async def iter(self):
async with self.running():
# Common kwargs to all middleware handlers.
kwargs = {"events": self}
async with AsyncExitStack() as stack:
enter = stack.enter_async_context
agen = await enter(aitercontext(self.root()))
# Construct the middleware pipeline.
if self.batch_args:
agen = await enter(
aitercontext(
Take(*self.batch_args).handler(agen, **kwargs)))
# User-provided middleware, which must handle and yield either single
# events or a batch.
for m in self.executor.processor.middleware:
agen = await enter(aitercontext(m.handler(agen, **kwargs)))
# Acknowledgement handling.
agen = await enter(aitercontext(Ack().handler(agen, **kwargs)))
# Automatic deserialisation.
if self.want == "records":
agen = await enter(
aitercontext(Deserialize().handler(agen, **kwargs)))
# It begins.
async for x in agen:
try:
yield x
except GeneratorExit:
logger.warning("events-iter-exit")
return
async def test_aitercontext(event_loop):
async def agen():
for x in range(5):
await asyncio.sleep(1)
yield x
with event_loop.assert_cleanup():
async with aitercontext(agen()) as safe_gen:
it = iter(range(5))
async for item in safe_gen:
assert item == next(it)
assert event_loop.steps == [1] * 5
with pytest.raises(RuntimeError):
await anext(safe_gen)
with pytest.raises(RuntimeError):
async with safe_gen:
pass
safe_gen = aitercontext(agen())
with pytest.warns(UserWarning):
await anext(safe_gen)
with pytest.raises(TypeError):
AsyncIteratorContext(None)
with pytest.raises(TypeError):
AsyncIteratorContext(safe_gen)
async def test_not_an_agen_in_aitercontext(event_loop):
async with aitercontext(not_an_agen([1])) as safe_gen:
async for item in safe_gen:
assert item == 1
with pytest.raises(ZeroDivisionError):
async with aitercontext(not_an_agen([1])) as safe_gen:
async for item in safe_gen:
1/0
async def test_not_an_agen_in_aitercontext(event_loop):
async with aitercontext(not_an_agen([1])) as safe_gen:
async for item in safe_gen:
assert item == 1
with pytest.raises(ZeroDivisionError):
async with aitercontext(not_an_agen([1])) as safe_gen:
async for item in safe_gen:
1 / 0
async def test_silence_exception_in_aitercontext(event_loop):
async with aitercontext(silence_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1/0
# Silencing a generator exit is forbidden
with pytest.raises(GeneratorExit):
async with aitercontext(silence_agen()) as safe_gen:
async for _ in safe_gen:
raise GeneratorExit
async def test_silence_exception_in_aitercontext(event_loop):
async with aitercontext(silence_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1 / 0
# Silencing a generator exit is forbidden
with pytest.raises(GeneratorExit):
async with aitercontext(silence_agen()) as safe_gen:
async for _ in safe_gen:
raise GeneratorExit
async def test_reraise_exception_in_aitercontext(event_loop):
with pytest.raises(RuntimeError) as info:
async with aitercontext(reraise_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1/0
assert type(info.value.__cause__) is ZeroDivisionError
with pytest.raises(RuntimeError) as info:
async with aitercontext(reraise_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
raise GeneratorExit
assert type(info.value.__cause__) is GeneratorExit
async def test_reraise_exception_in_aitercontext(event_loop):
with pytest.raises(RuntimeError) as info:
async with aitercontext(reraise_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1 / 0
assert type(info.value.__cause__) is ZeroDivisionError
with pytest.raises(RuntimeError) as info:
async with aitercontext(reraise_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
raise GeneratorExit
assert type(info.value.__cause__) is GeneratorExit
async def test_athrow_in_aitercontext(event_loop):
async with aitercontext(agen()) as safe_gen:
assert await safe_gen.__anext__() == 0
with pytest.raises(ZeroDivisionError):
await safe_gen.athrow(ZeroDivisionError())
async for _ in safe_gen:
assert False # No more items
async def test_stuck_in_aitercontext(event_loop):
with pytest.raises(RuntimeError) as info:
async with aitercontext(stuck_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1 / 0
assert "didn't stop after athrow" in str(info.value)
with pytest.raises(RuntimeError) as info:
async with aitercontext(stuck_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
raise GeneratorExit
