bitbank #

A comprehensive Dart API wrapper for Bitbank cryptocurrency exchange with built-in weighted average cost calculation functionality.

🚀 Features #

• Complete Bitbank API Integration: Seamlessly interact with Bitbank's private API
• Asset Management: Retrieve detailed information about your cryptocurrency holdings
• Trade History: Access comprehensive trading history with detailed transaction data
• Weighted Average Cost Calculation: Built-in functionality to calculate investment cost basis
• Type-Safe Models: Robust data structures using Freezed for immutable, serializable models
• HMAC-SHA256 Authentication: Secure API authentication implementation
• Network Information: Detailed network and withdrawal fee information for each asset

📦 Installation #

Add this to your package's pubspec.yaml file:

dependencies:
  bitbank: ^0.0.1

Then run:

dart pub get

🔧 Setup #

1. Obtain your API credentials from Bitbank
2. Create API key and secret in your Bitbank account settings
3. Ensure your API key has the necessary permissions for the endpoints you plan to use

📖 Usage #

Basic Setup #

import 'package:bitbank/bitbank.dart';

final bitbank = Bitbank(
  apiKey: 'your_api_key_here',
  apiSecret: 'your_api_secret_here',
);

Get Asset Information #

Retrieve detailed information about your cryptocurrency holdings:

try {
  final assetsResponse = await bitbank.assets();

  print('Success: ${assetsResponse.success}');
  print('Number of assets: ${assetsResponse.data.assets.length}');

  for (final asset in assetsResponse.data.assets) {
    print('Asset: ${asset.asset}');
    print('Free Amount: ${asset.freeAmount}');
    print('Onhand Amount: ${asset.onhandAmount}');
    print('Locked Amount: ${asset.lockedAmount}');
    print('Withdrawal Fee: ${asset.withdrawalFee}');
    print('---');
  }
} catch (e) {
  print('Error: $e');
}

Get Trade History #

Access your trading history for specific currency pairs:

try {
  final tradeHistory = await bitbank.tradeHistory(pair: 'btc_jpy');

  print('Number of trades: ${tradeHistory.data.trades.length}');

  for (final trade in tradeHistory.data.trades) {
    print('Trade ID: ${trade.tradeId}');
    print('Pair: ${trade.pair}');
    print('Side: ${trade.side}'); // 'buy' or 'sell'
    print('Amount: ${trade.amount}');
    print('Price: ${trade.price}');
    print('Fee: ${trade.feeAmountBase}');
    print('Executed At: ${DateTime.fromMillisecondsSinceEpoch(trade.executedAt)}');
    print('---');
  }
} catch (e) {
  print('Error: $e');
}

Calculate Weighted Average Cost #

Automatically calculate the weighted average cost of your investments:

try {
  final tradeHistory = await bitbank.tradeHistory(pair: 'btc_jpy');

  // Calculate weighted average cost from trade history
  final result = tradeHistory.calculateWeightedAverageCost();

  print('Current Quantity: ${result.currentQuantity}');
  print('Average Cost: ${result.averageCost}');
  print('Total Cost: ${result.totalCost}');
} catch (e) {
  print('Error: $e');
}

Manual Weighted Average Cost Calculation #

You can also calculate weighted average cost manually with custom transaction data:

import 'package:bitbank/bitbank.dart';

// Create transaction list manually
final transactions = [
  Transaction(quantity: 1.0, price: 5000000), // Buy 1 BTC at 5,000,000 JPY
  Transaction(quantity: 0.5, price: 6000000), // Buy 0.5 BTC at 6,000,000 JPY
  Transaction(quantity: -0.3, price: 7000000), // Sell 0.3 BTC at 7,000,000 JPY
];

final result = calWeightedAverageCost(transactions);

print('Current Holdings: ${result.currentQuantity} BTC');
print('Average Cost: ${result.averageCost} JPY per BTC');
print('Total Investment: ${result.totalCost} JPY');

📊 Data Models #

This library provides comprehensive, type-safe data models:

Asset #

• Asset information including balances, fees, and network details
• Free, onhand, locked, and withdrawing amounts
• Withdrawal fees and deposit/withdrawal status
• Network-specific information for multi-chain assets

Trade #

• Complete trade information including IDs, amounts, and fees
• Execution timestamps and maker/taker information
• Automatic conversion to Transaction objects for cost calculation

WeightedAverageCostResult #

• Current quantity holdings
• Calculated average cost per unit
• Total cost basis of current holdings

🔒 Security #

• All API requests are authenticated using HMAC-SHA256 signatures
• API credentials are never logged or exposed
• Secure nonce generation for request authentication

🤝 Contributing #

Contributions are welcome! Please feel free to submit a Pull Request. For major changes, please open an issue first to discuss what you would like to change.

📄 License #

This project is licensed under the MIT License - see the LICENSE file for details.

🆘 Support #

If you find this package helpful, please consider:

• ⭐ Starring the repository
• 🐛 Reporting bugs via GitHub Issues
• 💡 Suggesting new features
• 💖 Sponsoring the project

🔗 Links #

• Bitbank Official Website
• Bitbank API Documentation
• Package on pub.dev