Blockchain

A simple blockchain implemented from scratch in Rust inspired by Bitcoin. This project is a learning exercise to understand the basic concepts of blockchain technology, including blocks, transactions, and consensus mechanisms.

Features

I go in depth about these features in this Medium article.

• Proof of Work (PoW)
• Peer to peer communication
• Peer discovery
• Fork detection and resolution
• Block creation and validation
• Transaction validation
• Mempool implementation
• Postgres database
• Kubernetes & Helm deployment
• Client wallet GUI

Requirements

• Rust (latest stable)
• Cargo
• PostgreSQL
• Optional: Docker, Kubernetes & Helm for dockerized deployment

Usage

1. Clone the repository

git clone https://github.com/connormck333/blockchain.git
cd blockchain

2. Set up the database

• Ensure PostgreSQL is running and accessible.
• Create a .env file and add the following variables:

POSTGRES_USERNAME=your_username
POSTGRES_PASSWORD=your_password
POSTGRES_HOST=localhost

3. Build the project

cd node
cargo build --release

4. Run the opening node

• Host: the address that the node will listen on. E.g: http://localhost
• Port: the port that the node will listen on. E.g: 8080
• External IP: the address that other nodes will use to connect to this node.
• External Port: the port that other nodes will use to connect to this node.

cargo run full open <host>:<port> <external_ip>:<external_port>

5. Run miner nodes

• Host: the address that the node will listen on. E.g: http://localhost
• Port: the port that the node will listen on. E.g: 8081
• Existing Node Host: the address of an existing node to join. E.g: http://127.0.0.1
• Existing Node Port: the port of an existing node to join. E.g: 8080
• External IP: the address that other nodes will use to connect to this node.
• External Port: the port that other nodes will use to connect to this node.

cargo run miner join <host>:<port> <existing_node_host>:<existing_node_port> <external_ip>:<external_port>

6. Build and run the wallet GUI

cd ../wallet
cargo build --release
cargo run --release

Alternative: Dockerized Deployment

If you prefer to run the blockchain in a Dockerized environment, you can use the provided Docker and Kubernetes configurations. I have provided a simple deployment script that uses Helm to deploy the blockchain nodes:

./deploy.sh

And to uninstall the deployment:

./stop.sh

Future Work

• Consider security requirements and implement necessary measures.
• Add more features like smart contracts, token standards, etc.
• Improve the wallet GUI with ability to view transactions and balances.
• Implement more advanced consensus mechanisms like Proof of Stake (PoS).