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# Copyright (c) 2008-2010 Twisted Matrix Laboratories.
# See LICENSE for details.
"""
Tests for implementations of L{IReactorProcess}.
"""
__metaclass__ = type
import os, sys, signal, threading
from twisted.trial.unittest import TestCase, SkipTest
from twisted.internet.test.reactormixins import ReactorBuilder
from twisted.python.compat import set
from twisted.python.log import msg, err
from twisted.python.runtime import platform
from twisted.python.filepath import FilePath
from twisted.internet import utils
from twisted.internet.interfaces import IReactorProcess
from twisted.internet.defer import Deferred, succeed
from twisted.internet.protocol import ProcessProtocol
from twisted.internet.error import ProcessDone, ProcessTerminated
class _ShutdownCallbackProcessProtocol(ProcessProtocol):
"""
An L{IProcessProtocol} which fires a Deferred when the process it is
associated with ends.
"""
def __init__(self, whenFinished):
self.whenFinished = whenFinished
def processEnded(self, reason):
self.whenFinished.callback(None)
class ProcessTestsBuilderBase(ReactorBuilder):
"""
Base class for L{IReactorProcess} tests which defines some tests which
can be applied to PTY or non-PTY uses of C{spawnProcess}.
Subclasses are expected to set the C{usePTY} attribute to C{True} or
C{False}.
"""
requiredInterfaces = [IReactorProcess]
def test_spawnProcessEarlyIsReaped(self):
"""
If, before the reactor is started with L{IReactorCore.run}, a
process is started with L{IReactorProcess.spawnProcess} and
terminates, the process is reaped once the reactor is started.
"""
reactor = self.buildReactor()
# Create the process with no shared file descriptors, so that there
# are no other events for the reactor to notice and "cheat" with.
# We want to be sure it's really dealing with the process exiting,
# not some associated event.
if self.usePTY:
childFDs = None
else:
childFDs = {}
# Arrange to notice the SIGCHLD.
signaled = threading.Event()
def handler(*args):
signaled.set()
signal.signal(signal.SIGCHLD, handler)
# Start a process - before starting the reactor!
ended = Deferred()
reactor.spawnProcess(
_ShutdownCallbackProcessProtocol(ended), sys.executable,
[sys.executable, "-c", ""], usePTY=self.usePTY, childFDs=childFDs)
# Wait for the SIGCHLD (which might have been delivered before we got
# here, but that's okay because the signal handler was installed above,
# before we could have gotten it).
signaled.wait(120)
if not signaled.isSet():
self.fail("Timed out waiting for child process to exit.")
# Capture the processEnded callback.
result = []
ended.addCallback(result.append)
if result:
# The synchronous path through spawnProcess / Process.__init__ /
# registerReapProcessHandler was encountered. There's no reason to
# start the reactor, because everything is done already.
return
# Otherwise, though, start the reactor so it can tell us the process
# exited.
ended.addCallback(lambda ignored: reactor.stop())
self.runReactor(reactor)
# Make sure the reactor stopped because the Deferred fired.
self.assertTrue(result)
if getattr(signal, 'SIGCHLD', None) is None:
test_spawnProcessEarlyIsReaped.skip = (
"Platform lacks SIGCHLD, early-spawnProcess test can't work.")
def test_processExitedWithSignal(self):
"""
The C{reason} argument passed to L{IProcessProtocol.processExited} is a
L{ProcessTerminated} instance if the child process exits with a signal.
