How to save indicator config to use in different strategy

sfkiwi

I am trying to figure out a way to save the configuration of all of my indicators in one strategy and then load the same configuration into a different strategy (there are more than 50 indicators and the indicators may change from time to time so it needs to be done programmatically).

For example, say in strategy1 I have an SMA and an RSI, I want to be able to load a file from disk that will tell strategy2 to create an SMA and an RSI with the same config (including plotname) as in Strategy1. Strategy 1 and Strategy 2 have different logic and both use different feeds so the rest of the cerebro instance is quite different between Strategy1 and Strategy2.

I had tried pickling but keep getting cannot serialize '_io.TextIOWrapper' object exceptions, which is also discussed in this thread. However pickling probably wouldn't work in any case because each indicator holds references to the cerebro context and those get pickled as well.

Is there a way to save a config, along with the indicator plotname etc that could then be used to instantiate an indentical copy in another strategy?

backtrader

There may be something missing here to let me understand your troubles:

You create and configure the indicators, i.e.: you set the values for the parameters and things like plotname

What prevents you from saving those parameters you are actually setting to a file? (pickled, in JSON Format, in .ini format, you name it)

sfkiwi

Thanks, in the end that is pretty much what I did.
There's likely a much more elegant way to do this than how I have done it though

# define_indicators.py

def save_indicators():

  indicators = {

    'SMA': {'ind': bt.ind.SMA, 'data': 0, 'args': {'period':10}},
    'trend': {'ind': bt.ind.SMA, 'data': 3, 'args': {'period':10}},
    'rsi_1M': { 'ind': bt.ind.RSI, 'data': 0, 'args': None },
    'rsi_5M': { 'ind': bt.ind.RSI, 'data': 1, 'args': None},
    'rsi_30M': { 'ind': bt.ind.RSI, 'data': 2, 'args': None },
    'rsi_1H': { 'ind': bt.ind.RSI, 'data': 3, 'args': None },
    'rsi_4H': {'ind': bt.ind.RSI, 'data': 4, 'args': None},
    'sto_1M': {'ind': StochasticRSI, 'data': 'rsi_1M', 'args': None},
    .....
  }

  DATA_DIRNAME.mkdir(parents=True, exist_ok=True)
  with open(INDICATORS_FILENAME, 'wb') as f:
    pickle.dump(indicators, f, pickle.HIGHEST_PROTOCOL)


def build_indicators(datas, indicators):

    ind = dict()
    for k, v in indicators.items():

        kwargs = {}
        if v['args']:
            kwargs = v['args']

        if type(v['data']) is str:
            data = [ind[v['data']]]
        elif type(v['data']) is list:
            data = list()
            for d in v['data']:
                if type(d) is tuple:
                    data.append(getattr(ind[d[0]], d[1]))
                else:
                    data.append(ind[d])
        else:
            data = [datas[v['data']]]
        
        ind[k] = v['ind'](*data, plotname=k, **kwargs)
    
    return ind

if __name__ == '__main__':
  save_indicators()

# strategy.py
import backtrader as bt
from define_indicators import build_indicators

class St(bt.Strategy):

  def __init__(self):

        f = open(INDICATORS_FILENAME, 'rb')
        indicators = pickle.load(f)

        self.indicators = build_indicators(self.datas, indicators)