# GeneratorExit relies on aclose, not athrow
# The message is a bit different
assert "async generator ignored GeneratorExit" in str(info.value)
async def test_simple_aitercontext(event_loop):
async with aitercontext(agen()) as safe_gen:
# Cannot enter twice
with pytest.raises(RuntimeError):
async with safe_gen:
pass
it = iter(range(5))
async for item in safe_gen:
assert item == next(it)
assert event_loop.steps == [1] * 5
# Exiting is idempotent
await safe_gen.__aexit__(None, None, None)
await safe_gen.aclose()
with pytest.raises(RuntimeError):
await anext(safe_gen)
with pytest.raises(RuntimeError):
async with safe_gen:
pass
with pytest.raises(RuntimeError):
await safe_gen.athrow(ValueError())
async def test_stuck_in_aitercontext(event_loop):
with pytest.raises(RuntimeError) as info:
async with aitercontext(stuck_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
1/0
assert "didn't stop after athrow" in str(info.value)
with pytest.raises(RuntimeError) as info:
async with aitercontext(stuck_agen()) as safe_gen:
async for item in safe_gen:
assert item == 1
raise GeneratorExit
# GeneratorExit relies on aclose, not athrow
# The message is a bit different
assert "async generator ignored GeneratorExit" in str(info.value)
async def test_athrow_in_aitercontext(event_loop):
async with aitercontext(agen()) as safe_gen:
assert await safe_gen.__anext__() == 0
with pytest.raises(ZeroDivisionError):
await safe_gen.athrow(ZeroDivisionError())
async for _ in safe_gen:
assert False # No more items
async def test_aitercontext_wrong_usage(event_loop):
safe_gen = aitercontext(agen())
with pytest.warns(UserWarning):
await anext(safe_gen)
with pytest.raises(TypeError):
AsyncIteratorContext(None)
with pytest.raises(TypeError):
AsyncIteratorContext(safe_gen)
async def test_aitercontext_wrong_usage(event_loop):
safe_gen = aitercontext(agen())
with pytest.warns(UserWarning):
await anext(safe_gen)
with pytest.raises(TypeError):
AsyncIteratorContext(None)
with pytest.raises(TypeError):
AsyncIteratorContext(safe_gen)
async def test_aitercontext(event_loop):
async def agen():
for x in range(5):
await asyncio.sleep(1)
yield x
with event_loop.assert_cleanup():
async with aitercontext(agen()) as safe_gen:
it = iter(range(5))
async for item in safe_gen:
assert item == next(it)
assert event_loop.steps == [1] * 5
with pytest.raises(RuntimeError):
await anext(safe_gen)
with pytest.raises(RuntimeError):
async with safe_gen:
pass
with pytest.raises(RuntimeError):
await safe_gen.athrow(ValueError())
with event_loop.assert_cleanup():
async with aitercontext(agen()) as safe_gen:
assert await safe_gen.__anext__() == 0
with pytest.raises(ZeroDivisionError):
await safe_gen.athrow(ZeroDivisionError())
async for item in safe_gen:
assert False # No more items
safe_gen = aitercontext(agen())
with pytest.warns(UserWarning):
await anext(safe_gen)
with pytest.raises(TypeError):
AsyncIteratorContext(None)
with pytest.raises(TypeError):
AsyncIteratorContext(safe_gen)
async def test_raise_in_aitercontext(event_loop):
with pytest.raises(ZeroDivisionError):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
1 / 0
with pytest.raises(ZeroDivisionError):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
pass
1 / 0
with pytest.raises(GeneratorExit):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
raise GeneratorExit
with pytest.raises(GeneratorExit):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
pass
raise GeneratorExit
async def test_raise_in_aitercontext(event_loop):
with pytest.raises(ZeroDivisionError):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
1/0
with pytest.raises(ZeroDivisionError):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
pass
1/0
with pytest.raises(GeneratorExit):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
raise GeneratorExit
with pytest.raises(GeneratorExit):
async with aitercontext(agen()) as safe_gen:
async for _ in safe_gen:
pass
raise GeneratorExit
async def test_simple_aitercontext(event_loop):
async with aitercontext(agen()) as safe_gen:
it = iter(range(5))
async for item in safe_gen:
assert item == next(it)
assert event_loop.steps == [1]*5
# Exiting is idempotent
await safe_gen.__aexit__(None, None, None)
await safe_gen.aclose()
with pytest.raises(RuntimeError):
await anext(safe_gen)
with pytest.raises(RuntimeError):
async with safe_gen:
pass
with pytest.raises(RuntimeError):
await safe_gen.athrow(ValueError())