DemoBlockChain

A simple blockchain implementation built with Rust and Actix-web, demonstrating core blockchain concepts including block creation, proof-of-work mining, and a RESTful API interface.

📋 Table of Contents

• Overview
• Features
• Technology Stack
• Project Structure
• Prerequisites
• Installation
• Configuration
• Usage
• API Endpoints
• How It Works
• Development
• Contributing
• License

🔍 Overview

DemoBlockChain is an educational blockchain implementation that showcases the fundamental principles of blockchain technology. Built with Rust for performance and safety, it provides a REST API for interacting with the blockchain, allowing users to add transactions, mine blocks, and view the chain state.

✨ Features

• Block Creation: Create blocks with transaction data
• Proof of Work: Implements mining algorithm with adjustable difficulty
• SHA-256 Hashing: Cryptographic hashing for block integrity
• RESTful API: Easy-to-use HTTP endpoints for blockchain interaction
• CORS Support: Cross-origin resource sharing enabled
• Logging: Comprehensive logging for debugging and monitoring
• Transaction Management: Add and manage transactions before mining
• Chain Validation: Ensures blockchain integrity

🛠 Technology Stack

• Language: Rust (2024 edition)
• Web Framework: Actix-web 4.11.0
• Hashing: SHA-2 (sha2 crate)
• Serialization: Serde & Serde JSON
• CORS: Actix-cors 0.7.1
• Logging: env_logger 0.11.8 & log 0.4.28
• Time Management: Chrono 0.4.42
• Environment Variables: dotenv 0.15.0

📁 Project Structure

DemoBlockChain/
├── src/
│   └── main.rs          # Main application code
├── Cargo.toml           # Rust dependencies and project metadata
├── Cargo.lock           # Locked dependency versions
├── .env.example         # Example environment configuration
├── .gitignore          # Git ignore rules
└── README.md           # Project documentation

📋 Prerequisites

Before running this project, ensure you have the following installed:

• Rust: Version 1.70 or higher
  • Install from rustup.rs
• Cargo: Comes with Rust installation
• Git: For cloning the repository

🚀 Installation

1. Clone the repository

   git clone https://github.com/raunit-dev/DemoBlockChain.git
   cd DemoBlockChain

2. Install dependencies

   cargo build

3. Set up environment variables

   cp .env.example .env
   # Edit .env with your configuration

⚙️ Configuration

Create a .env file based on .env.example:

# Server configuration
RUST_LOG=info
PORT=8080

You can adjust the following settings:

• RUST_LOG: Logging level (trace, debug, info, warn, error)
• PORT: Server port (default: 8080)

💻 Usage

Running the Application

1. Development mode

   cargo run

2. Production build

   cargo build --release
   ./target/release/rust-back

3. With logging

   RUST_LOG=debug cargo run

The server will start on http://localhost:8080 (or your configured port).

🌐 API Endpoints

1. Get Blockchain

GET /blockchain

Returns the entire blockchain with all blocks.

Response:

{
  "chain": [...],
  "length": 3
}

2. Add Transaction

POST /transaction
Content-Type: application/json

Request Body:

{
  "sender": "Alice",
  "recipient": "Bob",
  "amount": 50
}

Response:

{
  "message": "Transaction added successfully"
}

3. Mine Block

POST /mine

Mines a new block with pending transactions.

Response:

{
  "message": "Block mined successfully",
  "block": {...}
}

4. Get Latest Block

GET /latest

Returns the most recent block in the chain.

5. Validate Chain

GET /validate

Checks if the blockchain is valid.

Response:

{
  "valid": true
}

🔧 How It Works

Block Structure

Each block contains:

• Index: Position in the blockchain
• Timestamp: When the block was created
• Transactions: List of transactions in the block
• Proof: Nonce value from proof-of-work
• Previous Hash: Hash of the previous block
• Hash: Current block's hash

Proof of Work

The mining algorithm:

1. Starts with a nonce of 0
2. Calculates hash of block data + nonce
3. Checks if hash meets difficulty requirement (leading zeros)
4. Increments nonce and repeats until valid hash found

Chain Validation

Validates the blockchain by:

1. Checking each block's hash is correct
2. Verifying each block's previous_hash matches the previous block
3. Ensuring proof-of-work is valid for each block

👨‍💻 Development

Running Tests

cargo test

Code Formatting

cargo fmt

Linting

cargo clippy

Watch Mode (with cargo-watch)

cargo install cargo-watch
cargo watch -x run

🤝 Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📝 License

This project is open source and available for educational purposes.

👤 Author

raunit-dev

• GitHub: @raunit-dev

🙏 Acknowledgments

• Built as a learning project to understand blockchain fundamentals
• Inspired by the original Bitcoin whitepaper
• Uses Rust for memory safety and performance

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