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			73 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			73 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| __all__ = 'run',
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| 
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| from . import coroutines
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| from . import events
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| from . import tasks
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| 
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| 
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| def run(main, *, debug=False):
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|     """Execute the coroutine and return the result.
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| 
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|     This function runs the passed coroutine, taking care of
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|     managing the asyncio event loop and finalizing asynchronous
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|     generators.
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| 
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|     This function cannot be called when another asyncio event loop is
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|     running in the same thread.
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| 
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|     If debug is True, the event loop will be run in debug mode.
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| 
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|     This function always creates a new event loop and closes it at the end.
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|     It should be used as a main entry point for asyncio programs, and should
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|     ideally only be called once.
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| 
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|     Example:
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| 
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|         async def main():
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|             await asyncio.sleep(1)
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|             print('hello')
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| 
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|         asyncio.run(main())
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|     """
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|     if events._get_running_loop() is not None:
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|         raise RuntimeError(
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|             "asyncio.run() cannot be called from a running event loop")
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| 
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|     if not coroutines.iscoroutine(main):
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|         raise ValueError("a coroutine was expected, got {!r}".format(main))
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| 
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|     loop = events.new_event_loop()
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|     try:
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|         events.set_event_loop(loop)
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|         loop.set_debug(debug)
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|         return loop.run_until_complete(main)
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|     finally:
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|         try:
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|             _cancel_all_tasks(loop)
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|             loop.run_until_complete(loop.shutdown_asyncgens())
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|             loop.run_until_complete(loop.shutdown_default_executor())
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|         finally:
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|             events.set_event_loop(None)
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|             loop.close()
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| 
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| 
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| def _cancel_all_tasks(loop):
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|     to_cancel = tasks.all_tasks(loop)
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|     if not to_cancel:
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|         return
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| 
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|     for task in to_cancel:
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|         task.cancel()
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| 
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|     loop.run_until_complete(
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|         tasks.gather(*to_cancel, loop=loop, return_exceptions=True))
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| 
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|     for task in to_cancel:
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|         if task.cancelled():
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|             continue
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|         if task.exception() is not None:
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|             loop.call_exception_handler({
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|                 'message': 'unhandled exception during asyncio.run() shutdown',
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|                 'exception': task.exception(),
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|                 'task': task,
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|             })
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