No ability to trade "post only" (commission free)

[remarqUK]

The buy / post functions are missing the optional post_only flag. e.g:

{ "id": "d0c5340b-6d6c-49d9-b567-48c4bfca13d2", "price": "0.10000000", "size": "0.01000000", "product_id": "BTC-USD", "side": "buy", "stp": "dc", "type": "limit", "time_in_force": "GTC", "post_only": false, "created_at": "2016-12-08T20:02:28.53864Z", "fill_fees": "0.0000000000000000", "filled_size": "0.00000000", "executed_value": "0.0000000000000000", "status": "pending", "settled": false }

As per the GDAX API docs:

https://docs.gdax.com/#orders

'Post Only' will ensure that the order is only executed if the entire order can be posted to the order book.

If any part of the order crosses the spread to fill an existing order, an error will be displayed and the order will not be executed. This is useful for guaranteeing that the entire order is subject to a 0% maker order fee rate.

[justinalick]

When you call the buy or sell method in the Trader class, you can pass an argument to post only: post_only=True