import logging
import multiprocessing
import multiprocessing.connection as connection
import os
import select
import sys
import unittest
from nose2 import events, loader, result, runner, session, util
from nose2._vendor import six
try:
from collections.abc import Sequence
except ImportError:
from collections import Sequence
log = logging.getLogger(__name__)
[docs]class MultiProcess(events.Plugin):
configSection = "multiprocess"
def __init__(self):
self.addArgument(
self.setProcs,
"N",
"processes",
"Number of processes used to run tests (0 = auto)",
)
self.testRunTimeout = self.config.as_float("test-run-timeout", 60.0)
self._procs = self.config.as_int("processes", 0)
self.setAddress(self.config.as_str("bind_address", None))
self.cases = {}
@property
def procs(self):
"""Get the appropriate number of procs for self.procs if self._procs is
0."""
if self._procs == 0:
try:
self._procs = multiprocessing.cpu_count()
except NotImplementedError:
self._procs = 1
return self._procs
@procs.setter
def procs(self, value):
"""Setter for procs property"""
if value < 0:
raise ValueError("Number of processes cannot be less than 0")
self._procs = value
def setProcs(self, num):
self.procs = int(num[0]) # FIXME merge n fix
self.register()
def setAddress(self, address):
if address is None or address.strip() == "":
address = []
else:
address = [x.strip() for x in address.split(":")[:2]]
# Background: On Windows, select.select only works on sockets. So the
# ability to select a bindable address and optionally port for the mp
# plugin was added. Pipes should support a form of select, but this
# would require using pywin32. There are alternatives but all have
# some kind of downside. An alternative might be creating a connection
# like object using a shared queue for incomings events.
self.bind_host = None
self.bind_port = 0
if sys.platform == "win32" or address:
self.bind_host = "127.116.157.163"
if address and address[0]:
self.bind_host = address[0]
self.bind_port = 0
if len(address) >= 2:
self.bind_port = int(address[1])
def pluginsLoaded(self, event):
self.addMethods("registerInSubprocess", "startSubprocess", "stopSubprocess")
def startTestRun(self, event):
event.executeTests = self._runmp
def beforeInteraction(self, event):
# prevent interactive plugins from running
event.handled = True
return False
def _runmp(self, test, result):
# flatten technically modifies a hash of test cases, let's
# only run it once per run.
flat = list(self._flatten(test))
# do not send import failures to the subprocesses, which will mangle them
# but 'run' them in the main process.
failed_import_id = "nose2.loader.LoadTestsFailure"
result_ = self.session.testResult
for testid in flat:
if testid.startswith(failed_import_id):
self.cases[testid].run(result_)
# XXX Process-Handling: The length of the filtered list needs to be
# known for _startProcs, until this can be cleaned up. This
# wasn't the best way to deal with too few tests
flat = [x for x in flat if not x.startswith(failed_import_id)]
procs = self._startProcs(len(flat))
# send one initial task to each process
for _proc, conn in procs:
if not flat:
break
caseid = flat.pop(0)
# NOTE: it throws errors on broken pipes and bad serialization
conn.send(caseid)
rdrs = [conn for proc, conn in procs if proc.is_alive()]
while flat or rdrs:
ready, _, _ = select.select(rdrs, [], [], self.testRunTimeout)
for conn in ready:
# XXX Process-Handling: If we get an EOFError on receive the
# process finished= or we lost the process and the test it was
# working on. Also do we rebuild the process?
try:
remote_events = conn.recv()
except EOFError:
# probably dead/12
log.warning("Subprocess connection closed unexpectedly")
continue
# If remote_events is None, the process exited normally,
# which should mean that we didn't any more tests for it.
if remote_events is None:
log.debug("Conn closed %s", conn)
rdrs.remove(conn)
continue
# replay events
testid, events = remote_events
log.debug("Received results for %s", testid)
for (hook, event) in events:
log.debug("Received %s(%s)", hook, event)
self._localize(event)
getattr(self.session.hooks, hook)(event)
# Send the next test_id
# NOTE: send throws errors on broken pipes and bad serialization
if not flat:
# If there are no more, send None - it's the 'done' flag
conn.send(None)
continue
caseid = flat.pop(0)
conn.send(caseid)
for _, conn in procs:
conn.close()
# ensure we wait until all processes are done before
# exiting, to allow plugins running there to finalize
for proc, _ in procs:
proc.join()
def _prepConns(self):
"""
If the ``bind_host`` is not ``None``, return:
(multiprocessing.connection.Listener, (address, port, authkey))
else:
(parent_connection, child_connection)
For the former case: ``accept`` must be called on the listener. In order
to get a ``Connection`` object for the socket.
