TWS API请求参数错误时脚本冻结问题求助

问题描述 #

使用Python的IB API调用reqHistoricalData()获取历史数据时，参数正确情况下脚本可正常执行结束；但传入错误参数（例如contract.currency = 'US'）时，控制台会输出错误：

ERROR 123 321 Request validation failed. -'bS' : cause - US currency is not allowed

但脚本会无限挂起，必须手动停止才能终止。

问题原因 #

代码中通过while not app.data_end:循环等待数据获取完成，而data_end仅在historicalDataEnd回调中被设置为True。当参数验证失败时，TWS不会触发historicalDataEnd回调，导致data_end始终为False，循环无限执行。

解决方案 #

1. 实现error回调捕获请求错误 #

重写EWrapper的error方法，捕获TWS返回的错误信息，并触发终止循环的条件。

2. 添加超时机制 #

为等待循环设置超时时间，避免因异常情况（如网络问题导致错误回调未触发）导致脚本永久挂起。

修改后的代码示例 #

from ibapi.client import EClient
from ibapi.wrapper import EWrapper
from ibapi.contract import Contract
from ibapi.order import Order
import pandas as pd
import threading
import time


class IBapi(EWrapper, EClient):
    def __init__(self):
        EClient.__init__(self, self)
        self.open_orders = list()
        self.historical_data = list()
        self.df = None
        self.data_end = False
        self.error_occurred = False  # 标记是否发生错误
        self.error_msg = ""  # 存储错误信息

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

    def openOrder(self, orderId, contract, order, orderState):
        self.open_orders.append(('OpenOrder ID:', orderId, contract.symbol, contract.secType, '@',
                                 contract.exchange, ':', order.action, order.orderType, order.totalQuantity,
                                 orderState.status))

    def historicalData(self, reqId, bar):
        self.historical_data.append(vars(bar))

    def historicalDataUpdate(self, reqId, bar):
        line = vars(bar)
        self.df.loc[pd.to_datetime(line.pop('date'))] = line

    def historicalDataEnd(self, reqId: int, start: str, end: str):
        self.df = pd.DataFrame(self.historical_data)
        self.data_end = True

    def error(self, reqId, errorCode, errorString):
        print(f"ERROR {reqId} {errorCode} {errorString}")
        # 针对历史数据请求的错误（reqId=123），触发终止条件
        if reqId == 123:
            self.error_occurred = True
            self.data_end = True
            self.error_msg = errorString


class Connect:
    app = None

    def __init__(self):
        self.app = IBapi()
        self.app.connect('127.0.0.1', 7497, 123)

        api_thread = threading.Thread(target=self.run_loop, daemon=True)
        api_thread.start()

        time.sleep(1)
        print('Соединились')

    def run_loop(self):
        self.app.run()


def get_historical_data(symbol, sectype, exchange, currency, duration=None, barsize=None,
                        whattoshow=None, enddatetime=None, userth=None, format_date=None) -> list:
    print('\nGET HISTORY\n-------------------------------')

    app = Connect().app

    contract = Contract()
    contract.symbol = symbol
    contract.secType = sectype
    contract.exchange = exchange
    contract.currency = currency

    format_date = format_date or 1
    enddatetime = enddatetime or ''
    barsize = barsize or '1 hour'
    duration = duration or '1 D'
    whattoshow = whattoshow or 'BID'
    userth = userth or 1

    app.reqHistoricalData(reqId=123, contract=contract, endDateTime=enddatetime, durationStr=duration,
                          barSizeSetting=barsize, whatToShow=whattoshow, useRTH=userth, formatDate=format_date,
                          keepUpToDate=False, chartOptions=[])

    # 带超时的等待循环
    start_time = time.time()
    timeout = 10  # 自定义超时时间（秒）
    while not app.data_end:
        time.sleep(1)
        if time.time() - start_time > timeout:
            print("请求超时，终止循环")
            app.data_end = True
            app.error_occurred = True
            app.error_msg = "请求超时"

    # 根据状态返回结果或错误提示
    if app.error_occurred:
        print(f"请求失败: {app.error_msg}")
        result = []
    else:
        result = app.df.to_dict('records')
        print(result)

    app.disconnect()
    return result


if __name__ == '__main__':
    # get_historical_data(symbol='EUR', sectype='CASH', exchange='IDEALPRO', currency='USD')
    get_historical_data(symbol='EUR', sectype='CASH', exchange='IDEALPRO', currency='US')  # 错误参数测试

关键修改说明 #

• 新增错误处理回调：通过error方法捕获请求错误，当对应reqId的历史数据请求出错时，设置data_end=True终止等待循环，并记录错误信息。
• 超时机制：设置固定超时时间，避免因异常情况导致脚本永久挂起。
• 错误状态判断：在返回结果前判断是否发生错误，返回对应空列表或错误提示，保证脚本流程正常结束。

内容的提问来源于stack exchange，提问作者Eldellano