Getting order Id error when running Ibapi / TWS API script

Question

I'm running a test code that is supposed to place a simple order only, but every time I run it I'm getting a weird error that I've never experienced before. Here is a screenshot https://imgur.com/a/vuPfsys . And this is my script: Help would be really appreciated...

from ibapi.client import EClient
from ibapi.wrapper import EWrapper
from ibapi.contract import Contract
from ibapi.order import *

import threading
import time

class IBapi(EWrapper, EClient):
    
    def __init__(self):
        EClient.__init__(self, self)
    
    def nextValidId(self, orderId: int):
        super().nextValidId(orderId)
        self.nextorderId = orderId
        print('The next valid order id is: ', self.nextorderId)

    def execDetails(self, reqId, contract, execution):
        print('Order Executed: ', reqId, contract.symbol, contract.secType, contract.currency, execution.execId, execution.orderId, execution.shares)


def run_loop():
    app.run()

def makeContract():
    contract = Contract()
    contract.symbol = 'AAPL'
    contract.secType = 'STK'
    contract.exchange = 'SMART'
    contract.currency = 'USD'
    return contract

app = IBapi()
app.connect('127.0.0.1', 7497, 999)

app.nextorderId = None

#Start the socket in a thread
api_thread = threading.Thread(target=run_loop, daemon=True)
api_thread.start()

#Check if the API is connected via orderid
while True:
    if isinstance(app.nextorderId, int):
        print('connected')
        print()
        break
    else:
        print('waiting for connection')
        time.sleep(1)

#Create order object
order = Order()
order.action = 'BUY'
order.totalQuantity = 2000
order.orderType = 'MKT'
order.orderId = app.nextorderId
app.nextorderId += 1



#Place order
app.placeOrder(order.orderId, makeContract, order)

#wait for callbacks
time.sleep(20)

app.disconnect()

Thank you so much

Answer 1

You probably want to call the function makeContract. You're passing the function object instead of the result.

app.placeOrder(order.orderId, makeContract(), order)

Note the parentheses.