"""
if self.bind_host is not None:
# prevent "accidental" wire crossing
authkey = os.urandom(20)
address = (self.bind_host, self.bind_port)
listener = connection.Listener(address, authkey=authkey)
return (listener, listener.address + (authkey,))
else:
return multiprocessing.Pipe()
def _acceptConns(self, parent_conn):
"""
When listener is is a :class:`connection.Listener` instance: accept the next
incoming connection. However, a timeout mechanism is needed. Since
this functionality was added to support mp over inet sockets, this method
assumes a Socket-based listen, and will accept the private _socket
member to get a low_level socket to do a select on.
"""
if isinstance(parent_conn, connection.Listener):
# ick private interface
rdrs = [parent_conn._listener._socket]
readable, _, _ = select.select(rdrs, [], [], self.testRunTimeout)
if readable:
return parent_conn.accept()
else:
raise RuntimeError("MP: Socket Connection Failed")
else:
return parent_conn
def _startProcs(self, test_count):
# Create session export
session_export = self._exportSession()
procs = []
count = min(test_count, self.procs)
log.debug("Creating %i worker processes", count)
for _ in range(0, count):
parent_conn, child_conn = self._prepConns()
proc = multiprocessing.Process(
target=procserver, args=(session_export, child_conn)
)
proc.daemon = True
proc.start()
parent_conn = self._acceptConns(parent_conn)
procs.append((proc, parent_conn))
return procs
def _flatten(self, suite):
"""
Flatten test-suite into list of IDs, AND record all test case
into self.cases
CAVEAT: Due to current limitation of the MP plugin, examine the suite
tests to find out if they have class or module fixtures and
group them that way into name of test classes or module.
This is aid in their dispatch.
"""
log.debug("Flattening test into list of IDs")
mods = {}
classes = {}
stack = [suite]
while stack:
suite = stack.pop()
for test in suite:
if isinstance(test, unittest.TestSuite):
stack.append(test)
else:
testid = util.test_name(test)
self.cases[testid] = test
if util.has_module_fixtures(test):
mods.setdefault(test.__class__.__module__, []).append(testid)
elif util.has_class_fixtures(test):
# testclasses support
if test.__class__.__name__ == "_MethodTestCase":
test = test.obj
classes.setdefault(
"%s.%s"
% (test.__class__.__module__, test.__class__.__name__),
[],
).append(testid)
else:
yield testid
for cls in sorted(classes.keys()):
yield cls
for mod in sorted(mods.keys()):
yield mod
def _localize(self, event):
# XXX set loader, case, result etc to local ones, if present in event
# (event case will be just the id)
# (traceback in exc_info if any won't be real!)
if hasattr(event, "result"):
event.result = self.session.testResult
if hasattr(event, "loader"):
event.loader = self.session.testLoader
if hasattr(event, "runner"):
event.runner = self.session.testRunner
if hasattr(event, "test") and isinstance(event.test, six.string_types):
# remote event.case is the test id
try:
event.test = self.cases[event.test]
except KeyError:
# this happens when _flatten augments the test suite
# due to a class or module fixture being present
event.test = self.session.testLoader.loadTestsFromName(
event.test
)._tests[0]
# subtest support
if "subtest" in event.metadata:
message, params = event.metadata.pop("subtest")
# XXX the sentinel value does not survive the pickle
# round-trip and must be reset by hand
if type(message) == type(object()): # noqa: E721
message = unittest.case._subtest_msg_sentinel
event.test = unittest.case._SubTest(event.test, message, params)
def _exportSession(self):
"""
Generate the session information passed to work process.
CAVEAT: The entire contents of which *MUST* be pickeable
and safe to use in the subprocess.
This probably includes:
* No argparse namespaces/named-tuples
* No plugin instances
* No hokes
:return:
"""
export = {
"config": self.session.config,
"verbosity": self.session.verbosity,
"startDir": self.session.startDir,
"topLevelDir": self.session.topLevelDir,
"logLevel": self.session.logLevel,
"pluginClasses": [],
}
event = RegisterInSubprocessEvent()
# fire registerInSubprocess on plugins -- add those plugin classes
# CAVEAT: classes must be pickleable!
self.session.hooks.registerInSubprocess(event)
export["pluginClasses"].extend(event.pluginClasses)
return export
def procserver(session_export, conn):
# init logging system
rlog = multiprocessing.log_to_stderr()
rlog.setLevel(session_export["logLevel"])
# make a real session from the "session" we got
ssn = import_session(rlog, session_export)
if isinstance(conn, Sequence):
conn = connection.Client(conn[:2], authkey=conn[2])
event = SubprocessEvent(
ssn.testLoader, ssn.testResult, ssn.testRunner, ssn.plugins, conn
)
res = ssn.hooks.startSubprocess(event)
if event.handled and not res:
conn.send(None)
conn.close()
ssn.hooks.stopSubprocess(event)
return
# receive and run tests
executor = event.executeTests
for testid in gentests(conn):
if testid is None:
