Programming Your First Cryptobot (Part 2)

In part one of the series, we wrote a simple Python based wrapper around some of the basic Bittrex API features. In part two we will expand on this wrapper so that you can add further functionality to your trading bot.

For convenience, I have uploaded the source from part one to github.com/tmstieff/BittrexBot. If you spot an errors, please feel free to open an issue or pull request!

We can open buy and sell orders already, but at the moment we are relying Bittrex to tell us if the order went through. For various reasons the order might fail, but the most common reason for our current implementation will involve insufficient funds. To fix this, let's first check our account balances and determine if we actually have enough of a specific coin or token to sell.

Create two new functions, and add them anywhere to the body of our Python file. These will query for the balance of a specific market using our API key. Because of how the Bittrex API works, we will need to query for the market first and then using that information we can query for the balance of the market currency.

def get_balance_from_market(market_type):
    markets_res = simple_request('https://bittrex.com/api/v1.1/public/getmarkets')
    markets = markets_res['result']
    for market in markets:
        if market['MarketName'] == market_type:
            return get_balance(market['MarketCurrency'])
# Return a fake response of 0 if not found
return {'result': {'Available': 0}}

def get_balance(currency):

url = 'https://bittrex.com/api/v1.1/account/getbalance?apikey=' + API_KEY + '&currency=' + currency

res = signed_request(url)
if res['result'] is not None and len(res['result']) > 0:
    return res

# If there are no results, than your balance is 0
return {'result': {'Available': 0}}</code></pre>

Now in our tick() function, we can utilize the get_balance_from_market() function to check if we have any coins to sell before blindly placing a market sell order.
        if percent_chg < -20:
            # Do we have any to sell?
            balance_res = get_balance_from_market(market)
            current_balance = balance_res['result']['Available']
        if current_balance > 5:
            # Ship is sinking, get out!
            print('Selling 5 units of ' + market + ' for ' + str(format_float(last)))
            res = sell_limit(market, 5, last)
            print(res)
        else:
            print('Not enough ' + market + ' to open a sell order')</code></pre>

This new block of code will query for the current balance of the market in question. If we have enough to sell, a market sell order will be opened.
There's another obvious issue with our crypto bot. It will keep placing buy and sell orders no matter how many existing orders we have open! Let's use the 'getopenorders' endpoint to determine if we have any open orders for a specific market. We can use this information to limit how many orders our trader creates.

In the script add two more functions. One will make the API call, and another will parse the open orders list to determine if we have any open orders for a specific market and order type. The two order types listed on the API docs are 'LIMIT_BUY' and 'LIMIT_SELL'.
def get_open_orders(market):
    url = 'https://bittrex.com/api/v1.1/market/getopenorders?apikey=' + API_KEY + '&market=' + market
    return signed_request(url)
def has_open_order(market, order_type):

orders_res = get_open_orders(market)

orders = orders_res['result']
if orders is None or len(orders) == 0:
    return False

# Check all orders for a LIMIT_BUY
for order in orders:
    if order['OrderType'] == order_type:
        return True

return False</code></pre>

Now let's modify our tick() function again to check for any open orders before we execute a trade.
        if 40 < percent_chg < 60:
            # Fomo strikes! Let's buy some
            if has_open_order(market, 'LIMIT_BUY'):
                print('Order already opened to buy 5 ' + market)
            else:
                print('Purchasing 5 units of ' + market + ' for ' + str(format_float(last)))
                res = buy_limit(market, 5, last)
                print(res)
    if percent_chg < -20:
        # Do we have any to sell?
        balance_res = get_balance(market)
        current_balance = balance_res['result']['Available']

        if current_balance > 5:
            # Ship is sinking, get out!
            if has_open_order(market, 'LIMIT_SELL'):
                print('Order already opened to sell 5 ' + market)
            else:
                print('Selling 5 units of ' + market + ' for ' + str(format_float(last)))
                res = sell_limit(market, 5, last)
                print(res)
        else:
            print('Not enough ' + market + ' to open a sell order')</code></pre>

The changes should be pretty straightforward. If an existing order is still open for a given market, the bot will skip it and continue ticking.

Hopefully all of this doesn't seem too daunting, and you are able to expand on your crypto bot from part one. I h ave uploaded the complete code for this part to github.com/tmstieff/BittrexBot so that everyone can have a complete working copy. If you have any questions please comment below!