[UX, Sim, Trader] DRY violations in specifying exchange

[trentmc]

The issue

Here's a snippet from ppss.yaml:

trader_ss:
  feed: binance BTC/USDT c 5m
  sim_only:
    buy_amt: 1000 USD # buy this amount in each epoch
    fee_percent: 0.0 # simulated % fee
    init_holdings:
      - 100000 USDT
      - 2 BTC
  bot_only:
    min_buffer: 30 # in s. only trade if there's > this time left
    max_tries: 10 # max no. attempts to process a feed
    position_size: 3 # buy/sell this amount in each epoch
  exchange_only:
    timeout: 30000
    options:
      createMarketBuyOrderRequiresPrice": False
      defaultType: spot

sim_ss: # sim only
  do_plot: True
  log_dir: logs
  final_img_filebase: final_img # for name log_dir/{final_img_filebase}_{NR}.png
  test_n: 5000 # number of epochs to simulate
  tradetype: histmock # histmock | livemock | livereal
  exchange_only:
    timeout: 30000
    options:
      createMarketBuyOrderRequiresPrice": False
      defaultType: spot

The problem: exchange_only and its sub-values are in two places.

This gets reflected further downstream too.

This is a DRY violation. And, it's annoying from a UX perspective too: the user should really only have to change one place.

Candidate solutions

1. Create a new module ExchangeSS that has exchange_only and all the info below that. Then, both Trader and Simulator see this
2. Only have the info in TraderSS. Then, SimulatorSS also uses the info

TODO

• Quick implementation experiment trying cand (1): will it be clean?
• If yes to ^, build (1). Else build (2)