break
# XXX to handle weird cases like layers, need to
# deal with the case that testid is something other
# than a simple string.
test = event.loader.loadTestsFromName(testid)
# XXX If there a need to protect the loop? try/except?
rlog.debug("Execute test %s (%s)", testid, test)
executor(test, event.result)
events = [e for e in ssn.hooks.flush()]
try:
conn.send((testid, events))
rlog.debug("Log for %s returned", testid)
except Exception:
rlog.exception("Fail sending event %s: %s" % (testid, events))
# Send empty event list to unblock the conn.recv on main process.
conn.send((testid, []))
conn.send(None)
conn.close()
ssn.hooks.stopSubprocess(event)
def import_session(rlog, session_export):
ssn = session.Session()
ssn.config = session_export["config"]
ssn.hooks = RecordingPluginInterface()
ssn.verbosity = session_export["verbosity"]
ssn.startDir = session_export["startDir"]
ssn.topLevelDir = session_export["topLevelDir"]
ssn.prepareSysPath()
loader_ = loader.PluggableTestLoader(ssn)
ssn.testLoader = loader_
result_ = result.PluggableTestResult(ssn)
ssn.testResult = result_
runner_ = runner.PluggableTestRunner(ssn) # needed??
ssn.testRunner = runner_
# load and register plugins, forcing multiprocess to the end
ssn.plugins = [
plugin(session=ssn)
for plugin in session_export["pluginClasses"]
if plugin is not MultiProcess
]
rlog.debug("Plugins loaded: %s", ssn.plugins)
for plugin in ssn.plugins:
plugin.register()
rlog.debug("Registered %s in subprocess", plugin)
# instantiating the plugin will register it.
ssn.plugins.append(MultiProcess(session=ssn))
rlog.debug("Registered %s in subprocess", MultiProcess)
ssn.plugins[-1].pluginsLoaded(events.PluginsLoadedEvent(ssn.plugins))
return ssn
# test generator
def gentests(conn):
while True:
try:
testid = conn.recv()
if testid is None:
return
yield testid
except EOFError:
return
# custom event classes
[docs]class SubprocessEvent(events.Event):
"""Event fired at start and end of subprocess execution.
.. attribute :: loader
Test loader instance
.. attribute :: result
Test result
.. attribute :: plugins
List of plugins loaded in the subprocess.
.. attribute :: connection
The :class:`multiprocessing.Connection` instance that the
subprocess uses for communication with the main process.
.. attribute :: executeTests
Callable that will be used to execute tests. Plugins may set
this attribute to wrap or otherwise change test execution. The
callable must match the signature::
def execute(suite, result):
...
"""
def __init__(self, loader, result, runner, plugins, connection, **metadata):
self.loader = loader
self.result = result
self.runner = runner
self.plugins = plugins
self.connection = connection
self.executeTests = lambda test, result: test(result)
super(SubprocessEvent, self).__init__(**metadata)
[docs]class RegisterInSubprocessEvent(events.Event):
"""Event fired to notify plugins that multiprocess testing will occur
.. attribute :: pluginClasses
Add a plugin class to this list to cause the plugin to be
instantiated in each test-running subprocess. The most common
thing to do, for plugins that need to run in subprocesses, is::
def registerInSubprocess(self, event):
event.pluginClasses.append(self.__class__)
"""
def __init__(self, **metadata):
self.pluginClasses = []
super(RegisterInSubprocessEvent, self).__init__(**metadata)
# custom hook system that records calls and events
class RecordingHook(events.Hook):
def __init__(self, method, interface):
super(RecordingHook, self).__init__(method)
self.interface = interface
def __call__(self, event):
res = super(RecordingHook, self).__call__(event)
self.interface.log(self.method, event)
return res
class RecordingPluginInterface(events.PluginInterface):
hookClass = RecordingHook
noLogMethods = set(
[
"getTestCaseNames",
"startSubprocess",
"stopSubprocess",
"registerInSubprocess",
"moduleLoadedSuite",
"getTestMethodNames",
]
)
def __init__(self):
super(RecordingPluginInterface, self).__init__()
self.events = []
def log(self, method, event):
self.events.append((method, event))
def flush(self):
events = self.events[:]
self.events = []
return events
def register(self, method, plugin):
"""Register a plugin for a method.
:param method: A method name
:param plugin: A plugin instance
"""
self._hookForMethod(method).append(plugin)
def __getattr__(self, attr):
if attr.startswith("__"):
raise AttributeError("No %s in %s" % (attr, self))
return self._hookForMethod(attr)
def _hookForMethod(self, method):
# return recording hook for most hooks, normal hook for those
# (like test loading and subprocess events) that we don't want
# to send back to the main process.
try:
return self.hooks[method]
except KeyError:
if method in self.noLogMethods or method.startswith("loadTest"):
hook = events.Hook(method)
else:
hook = self.hookClass(method, self)
self.hooks[method] = hook
return hook