Python Asyncio使用asyncio.run_coroutine_threadsafe不能运行新的coroutine

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1>Python Asyncio is not running new coroutine using asyncio.run_coroutine_threadsafe. Below is the code testing performed on Mac.
————————————————————————————————

import os    
import random      
import asyncio      
import logging     
from concurrent.futures import ThreadPoolExecutor      
os.environ['PYTHONASYNCIODEBUG'] = '1'      
logging.basicConfig(level=logging.WARNING)      
async def coro():      
    print("Coroutine {} is has started")      
async def main(loop):     
    print(" 1 ")    
    fut = asyncio.run_coroutine_threadsafe(coro(), loop)      
    print(f"Future  --")          
    print(" 2 ")      
    print(" Result ",fut.result())      
    print(" 3 ")      
if __name__== '__main__':      
    loop = asyncio.get_event_loop()      
    loop.set_debug(True)      
    loop.run_until_complete(main(loop))      
————————————————————————————————

Output:
Future -- <Future at 0x102a05358 state=pending>      
=============================================================================
2>The output is same when I run on a different executor also as shown below

—————————————————————————————————————
new_loop = asyncio.new_event_loop()      
new_loop.set_default_executor(ThreadPoolExecutor(max_workers=2))      
fut = asyncio.run_coroutine_threadsafe(coro(), new_loop) 
—————————————————————————————————————

样品代码。
import os      
import random      
import asyncio      
import logging      
from concurrent.futures import ThreadPoolExecutor      
os.environ['PYTHONASYNCIODEBUG'] = '1'      
logging.basicConfig(level=logging.WARNING)      
async def coro():      
    print("Coroutine {} is has started")      
async def main(loop):    
    print(" 1 ")    
    new_loop = asyncio.new_event_loop()    
    new_loop.set_default_executor(ThreadPoolExecutor(max_workers=2))    
    fut = asyncio.run_coroutine_threadsafe(coro(), new_loop)      
    print(f"Future  --")        
    print(" 2 ")      
    print(" Result ",fut.result())      
    print(" 3 ")      
if __name__== '__main__':      
    loop = asyncio.get_event_loop()    
    loop.set_debug(True)      
    loop.run_until_complete(main(loop))    
————————————————————————————————

Output:
Future  -- <Future at 0x102f5d668 state=pending>


         
          
           python


         
          
           python-asyncio


          
           
            
             From
             
              
               asyncio.run_coroutine_threadsafe
              
             
             :
            
            
             这个函数应该从不同的操作系统线程中调用，而不是在事件循环中运行的线程。
            
            async def coro():
    print("Coroutine {} is has started")
def start_coro(loop):
    fut = asyncio.run_coroutine_threadsafe(coro(), loop)
    print(fut.result())
if __name__ == "__main__":
    loop = asyncio.get_event_loop()
    loop.set_debug(True)
    Thread(target=start_coro, args=(loop,)).start()
    loop.run_forever()


          
           
            
             
              
              
               user4815162342
              
             
             
              发布于
              
              2019-12-22


          
           
            
             
              第一个代码段将一个coroutine提交到它已经运行的事件循环中。你不需要
              
               run_coroutine_threadsafe
              
              ，你可以直接调用
              
               asyncio.create_task
              
              。正如在另一个答案中提到的，
              
               run_coroutine_threadsafe
              
              的想法是，你从你的
              
               sync
              
              代码，以提交一个任务给另一个线程中运行的事件循环。