Connect to Sandbox - Buy Demo

gemini-sandbox.py

import json
import gemini


#you need sandbox public keys / private keys
#you can view your trades at https://exchange.sandbox.gemini.com/
public_key = ""  
private_key = ""
symbol = "BTCUSD"
tick_size = 8
#update symbol based on what crypto/fiat pair you want to buy. Default is BTCUSD, change to BTCEUR for Euros or ETHUSD for Ethereum (for example) - see all possibilities down in symbols and minimums link
#update tick size based on what crypto-pair you are buying. BTC is 8. Check out the API link below to see what you need for your pair
#https://docs.gemini.com/rest-api/#symbols-and-minimums

def _buyBitcoin(buy_size,pub_key, priv_key):
    # Set up a buy for 0.999 times the current price add more decimals for a higher price and faster fill, if the price is too close to spot your order won't post. 
    # Lower factor makes the order cheaper but fills quickly (0.5 would set an order for half the price and so your order could take months/years/never to fill)
    trader = gemini.PrivateClient(pub_key, priv_key, sandbox=True)
    symbol_spot_price = float(trader.get_ticker(symbol)['ask'])
    factor = 0.999
    #to set a limit order at a fixed price (ie. $55,525) set execution_price = "55525.00" or execution_price = str(55525.00)
    execution_price = str(round(symbol_spot_price*factor,2))

    #set amount to the most precise rounding (tick_size) and multiply by 0.998 for fee inclusion - if you make an order for $20.00 there should be $19.96 coin bought and $0.04 (0.20% fee)
    amount = round((buy_size*.998)/float(execution_price),tick_size)
		
    #execute maker buy with the appropriate symbol, amount, and calculated price
    buy = trader.new_order(symbol, str(amount), execution_price, "buy", ["maker-or-cancel"])
    print(f'Maker Buy: {buy}')

def lambda_handler(event, context):
    _buyBitcoin(20, public_key, private_key)
    return {
        'statusCode': 200,
        'body': json.dumps('End of script')
    }