python how to raise Exception without breaking a while loop
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lets say I have some event listener that suppose to run all the time and there is some exceptions that I want to pass them to the function caller something like that
import asyncio
_ = 0
async def listener(loop):
while True:
await asyncio.sleep(0.5)
if _ != 0:
raise ValueError('the _ is not 0 anymore!')
print('okay')
async def executor(loop):
while True:
x = await loop.run_in_executor(None, input, 'execute: ')
global _
_ = x
async def main(loop):
asyncio.ensure_future(listener(loop), loop=loop)
await executor(loop)
loop = asyncio.get_event_loop()
loop.run_until_complete(main(loop))
if you gonna change the value the listener event loop will brake but I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
python-3.x asynchronous exception-handling python-asyncio
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
add a comment |
lets say I have some event listener that suppose to run all the time and there is some exceptions that I want to pass them to the function caller something like that
import asyncio
_ = 0
async def listener(loop):
while True:
await asyncio.sleep(0.5)
if _ != 0:
raise ValueError('the _ is not 0 anymore!')
print('okay')
async def executor(loop):
while True:
x = await loop.run_in_executor(None, input, 'execute: ')
global _
_ = x
async def main(loop):
asyncio.ensure_future(listener(loop), loop=loop)
await executor(loop)
loop = asyncio.get_event_loop()
loop.run_until_complete(main(loop))
if you gonna change the value the listener event loop will brake but I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
python-3.x asynchronous exception-handling python-asyncio
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
add a comment |
lets say I have some event listener that suppose to run all the time and there is some exceptions that I want to pass them to the function caller something like that
import asyncio
_ = 0
async def listener(loop):
while True:
await asyncio.sleep(0.5)
if _ != 0:
raise ValueError('the _ is not 0 anymore!')
print('okay')
async def executor(loop):
while True:
x = await loop.run_in_executor(None, input, 'execute: ')
global _
_ = x
async def main(loop):
asyncio.ensure_future(listener(loop), loop=loop)
await executor(loop)
loop = asyncio.get_event_loop()
loop.run_until_complete(main(loop))
if you gonna change the value the listener event loop will brake but I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
python-3.x asynchronous exception-handling python-asyncio
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
lets say I have some event listener that suppose to run all the time and there is some exceptions that I want to pass them to the function caller something like that
import asyncio
_ = 0
async def listener(loop):
while True:
await asyncio.sleep(0.5)
if _ != 0:
raise ValueError('the _ is not 0 anymore!')
print('okay')
async def executor(loop):
while True:
x = await loop.run_in_executor(None, input, 'execute: ')
global _
_ = x
async def main(loop):
asyncio.ensure_future(listener(loop), loop=loop)
await executor(loop)
loop = asyncio.get_event_loop()
loop.run_until_complete(main(loop))
if you gonna change the value the listener event loop will brake but I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
python-3.x asynchronous exception-handling python-asyncio
python-3.x asynchronous exception-handling python-asyncio
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
asked Nov 23 '18 at 18:56
dsal3389dsal3389
127112
127112
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
If you want to raise the error but keep going, then the listener shouldn't raise directly. Instead, it should signal the exception to the interesting parties using a Future object. Instead of awaiting the executor, main() should await the broadcast future in a loop:
import asyncio
_ = 0
broadcast = None
async def listener():
while True:
await asyncio.sleep(0.5)
if _ != 0:
broadcast.set_exception(ValueError('the _ is not 0 anymore!'))
else:
print('okay')
async def executor():
loop = asyncio.get_event_loop()
while True:
x = int(await loop.run_in_executor(None, input, 'execute: '))
global _
_ = x
async def main():
global broadcast
loop = asyncio.get_event_loop()
loop.create_task(listener())
loop.create_task(executor())
while True:
broadcast = loop.create_future()
try:
await broadcast
except ValueError as e:
print('got error', e)
asyncio.get_event_loop().run_until_complete(main())
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
If you want to raise the error but keep going, then the listener shouldn't raise directly. Instead, it should signal the exception to the interesting parties using a Future object. Instead of awaiting the executor, main() should await the broadcast future in a loop:
import asyncio
_ = 0
broadcast = None
async def listener():
while True:
await asyncio.sleep(0.5)
if _ != 0:
broadcast.set_exception(ValueError('the _ is not 0 anymore!'))
else:
print('okay')
async def executor():
loop = asyncio.get_event_loop()
while True:
x = int(await loop.run_in_executor(None, input, 'execute: '))
global _
_ = x
async def main():
global broadcast
loop = asyncio.get_event_loop()
loop.create_task(listener())
loop.create_task(executor())
while True:
broadcast = loop.create_future()
try:
await broadcast
except ValueError as e:
print('got error', e)
asyncio.get_event_loop().run_until_complete(main())
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
add a comment |
I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
If you want to raise the error but keep going, then the listener shouldn't raise directly. Instead, it should signal the exception to the interesting parties using a Future object. Instead of awaiting the executor, main() should await the broadcast future in a loop:
import asyncio
_ = 0
broadcast = None
async def listener():
while True:
await asyncio.sleep(0.5)
if _ != 0:
broadcast.set_exception(ValueError('the _ is not 0 anymore!'))
else:
print('okay')
async def executor():
loop = asyncio.get_event_loop()
while True:
x = int(await loop.run_in_executor(None, input, 'execute: '))
global _
_ = x
async def main():
global broadcast
loop = asyncio.get_event_loop()
loop.create_task(listener())
loop.create_task(executor())
while True:
broadcast = loop.create_future()
try:
await broadcast
except ValueError as e:
print('got error', e)
asyncio.get_event_loop().run_until_complete(main())
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
add a comment |
I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
If you want to raise the error but keep going, then the listener shouldn't raise directly. Instead, it should signal the exception to the interesting parties using a Future object. Instead of awaiting the executor, main() should await the broadcast future in a loop:
import asyncio
_ = 0
broadcast = None
async def listener():
while True:
await asyncio.sleep(0.5)
if _ != 0:
broadcast.set_exception(ValueError('the _ is not 0 anymore!'))
else:
print('okay')
async def executor():
loop = asyncio.get_event_loop()
while True:
x = int(await loop.run_in_executor(None, input, 'execute: '))
global _
_ = x
async def main():
global broadcast
loop = asyncio.get_event_loop()
loop.create_task(listener())
loop.create_task(executor())
while True:
broadcast = loop.create_future()
try:
await broadcast
except ValueError as e:
print('got error', e)
asyncio.get_event_loop().run_until_complete(main())
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
I dont want it to break I want it to raise the error so you will be able to catch it and the loop to keep going
If you want to raise the error but keep going, then the listener shouldn't raise directly. Instead, it should signal the exception to the interesting parties using a Future object. Instead of awaiting the executor, main() should await the broadcast future in a loop:
import asyncio
_ = 0
broadcast = None
async def listener():
while True:
await asyncio.sleep(0.5)
if _ != 0:
broadcast.set_exception(ValueError('the _ is not 0 anymore!'))
else:
print('okay')
async def executor():
loop = asyncio.get_event_loop()
while True:
x = int(await loop.run_in_executor(None, input, 'execute: '))
global _
_ = x
async def main():
global broadcast
loop = asyncio.get_event_loop()
loop.create_task(listener())
loop.create_task(executor())
while True:
broadcast = loop.create_future()
try:
await broadcast
except ValueError as e:
print('got error', e)
asyncio.get_event_loop().run_until_complete(main())
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
answered Nov 23 '18 at 23:23
user4815162342user4815162342
64.8k596151
64.8k596151
add a comment |
add a comment |
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