TCP Chat Server

A full-stack real-time chat application built using:

• Python
• FastAPI
• React
• WebSockets
• PostgreSQL
• bcrypt Authentication

This project evolved phase-by-phase from a basic TCP socket server into a modern real-time chat system with authentication, persistent chat history, online user tracking, and responsive frontend support.

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Features

Authentication

• User Registration
• User Login
• Password Hashing with bcrypt
• Duplicate Login Prevention
• PostgreSQL-backed User Storage

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Real-Time Communication

• Multi-client real-time messaging
• WebSocket-based communication
• Instant message synchronization
• Online users tracking
• Join/Leave system messages

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Persistence

• PostgreSQL database integration
• Persistent chat history
• Automatic history recovery on reconnect

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Frontend

• React + Vite frontend
• Responsive UI
• Mobile-friendly layout
• Inline authentication messages
• Real-time updates without refresh

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Tech Stack

Backend

• Python
• FastAPI
• WebSockets
• psycopg2
• bcrypt

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Frontend

• React
• Vite

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Database

• PostgreSQL

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Project Structure

tcp-chat-server/
│
├── client/
├── frontend/
├── server/
├── shared/
├── websocket_server/
│
├── requirements.txt
└── README.md

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Installation

Clone Repository

git clone https://github.com/karthikeya20012007/tcp-chat-server.git

cd tcp-chat-server

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Backend Setup

Create Virtual Environment

python -m venv venv

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Activate Virtual Environment

Linux / WSL

source venv/bin/activate

Windows

venv\Scripts\activate

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Install Dependencies

pip install fastapi uvicorn psycopg2 bcrypt python-multipart

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PostgreSQL Setup

Create Database

CREATE DATABASE tcp_chat;

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Create Users Table

CREATE TABLE users (
    id SERIAL PRIMARY KEY,
    username VARCHAR(50) UNIQUE NOT NULL,
    password_hash TEXT NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

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Create Messages Table

CREATE TABLE messages (
    id SERIAL PRIMARY KEY,
    sender VARCHAR(50),
    content TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

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Configuration

Update database credentials inside:

shared/config.py

Example:

DB_HOST = "localhost"
DB_NAME = "tcp_chat"
DB_USER = "postgres"
DB_PASSWORD = "your_password"

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Running Backend

uvicorn websocket_server.app:app --reload --host 0.0.0.0 --port 8000

Backend runs on:

http://localhost:8000

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Frontend Setup

cd frontend

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Install Packages

npm install

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Start Frontend

npm run dev -- --host

Frontend runs on:

http://localhost:5173

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Usage

Register

Create a new account using:

• Username
• Password

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Login

Login using registered credentials.

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Chat

• Send real-time messages
• View online users
• Receive chat history automatically
• Join from multiple devices on the same network

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Future Improvements

• JWT Authentication
• Private Chats
• Chat Rooms
• Redis Pub/Sub Scaling
• Docker Deployment
• Message Timestamps
• Typing Indicators
• Media/File Sharing
• Kubernetes Deployment
• End-to-End Encryption

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Learning Outcomes

This project demonstrates:

• Socket Programming
• Concurrent Systems
• WebSocket Architecture
• Full-Stack Integration
• Real-Time Systems
• Authentication Systems
• PostgreSQL Persistence
• Frontend/Backend Communication
• Responsive UI Design

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Author

Karthikeya

GitHub: https://github.com/karthikeya20012007