Add two functions to buy and sell investment funds

[tux2000]

This should fix #31

Adds two new functions:

• place_order_buy_fund
• place_order_sell_fund

Example code:

ed = avanza.place_order_buy_fund(
    account_id='<accountid>',
    order_book_id = "56127",
    amount = 1000)
print(json.dumps(ed, indent=2, sort_keys=True))

order = ed["orderId"]

time.sleep(1)

ed = avanza.delete_order(account_id="<accountid>", order_id=order)

print(json.dumps(ed, indent=2, sort_keys=True))

time.sleep(5)

######################################

ed = avanza.place_order_sell_fund(
    account_id='<accountid>',
    order_book_id = "56127",
    volume = 2)
print(json.dumps(ed, indent=2, sort_keys=True))

order = ed["orderId"]

time.sleep(1)

ed = avanza.delete_order(account_id="<accountid>", order_id=order)

print(json.dumps(ed, indent=2, sort_keys=True))

Not sure if this is the optimal solution but since buy and sell are working with different parameters (amount vs volume) having a universal function might be confusing too.

[warna720]

Maybe the two functions can be merged e.g. place_order_fund with a OrderType argument since its only the route path which diffs?

[tux2000]

Nja, buy is sending the order amount in SEK in the payload while sell is sending the order volume in number of shares in the payload. Having logic within the function that converts volume (shares) to amount (SEK) will add complexity and reduce flexibility.

An alternative might be to have a universal function that accepts both volume and amount with None as default plus Ordertype as argument. Then some logic within the function could only use the appropriate argument and potentially convert between units but users might get more easily confused.

So: not sure what the optimal solution is

[warna720]

I think current solution makes the caller observant of the amount/volume diff, which i prefer over having it hidden inside. Maybe we can try to RE it and call Avanza API with amount in sell, if that works then it would be nice

[tux2000]

Maybe we can try to RE it and call Avanza API with amount in sell, if that works then it would be nice

I tested sending an entry "amount" in the payload for the sell request. It resulted in an error 400 requests.exceptions.HTTPError: 400 Client Error: Bad Request for url: https://www.avanza.se/_api/fund-guide/fund-order-page/sell

[warna720]

Alright. LGTM then.

[Qluxzz]

Thanks for helping out!