+4. Old version remains as a fallback
+
+### Result:
+
+* ✅ Zero downtime
+* ✅ Instant rollback capability
+* ✅ Safe production deployments
+
+---
+
+## 📊 Monitoring & Observability
+
+* **Prometheus** scrapes metrics from:
+
+  ```
+  /actuator/prometheus
+  ```
+* **Grafana** visualizes:
+
+  * CPU usage
+  * Memory usage
+  * Request metrics
+  * Container health
+
+---
+
+## 🐳 Docker Setup
+
+### Run with Docker Compose
+
+```bash
+docker-compose up -d
+```
+
+### Services:
+
+* contact-api (blue/green)
+* postgres
+* prometheus
+* grafana
+* nginx
+
+---
+
+## 🌐 API Endpoints
+
+| Method | Endpoint       | Description       |
+| ------ | -------------- | ----------------- |
+| GET    | /contacts      | Get all contacts  |
+| POST   | /contacts      | Create contact    |
+| GET    | /contacts/{id} | Get contact by ID |
+| PUT    | /contacts/{id} | Update contact    |
+| DELETE | /contacts/{id} | Delete contact    |
+
+---
+
+## 🧪 Run Locally
+
+```bash
+git clone https://github.com/vimal-java-dev/vimaltech-contact-api
+cd vimaltech-contact-api
+
+docker-compose up --build
+```
+
+---
+
+## ☁️ Production Deployment
+
+### Steps:
+
+1. Push Docker image to GHCR
+2. Pull the image on the VPS
+3. Run `deploy.sh`
+4. Switch NGINX between blue/green
+
+---
+
+## 🔐 Security Considerations
+
+* Environment variables via `.env`
+* NGINX as reverse proxy (no direct exposure)
+* Container isolation
+* Controlled port exposure
+
+---
+
+## 📸 Screenshots (Add Here)
+
+> Add:
+
+* Grafana dashboard
+* Prometheus targets
+* Docker containers
+* Blue-Green switch logs
+
+---
+
+## 🎯 What This Project Demonstrates
+
+* Real-world backend system design
+* DevOps integration with backend development
+* Zero-downtime deployment strategy
+* Monitoring & observability setup
+* Production-ready architecture thinking
 
 ---
 
-## ⚙️ Detailed Architecture
+## 🌍 Live Demo
+
+👉 https://vimaltech.dev/
+
+---
 
-![Detailed Architecture](assets/architecture-detailed.png)
+## 👨‍💻 Author
+
+**Vimal Patel**
+
+Backend Developer | Spring Boot | DevOps Enthusiast
+
+---