KrakenBridge

A comprehensive Ruby gem for seamless integration with Kraken cryptocurrency exchange APIs. Supports both REST and WebSocket protocols for public market data and authenticated trading operations.

Features

✅ Complete REST API Support: Public and private endpoints
✅ WebSocket Real-time Feeds: Ticker, trades, OHLC/Klines, and spread data
✅ Automatic Nonce Generation: Millisecond-precision timestamps
✅ Signature Generation: HMAC-SHA512 authentication per Kraken specs
✅ Rate Limiting: Built-in request rate limiting
✅ Automatic Retries: Configurable retry logic with exponential backoff
✅ Error Handling: Comprehensive error classes and logging
✅ 2FA Support: Optional OTP parameter for two-factor-authenticated accounts

Installation

Add this line to your application's Gemfile:

gem 'kraken_bridge'

Then execute:

bundle install

Or install it yourself:

gem install kraken_bridge

Quick Start

Basic Usage - Public API

require 'kraken_bridge'

client = KrakenBridge::Client.new

# Get server time
time = client.market_data.time
puts time.data

# Get ticker data
ticker = client.market_data.ticker(['XBTUSD', 'ETHUSD'])
puts ticker.data

# Get OHLC data
ohlc = client.market_data.ohlc('XBTUSD', interval: 1)
puts ohlc.data

Authenticated Requests - Private API

require 'kraken_bridge'

client = KrakenBridge::Client.new(
  api_key: ENV['KRAKEN_API_KEY'],
  api_secret: ENV['KRAKEN_API_SECRET']
)

# Get account balance
balance = client.account.balance
puts balance.data

# Place a buy order
order = client.trading.add_order(
  pair: 'XBTUSD',
  type: 'buy',
  ordertype: 'limit',
  volume: 0.01,
  price: 25000
)
puts order.data

WebSocket - Real-time Data

require 'kraken_bridge'

client = KrakenBridge::Client.new

# Connect to WebSocket
client.connect_websocket do |message|
  puts "Raw message: #{message.inspect}"
end

# Subscribe to ticker
client.subscribe_ticker(['XBTUSD']) do |data|
  puts "Ticker: #{data}"
end

# Subscribe to trades
client.subscribe_trades(['XBTUSD']) do |data|
  puts "Trade: #{data}"
end

# Subscribe to OHLC/Klines
client.subscribe_ohlc(['XBTUSD'], interval: 1) do |data|
  puts "OHLC: #{data}"
end

# Let it run for 30 seconds
sleep(30)

# Disconnect
client.disconnect_websocket

Configuration

Environment Variables

export KRAKEN_API_KEY="your_public_api_key"
export KRAKEN_API_SECRET="your_base64_encoded_private_key"
export KRAKEN_API_URL="https://api.kraken.com"              # Optional
export KRAKEN_WEBSOCKET_URL="wss://ws.kraken.com"           # Optional

Programmatic Configuration

client = KrakenBridge::Client.new(
  api_key: 'your_api_key',
  api_secret: 'your_api_secret',
  timeout: 60,
  open_timeout: 10,
  rate_limit_enabled: true,
  retry_enabled: true,
  max_retries: 3,
  log_level: Logger::DEBUG
)

API Reference

Market Data (Public)

client.market_data.time
client.market_data.system_status
client.market_data.assets(assets: ['BTC', 'ETH'])
client.market_data.asset_pairs(pairs: ['XBTUSD', 'ETHUSD'])
client.market_data.ticker(['XBTUSD', 'ETHUSD'])
client.market_data.ohlc('XBTUSD', interval: 1)
client.market_data.order_book('XBTUSD')
client.market_data.trades('XBTUSD')
client.market_data.spread('XBTUSD')

Account (Private)

client.account.balance
client.account.extended_balance
client.account.trade_balance
client.account.open_orders
client.account.closed_orders
client.account.query_orders(txid: 'order_id')
client.account.trades_history
client.account.query_trades(txid: 'trade_id')
client.account.open_positions
client.account.ledger
client.account.query_ledger(id: 'entry_id')
client.account.trade_volume
client.account.request_export_report(description: 'Report', report: 'trades')
client.account.get_export_report(report: 'trades')

Trading (Private)

client.trading.add_order(pair: 'XBTUSD', type: 'buy', ordertype: 'limit', volume: 0.01, price: 25000)
client.trading.edit_order(txid: 'order_id', volume: 0.02, price: 26000)
client.trading.cancel_order('order_id')
client.trading.cancel_all_orders
client.trading.cancel_all_orders_after(timeout: 300)

WebSocket (Public Feeds)

client.connect_websocket { |msg| puts msg }
client.subscribe_ticker(['XBTUSD']) { |data| puts data }
client.subscribe_trades(['XBTUSD']) { |data| puts data }
client.subscribe_ohlc(['XBTUSD'], interval: 1) { |data| puts data }
client.subscribe_spread(['XBTUSD']) { |data| puts data }
client.disconnect_websocket

Error Handling

begin
  balance = client.account.balance
rescue KrakenBridge::Errors::AuthenticationError => e
  puts "Authentication failed: #{e.message}"
rescue KrakenBridge::Errors::RateLimitError => e
  puts "Rate limited: #{e.message}"
rescue KrakenBridge::Errors::ConnectionError => e
  puts "Connection failed: #{e.message}"
end

2FA (Two-Factor Authentication)

otp = '123456'
client.account.balance(otp: otp)
client.trading.add_order(pair: 'XBTUSD', type: 'buy', ordertype: 'limit', volume: 0.01, price: 25000, otp: otp)

Testing

bundle exec rspec

Security Recommendations

⚠️ Important:

Never commit API keys to version control
Use environment variables or secrets manager
Enable IP whitelisting on API keys
Use 2FA on your Kraken account
Rotate API keys regularly
Use read-only keys where possible

Troubleshooting

"EAPI:Invalid key"

Verify API key and secret are correct
Ensure API secret is base64 encoded
Check system clock is synchronized

"EAPI:Invalid nonce"

Sync system clock with NTP
Use separate API keys for different processes

Rate Limit Exceeded

Use WebSocket for real-time data
Increase time between requests
Enable automatic retries (enabled by default)

Contributing

Bug reports and pull requests are welcome on GitHub.

License

The gem is available as open source under the terms of the MIT License.

kraken_bridge

Development

Runtime