RuntimeError: This event loop is already running

[Fredrik-C]

I subscribe to a set of tickers as in the code below but it often fails with a "This event loop is already running" error. My hunch it happens when the event callbacks get triggered simultaniously.

bars_dictionary = {}
def start_session():
    global ib
    tickers = ['GOOGL', 'MSFT', 'NVDA', 'AAPL', 'TSLA']

    ib = IB()
    ib.connect('127.0.0.1', 4002, clientId=1)
    ib.reqMarketDataType(1)
    for ticker in tickers:
        contract = Stock(ticker, 'SMART', 'USD')
        bars_dictionary[ticker] = ib.reqHistoricalData(contract=contract, endDateTime='', barSizeSetting='5 secs', durationStr='1 D', whatToShow='TRADES', useRTH=False, keepUpToDate=True)
        bars_dictionary[ticker].updateEvent += lambda bars, hasNewBar, ticker=ticker: bars_updated(bars, hasNewBar, ticker)
        
    ib.run()

if __name__ == "__main__":
    start_session()

Callstack:

  File "c:\git\Raytail.XGBoost\ibkr_trader.py", line 106, in EnterBullTrade
    account = ib.accountSummary()
              ^^^^^^^^^^^^^^^^^^^
  File "C:\git\Raytail.XGBoost\venv\Lib\site-packages\ib_async\ib.py", line 516, in accountSummary
    return self._run(self.accountSummaryAsync(account))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\git\Raytail.XGBoost\venv\Lib\site-packages\ib_async\ib.py", line 418, in _run
    return util.run(*awaitables, timeout=self.RequestTimeout)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\git\Raytail.XGBoost\venv\Lib\site-packages\ib_async\util.py", line 360, in run
    result = loop.run_until_complete(task)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\rayta\AppData\Local\Programs\Python\Python312\Lib\asyncio\base_events.py", line 662, in run_until_complete
    self._check_running()
  File "C:\Users\rayta\AppData\Local\Programs\Python\Python312\Lib\asyncio\base_events.py", line 621, in _check_running
    raise RuntimeError('This event loop is already running')
RuntimeError: This event loop is already running

Any suggestion on how to hook up multiple updateEvent callbacks and avoid this issue?

[Fredrik-C]

Problem was here:

account = ib.accountSummary() ^^^^^^^^^^^^^^^^^^^ File "C:\git\Raytail.XGBoost\venv\Lib\site-packages\ib_async\ib.py", line 516, in accountSummary return self._run(self.accountSummaryAsync(account))

self._run seems to have caused the "This event loop is already running" problem. When I resorted to use await ib.accountSummaryAsync() instead then problem was gone.