"""
sigName = 'TERM'
sigNum = getattr(signal, 'SIG' + sigName)
exited = Deferred()
source = (
"import sys\n"
# Talk so the parent process knows the process is running. This is
# necessary because ProcessProtocol.makeConnection may be called
# before this process is exec'd. It would be unfortunate if we
# SIGTERM'd the Twisted process while it was on its way to doing
# the exec.
"sys.stdout.write('x')\n"
"sys.stdout.flush()\n"
"sys.stdin.read()\n")
class Exiter(ProcessProtocol):
def childDataReceived(self, fd, data):
msg('childDataReceived(%d, %r)' % (fd, data))
self.transport.signalProcess(sigName)
def childConnectionLost(self, fd):
msg('childConnectionLost(%d)' % (fd,))
def processExited(self, reason):
msg('processExited(%r)' % (reason,))
# Protect the Deferred from the failure so that it follows
# the callback chain. This doesn't use the errback chain
# because it wants to make sure reason is a Failure. An
# Exception would also make an errback-based test pass, and
# that would be wrong.
exited.callback([reason])
def processEnded(self, reason):
msg('processEnded(%r)' % (reason,))
reactor = self.buildReactor()
reactor.callWhenRunning(
reactor.spawnProcess, Exiter(), sys.executable,
[sys.executable, "-c", source], usePTY=self.usePTY)
def cbExited((failure,)):
# Trapping implicitly verifies that it's a Failure (rather than
# an exception) and explicitly makes sure it's the right type.
failure.trap(ProcessTerminated)
err = failure.value
if platform.isWindows():
# Windows can't really /have/ signals, so it certainly can't
# report them as the reason for termination. Maybe there's
# something better we could be doing here, anyway? Hard to
# say. Anyway, this inconsistency between different platforms
# is extremely unfortunate and I would remove it if I
# could. -exarkun
self.assertIdentical(err.signal, None)
self.assertEqual(err.exitCode, 1)
else:
self.assertEqual(err.signal, sigNum)
self.assertIdentical(err.exitCode, None)
exited.addCallback(cbExited)
exited.addErrback(err)
exited.addCallback(lambda ign: reactor.stop())
self.runReactor(reactor)
def test_systemCallUninterruptedByChildExit(self):
"""
If a child process exits while a system call is in progress, the system
call should not be interfered with. In particular, it should not fail
with EINTR.
Older versions of Twisted installed a SIGCHLD handler on POSIX without
using the feature exposed by the SA_RESTART flag to sigaction(2). The
most noticable problem this caused was for blocking reads and writes to
sometimes fail with EINTR.
"""
reactor = self.buildReactor()
# XXX Since pygobject/pygtk wants to use signal.set_wakeup_fd,
# we aren't actually providing this functionality on the glib2
# or gtk2 reactors yet. See #4286 for the possibility of
# improving this.
skippedReactors = ["Glib2Reactor", "Gtk2Reactor"]
hasSigInterrupt = getattr(signal, "siginterrupt", None) is not None
reactorClassName = reactor.__class__.__name__
if reactorClassName in skippedReactors and not hasSigInterrupt:
raise SkipTest(
"%s is not supported without siginterrupt" % reactorClassName)
result = []
def f():
try:
f1 = os.popen('%s -c "import time; time.sleep(0.1)"' %
(sys.executable,))
f2 = os.popen('%s -c "import time; time.sleep(0.5); print \'Foo\'"' %
(sys.executable,))
# The read call below will blow up with an EINTR from the
# SIGCHLD from the first process exiting if we install a
# SIGCHLD handler without SA_RESTART. (which we used to do)
result.append(f2.read())
finally:
reactor.stop()
reactor.callWhenRunning(f)
self.runReactor(reactor)
self.assertEqual(result, ["Foo\n"])
class ProcessTestsBuilder(ProcessTestsBuilderBase):
"""
Builder defining tests relating to L{IReactorProcess} for child processes
which do not have a PTY.
"""
usePTY = False
keepStdioOpenProgram = FilePath(__file__).sibling('process_helper.py').path
if platform.isWindows():
keepStdioOpenArg = "windows"
else:
# Just a value that doesn't equal "windows"
keepStdioOpenArg = ""
# Define this test here because PTY-using processes only have stdin and
# stdout and the test would need to be different for that to work.
def test_childConnectionLost(self):
"""
L{IProcessProtocol.childConnectionLost} is called each time a file
descriptor associated with a child process is closed.
