DocLab – Dockerized Full-Stack Message Board

DocLab is a full-stack web application built using React, Node.js, PostgreSQL, and Docker.
The application allows users to post messages, stores them persistently in a relational database, and displays them in real time through a modern web interface.

This project demonstrates real-world full-stack architecture, database relationships, and containerized deployment.

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🚀 Features

• User-based messaging system
• Each message is associated with a user
• React frontend with dynamic UI updates
• Node.js + Express REST API
• PostgreSQL relational database
• SQL joins for fetching user-message data
• Docker & Docker Compose for containerization
• Persistent database storage using Docker volumes
• Nginx for serving frontend and proxying API requests and make it understandable

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🛠️ Tech Stack

Frontend

• React (Create React App)
• CSS
• Nginx (production server)

Backend

• Node.js
• Express.js
• PostgreSQL (pg library)

DevOps

• Docker
• Docker Compose

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📂 Project Structure

doclab/ ├── frontend/ │ ├── src/ │ │ ├── App.js │ │ ├── App.css │ │ └── index.js │ ├── Dockerfile │ └── nginx.conf ├── backend/ │ ├── server.js │ ├── db.js │ ├── init.sql │ └── Dockerfile ├── docker-compose.yml └── README.md

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🧠 System Architecture

Browser ↓ React Frontend (Nginx) ↓ /api Node.js Backend (Express) ↓ PostgreSQL Database

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🧩 Database Design

Users Table

• Stores user information
• Each user can send multiple messages

Messages Table

• Stores message content and timestamp
• References users using foreign key

Relationship:
One-to-Many (User → Messages)

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⚙️ Prerequisites

• Docker
• Docker Desktop
• Git

No need to install Node.js or PostgreSQL locally.

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▶️ How to Run the Project Locally

1️⃣ Clone the repository

git clone https://github.com/kumar1035/doclab.git
cd doclab

2️⃣ Start the application
docker compose up --build
3️⃣ Access the application
Frontend:

http://localhost:3000
Backend API:

http://localhost:5000/api/messages

🗄️ Database Verification (PostgreSQL)

To view stored users and messages:

docker exec -it postgres psql -U postgres -d doclab
\dt
SELECT * FROM users;
SELECT * FROM messages;
\q(to exit)
🐳 Docker Implementation Details

Each service (frontend, backend, database) runs in a separate container

Docker Compose manages service orchestration

PostgreSQL data is persisted using Docker volumes

Backend communicates with database via Docker internal network

Nginx proxies API requests from frontend to backend