def test_process_running_as_context_manager():
"""Checks that an already running process can be used as a context manager"""
n1 = pyzmp.CoProcess()
n1.start()
with n1: # hooking to an already started process
# This might restart the process (might be bad but ideally should not matter.)
assert n1.is_alive()
assert not n1.is_alive()
def test_process_termination():
"""Checks that a process can be shutdown without being started and indicate that it never ran"""
n1 = pyzmp.CoProcess()
assert not n1.is_alive()
exitcode = n1.shutdown(
) # shutdown should have no effect here (if not started, same as noop )
assert exitcode is None # exitcode should be None (process didn't start and didn't stop so no exit code)
assert not n1.is_alive()
def test_context_before_started():
"""Checks that a coprocess initializes its context before starting """
mgr = multiprocessing.Manager()
# creating namespace proxy (see https://docs.python.org/3/library/multiprocessing.html#proxy-objects)
ns = mgr.Namespace()
mypid = os.getpid()
# We can use the context to setup the value in the namespace
@contextlib.contextmanager
def ctxtuser(intval, *args, **kwargs):
# to make sure we are in another process
assert os.getpid() != mypid
# ns is referenced in this closure and proxy has been passed to child process
ns.kwarg = intval
yield ns
ns.kwarg = None # to make sure we exit before shutdown returns
def kwarguser(
ns, intval, *args, **kwargs
): # kwargs is there to accept extra arguments nicely (timedelta)
ns.kwarg -= intval
ns.call = ns.call + 1 if hasattr(ns, 'call') else 1 # first call is 1
return ns.kwarg
n1 = pyzmp.CoProcess(kwargs={
'intval': 42,
},
target=kwarguser,
context_manager=ctxtuser)
assert not n1.is_alive()
# here the context has NOT already been entered
assert not hasattr(ns, 'kwarg')
svc_url = n1.start()
assert n1.is_alive()
assert svc_url
# here the context HAS BEEN entered
assert hasattr(ns, 'kwarg')
# MAYBE update has NOT already been called
# Note we want to keep indeterminism here, as linearizability of events should only be enforced
# via context manager with the usual method/procedure call API.
# other events could potentially be completely asynchronous (might depend on OS / process interface)
assert ns.kwarg in [42, 0]
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
# update HAS been called once (or more), and context has been exited
assert ns.call >= 1
assert ns.kwarg is None
def test_process_timeout_creation_termination():
"""Checks that a process can be started with timeout and shutdown and indicate that it ran successfully"""
n1 = pyzmp.CoProcess()
assert not n1.is_alive()
svc_url = n1.start(1)
assert svc_url
assert n1.is_alive()
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
def test_process_creation_termination():
"""Checks that a process can be started and shutdown and indicate that it ran successfully"""
n1 = pyzmp.CoProcess()
assert not n1.is_alive()
svc_url = n1.start()
assert n1.is_alive()
assert svc_url
exitcode = n1.shutdown()
assert exitcode == 0 # default process should spin without issues
assert not n1.is_alive()
def test_process_creation_double_termination():
"""Checks that a process can be started and shutdown twice and indicate that it ran successfully"""
n1 = pyzmp.CoProcess()
assert not n1.is_alive()
svc_url1 = n1.start()
assert n1.is_alive()
assert svc_url1
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
exitcode = n1.shutdown()
assert exitcode == 0 # the exit code is still 0 since we didn't restart...
assert not n1.is_alive()
def test_process_double_creation_termination():
"""Checks that a process can be started twice and shutdown and indicate that it ran successfully"""
n1 = pyzmp.CoProcess()
assert not n1.is_alive()
svc_url1 = n1.start()
assert n1.is_alive()
assert svc_url1
svc_url2 = n1.start() # this shuts down properly and restart the process
assert n1.is_alive()
assert svc_url2
# the process is the same (same id) so we should get same url
assert svc_url1 == svc_url2
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
def test_process_creation_args_delegate():
"""Checks that a process can be passed an argument using delegation"""
ns = multiprocessing.Manager().Namespace()
ns.arg = 42
def arguser(
fortytwo, **kwargs
): # kwargs is there to accept extra arguments nicely (timedelta)
ns.arg -= fortytwo
return ns.arg
n1 = pyzmp.CoProcess(args=(ns.arg, ), target=arguser)
assert not n1.is_alive()
svc_url = n1.start()
assert n1.is_alive()
assert svc_url
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
assert ns.arg == 0
def test_process_creation_kwargs_delegate():
"""Checks that a process can be passed a keyword argument using delegation"""
ns = multiprocessing.Manager().Namespace()
ns.kwarg = 42
def kwarguser(
intval, **kwargs
): # kwargs is there to accept extra arguments nicely (timedelta)
ns.kwarg -= intval
return ns.kwarg
n1 = pyzmp.CoProcess(kwargs={
'intval': ns.kwarg,
}, target=kwarguser)
assert not n1.is_alive()
svc_url = n1.start()
assert n1.is_alive()
assert svc_url
exitcode = n1.shutdown()
assert exitcode == 0
assert not n1.is_alive()
assert ns.kwarg == 0
def test_process_as_context_manager():
"""Checks that a process can be used as a context manager"""
with pyzmp.CoProcess() as n1: # this will __init__ and __enter__
assert n1.is_alive()
assert not n1.is_alive()
