Python中的併發線程

Question

我遇到了3個線程同時運行的問題。我希望「交易」循環，「價格」循環和「停止」循環同時運行，但似乎「停止」循環劫持程序並在其他人等待輪到時運行。我應該如何設置它們以便它們全部同時運行？

import Queue 
import threading 
import time 
import json 

from execution import Execution 
from settings import STREAM_DOMAIN, API_DOMAIN, ACCESS_TOKEN, ACCOUNT_ID 
from strategy import TestRandomStrategy 
from streaming import StreamingForexPrices 
from event import TickEvent 
from rates import stop 



def trade(events, strategy, execution): 
    """ 
    Carries out an infinite while loop that polls the 
    events queue and directs each event to either the 
    strategy component of the execution handler. The 
    loop will then pause for "heartbeat" seconds and 
    continue. 
    """ 
    while True: 
     try: 
      event = events.get(False) 
     except Queue.Empty: 
      pass 
     else: 
      if event is not None: 
       if event.type == 'TICK': 
        strategy.calculate_signals(event) 
       elif event.type == 'ORDER': 
        print "Executing order!" 
        execution.execute_order(event) 
     time.sleep(heartbeat) 


if __name__ == "__main__": 
    heartbeat = 0 # Half a second between polling 
    events = Queue.Queue() 

    # Trade 1000 unit of EUR/USD 
    instrument = "EUR_USD" 
    units = 1 
    stopLoss = stopper 




    # Create the OANDA market price streaming class 
    # making sure to provide authentication commands 
    prices = StreamingForexPrices(
     STREAM_DOMAIN, ACCESS_TOKEN, ACCOUNT_ID, 
     instrument, events 
    ) 
    #handle stopLoss price 
    stopper = stop() 

    # Create the execution handler making sure to 
    # provide authentication commands 
    execution = Execution(API_DOMAIN, ACCESS_TOKEN, ACCOUNT_ID) 

    # Create the strategy/signal generator, passing the 
    # instrument, quantity of units and the events queue 
    strategy = TestRandomStrategy(instrument, units, events, stopLoss) 

    # Create two separate threads: One for the trading loop 
    # and another for the market price streaming class 
    trade_thread = threading.Thread(target=trade, args=(events, strategy, execution)) 
    price_thread = threading.Thread(target=prices.stream_to_queue, args=[]) 
    rate_thread = threading.Thread(target=stop, args=[]) 

    # Start both threads 
    trade_thread.start() 
    price_thread.start() 
    rate_thread.start() 

只是fyi，一切都很好，直到我試圖添加「率」。我添加的唯一東西是一個額外的線程，stopLoss和rate.py文件。

rate.py：

import oandapy 
import time 
oanda = oandapy.API(environment="practice", access_token="xxxxxxxxx") 


while True: 
    response = oanda.get_prices(instruments="EUR_USD") 
    prices = response.get("prices") 
    asking_price = prices[0].get("ask") 
    stop = asking_price - .001 
    print stop 
    time.sleep(1) 

感謝您的幫助提前！

Answer 1

首先，一句話：

• 不使用sleep如果你能避免它;例如，在「以舊換新」循環您 不需要睡覺的，如果你在你的隊列進行阻斷.get()

然後，一旦「rates.py」導入它開始while循環;你 缺少stop()函數（或者你的代碼不完整？）

編輯：如果你想添加在rates.py的stop功能，只是把 的while循環代碼def stop():塊內這樣

def stop(): 
    while True: 
     response = oanda.get_prices(instruments="EUR_USD") 
     prices = response.get("prices") 
     asking_price = prices[0].get("ask") 
     stop = asking_price - .001 
     print stop 
     time.sleep(1) 

（順便說一句：你真的知道你在做什麼）