"""
connected = Deferred()
lost = {0: Deferred(), 1: Deferred(), 2: Deferred()}
class Closer(ProcessProtocol):
def makeConnection(self, transport):
connected.callback(transport)
def childConnectionLost(self, childFD):
lost[childFD].callback(None)
source = (
"import os, sys\n"
"while 1:\n"
" line = sys.stdin.readline().strip()\n"
" if not line:\n"
" break\n"
" os.close(int(line))\n")
reactor = self.buildReactor()
reactor.callWhenRunning(
reactor.spawnProcess, Closer(), sys.executable,
[sys.executable, "-c", source], usePTY=self.usePTY)
def cbConnected(transport):
transport.write('2\n')
return lost[2].addCallback(lambda ign: transport)
connected.addCallback(cbConnected)
def lostSecond(transport):
transport.write('1\n')
return lost[1].addCallback(lambda ign: transport)
connected.addCallback(lostSecond)
def lostFirst(transport):
transport.write('\n')
connected.addCallback(lostFirst)
connected.addErrback(err)
def cbEnded(ignored):
reactor.stop()
connected.addCallback(cbEnded)
self.runReactor(reactor)
# This test is here because PTYProcess never delivers childConnectionLost.
def test_processEnded(self):
"""
L{IProcessProtocol.processEnded} is called after the child process
exits and L{IProcessProtocol.childConnectionLost} is called for each of
its file descriptors.
"""
ended = Deferred()
lost = []
class Ender(ProcessProtocol):
def childDataReceived(self, fd, data):
msg('childDataReceived(%d, %r)' % (fd, data))
self.transport.loseConnection()
def childConnectionLost(self, childFD):
msg('childConnectionLost(%d)' % (childFD,))
lost.append(childFD)
def processExited(self, reason):
msg('processExited(%r)' % (reason,))
def processEnded(self, reason):
msg('processEnded(%r)' % (reason,))
ended.callback([reason])
reactor = self.buildReactor()
reactor.callWhenRunning(
reactor.spawnProcess, Ender(), sys.executable,
[sys.executable, self.keepStdioOpenProgram, "child",
self.keepStdioOpenArg],
usePTY=self.usePTY)
def cbEnded((failure,)):
failure.trap(ProcessDone)
self.assertEqual(set(lost), set([0, 1, 2]))
ended.addCallback(cbEnded)
ended.addErrback(err)
ended.addCallback(lambda ign: reactor.stop())
self.runReactor(reactor)
# This test is here because PTYProcess.loseConnection does not actually
# close the file descriptors to the child process. This test needs to be
# written fairly differently for PTYProcess.
def test_processExited(self):
"""
L{IProcessProtocol.processExited} is called when the child process
exits, even if file descriptors associated with the child are still
open.
"""
exited = Deferred()
allLost = Deferred()
lost = []
class Waiter(ProcessProtocol):
def childDataReceived(self, fd, data):
msg('childDataReceived(%d, %r)' % (fd, data))
def childConnectionLost(self, childFD):
msg('childConnectionLost(%d)' % (childFD,))
lost.append(childFD)
if len(lost) == 3:
allLost.callback(None)
def processExited(self, reason):
msg('processExited(%r)' % (reason,))
# See test_processExitedWithSignal
exited.callback([reason])
self.transport.loseConnection()
reactor = self.buildReactor()
reactor.callWhenRunning(
reactor.spawnProcess, Waiter(), sys.executable,
[sys.executable, self.keepStdioOpenProgram, "child",
self.keepStdioOpenArg],
usePTY=self.usePTY)
def cbExited((failure,)):
failure.trap(ProcessDone)
msg('cbExited; lost = %s' % (lost,))
self.assertEqual(lost, [])
return allLost
exited.addCallback(cbExited)
def cbAllLost(ignored):
self.assertEqual(set(lost), set([0, 1, 2]))
exited.addCallback(cbAllLost)
exited.addErrback(err)
exited.addCallback(lambda ign: reactor.stop())
self.runReactor(reactor)
def makeSourceFile(self, sourceLines):
"""
Write the given list of lines to a text file and return the absolute
path to it.
