S256 Block Explorer

A modern, high-performance block explorer for the S256 (SHA256 Coin) blockchain with MongoDB backend.

Block Explorer for SHA256coin (S256)
Built with Node.js and Express

Website • Explorer

Features

• Real-time blockchain statistics
• Fast MongoDB-backed database
• Browse recent blocks with pagination
• View detailed block information
• View transaction details
• Search by block height, block hash, transaction ID, or address
• Address balance tracking
• Network statistics history
• Auto-syncing with blockchain
• Responsive design matching S256 website theme

Architecture

• Frontend: Modern HTML/CSS/JS interface
• API: Express.js REST API
• Database: MongoDB for fast queries
• Sync Service: Background process that syncs blocks from S256 daemon

Prerequisites

• Node.js (v16 or higher)
• MongoDB (v6 or higher)
• npm or yarn
• Running S256 daemon with RPC enabled

S256 Daemon Configuration

Before running the explorer, make sure your S256 daemon is configured for RPC access.

1. Create or edit ~/.sha256coin/sha256coin.conf (or your custom data directory):

# RPC Configuration
server=1
txindex=1
rpcuser=your_rpc_username
rpcpassword=your_secure_rpc_password
rpcport=25332
rpcallowip=127.0.0.1

# Optional: Enable transaction indexing for full explorer functionality
txindex=1

2. If you add txindex=1 to an existing node, you'll need to reindex:

./bitcoind -reindex

Installation

1. Install MongoDB

Ubuntu/Debian:

# Import MongoDB public key
curl -fsSL https://www.mongodb.org/static/pgp/server-7.0.asc | sudo gpg -o /usr/share/keyrings/mongodb-server-7.0.gpg --dearmor

# Add repository (Ubuntu 22.04 - for other versions see MongoDB docs)
echo "deb [ signed-by=/usr/share/keyrings/mongodb-server-7.0.gpg ] https://repo.mongodb.org/apt/ubuntu jammy/mongodb-org/7.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-7.0.list

# Install MongoDB
sudo apt-get update
sudo apt-get install -y mongodb-org

# Start and enable service
sudo systemctl start mongod
sudo systemctl enable mongod

macOS:

brew tap mongodb/brew
brew install mongodb-community
brew services start mongodb-community

Or use MongoDB Atlas (free cloud MongoDB): https://www.mongodb.com/cloud/atlas

2. Install Node.js dependencies

cd explorer
npm install

3. Configure the explorer

Create .env file:

cp .env.example .env

Edit .env with your configuration:

# S256 RPC
RPC_USER=your_rpc_username
RPC_PASSWORD=your_secure_rpc_password
RPC_HOST=127.0.0.1
RPC_PORT=25332

# MongoDB
MONGODB_URI=mongodb://localhost:27017/s256explorer

# Server
PORT=3000

Running the Explorer

The explorer consists of two services that need to run simultaneously:

Option 1: Manual (Development)

Terminal 1 - Start the sync service:

npm run sync

Terminal 2 - Start the API server:

npm start

The explorer will be available at: http://localhost:3000

Option 2: PM2 (Production)

Using PM2 process manager (recommended for production):

# Install PM2 globally
npm install -g pm2

# Start both services
npm run pm2:start

# View logs
pm2 logs

# Stop services
npm run pm2:stop

# Restart services
npm run pm2:restart

Option 3: Simple Version (No MongoDB)

If you don't want to use MongoDB, you can run the simple version:

npm run start:simple

This version queries RPC directly (slower, not recommended for production).

Usage

1. View Blockchain Stats: The top section shows real-time blockchain information
2. Recent Blocks: Scroll down to see the latest 20 blocks
3. Search: Use the search bar to find blocks (by height or hash) or transactions (by txid)
4. Block Details: Click any block to view detailed information
5. Transaction Details: Click any transaction to view inputs and outputs

API Endpoints

The explorer provides a REST API:

• GET /api/blockchain-info - Get blockchain statistics
• GET /api/blocks/recent/:count - Get recent blocks (default: 10)
• GET /api/block/:hashOrHeight - Get block by hash or height
• GET /api/tx/:txid - Get transaction by ID
• GET /api/search/:query - Search for block or transaction
• GET /api/mempool - Get mempool information

Troubleshooting

Connection Refused

If you get "Connection refused" errors:

1. Make sure the S256 daemon is running:

   ./bitcoin/build/bin/bitcoin-cli getblockchaininfo

2. Check RPC credentials match between s256.conf and .env

3. Verify RPC port (default: 25332)

Missing Transactions

If transactions don't show up:

1. Enable txindex=1 in sha256coin.conf
2. Restart daemon with -reindex flag

Port Already in Use

If port 3000 is already in use, change the PORT in .env:

PORT=3001

Deployment

For production deployment:

1. Use a process manager like PM2:

   npm install -g pm2
   pm2 start server.js --name s256-explorer
   pm2 save
   pm2 startup

2. Set up nginx reverse proxy for HTTPS

3. Configure firewall to allow traffic on the explorer port

License

MIT License - See LICENSE file for details

Support

For issues and questions, please open an issue on the project GitHub repository.