"""
script = self.mktemp()
scriptFile = file(script, 'wt')
scriptFile.write(os.linesep.join(sourceLines) + os.linesep)
scriptFile.close()
return os.path.abspath(script)
def test_shebang(self):
"""
Spawning a process with an executable which is a script starting
with an interpreter definition line (#!) uses that interpreter to
evaluate the script.
"""
SHEBANG_OUTPUT = 'this is the shebang output'
scriptFile = self.makeSourceFile([
"#!%s" % (sys.executable,),
"import sys",
"sys.stdout.write('%s')" % (SHEBANG_OUTPUT,),
"sys.stdout.flush()"])
os.chmod(scriptFile, 0700)
reactor = self.buildReactor()
def cbProcessExited((out, err, code)):
msg("cbProcessExited((%r, %r, %d))" % (out, err, code))
self.assertEqual(out, SHEBANG_OUTPUT)
self.assertEqual(err, "")
self.assertEqual(code, 0)
def shutdown(passthrough):
reactor.stop()
return passthrough
def start():
d = utils.getProcessOutputAndValue(scriptFile, reactor=reactor)
d.addBoth(shutdown)
d.addCallback(cbProcessExited)
d.addErrback(err)
reactor.callWhenRunning(start)
self.runReactor(reactor)
def test_processCommandLineArguments(self):
"""
Arguments given to spawnProcess are passed to the child process as
originally intended.
"""
source = (
# On Windows, stdout is not opened in binary mode by default,
# so newline characters are munged on writing, interfering with
# the tests.
'import sys, os\n'
'try:\n'
' import msvcrt\n'
' msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)\n'
'except ImportError:\n'
' pass\n'
'for arg in sys.argv[1:]:\n'
' sys.stdout.write(arg + chr(0))\n'
' sys.stdout.flush()')
args = ['hello', '"', ' \t|<>^&', r'"\\"hello\\"', r'"foo\ bar baz\""']
# Ensure that all non-NUL characters can be passed too.
args.append(''.join(map(chr, xrange(1, 256))))
reactor = self.buildReactor()
def processFinished(output):
output = output.split('\0')
# Drop the trailing \0.
output.pop()
self.assertEquals(args, output)
def shutdown(result):
reactor.stop()
return result
def spawnChild():
d = succeed(None)
d.addCallback(lambda dummy: utils.getProcessOutput(
sys.executable, ['-c', source] + args, reactor=reactor))
d.addCallback(processFinished)
d.addBoth(shutdown)
reactor.callWhenRunning(spawnChild)
self.runReactor(reactor)
globals().update(ProcessTestsBuilder.makeTestCaseClasses())
class PTYProcessTestsBuilder(ProcessTestsBuilderBase):
"""
Builder defining tests relating to L{IReactorProcess} for child processes
which have a PTY.
"""
usePTY = True
if platform.isWindows():
skip = "PTYs are not supported on Windows."
elif platform.isMacOSX():
skippedReactors = {
"twisted.internet.pollreactor.PollReactor":
"OS X's poll() does not support PTYs"}
globals().update(PTYProcessTestsBuilder.makeTestCaseClasses())
class PotentialZombieWarningTests(TestCase):
"""
Tests for L{twisted.internet.error.PotentialZombieWarning}.
"""
def test_deprecated(self):
"""
Accessing L{PotentialZombieWarning} via the
I{PotentialZombieWarning} attribute of L{twisted.internet.error}
results in a deprecation warning being emitted.
"""
from twisted.internet import error
error.PotentialZombieWarning
warnings = self.flushWarnings([self.test_deprecated])
self.assertEquals(warnings[0]['category'], DeprecationWarning)
self.assertEquals(
warnings[0]['message'],
"twisted.internet.error.PotentialZombieWarning was deprecated in "
"Twisted 10.0.0: There is no longer any potential for zombie "
"process.")
self.assertEquals(len(warnings), 1)
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