path: root/oslo_concurrency/tests/unit/test_processutils.py

# Copyright 2011 OpenStack Foundation.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

from __future__ import print_function

import errno
import io
import logging
import multiprocessing
import os
import pickle
import resource
import socket
import stat
import subprocess
import sys
import tempfile
from unittest import mock

import fixtures
from oslotest import base as test_base

from oslo_concurrency import processutils


PROCESS_EXECUTION_ERROR_LOGGING_TEST = """#!/bin/bash
exit 41"""

TEST_EXCEPTION_AND_MASKING_SCRIPT = """#!/bin/bash
# This is to test stdout and stderr
# and the command returned in an exception
# when a non-zero exit code is returned
echo onstdout --password='"secret"'
echo onstderr --password='"secret"' 1>&2
exit 38"""

# This byte sequence is undecodable from most encoding
UNDECODABLE_BYTES = b'[a\x80\xe9\xff]'

TRUE_UTILITY = (sys.platform.startswith('darwin') and
                '/usr/bin/true' or '/bin/true')


class UtilsTest(test_base.BaseTestCase):
    # NOTE(jkoelker) Moar tests from nova need to be ported. But they
    #                need to be mock'd out. Currently they require actually
    #                running code.
    def test_execute_unknown_kwargs(self):
        self.assertRaises(processutils.UnknownArgumentError,
                          processutils.execute,
                          hozer=True)

    @mock.patch.object(multiprocessing, 'cpu_count', return_value=8)
    def test_get_worker_count(self, mock_cpu_count):
        self.assertEqual(8, processutils.get_worker_count())

    @mock.patch.object(multiprocessing, 'cpu_count',
                       side_effect=NotImplementedError())
    def test_get_worker_count_cpu_count_not_implemented(self,
                                                        mock_cpu_count):
        self.assertEqual(1, processutils.get_worker_count())

    def test_execute_with_callback(self):
        on_execute_callback = mock.Mock()
        on_completion_callback = mock.Mock()
        processutils.execute(TRUE_UTILITY)
        self.assertEqual(0, on_execute_callback.call_count)
        self.assertEqual(0, on_completion_callback.call_count)

        processutils.execute(TRUE_UTILITY, on_execute=on_execute_callback,
                             on_completion=on_completion_callback)
        self.assertEqual(1, on_execute_callback.call_count)
        self.assertEqual(1, on_completion_callback.call_count)

    @mock.patch.object(subprocess.Popen, "communicate")
    def test_execute_with_callback_and_errors(self, mock_comm):
        on_execute_callback = mock.Mock()
        on_completion_callback = mock.Mock()

        def fake_communicate(*args):
            raise IOError("Broken pipe")

        mock_comm.side_effect = fake_communicate

        self.assertRaises(IOError,
                          processutils.execute,
                          TRUE_UTILITY,
                          on_execute=on_execute_callback,
                          on_completion=on_completion_callback)
        self.assertEqual(1, on_execute_callback.call_count)
        self.assertEqual(1, on_completion_callback.call_count)

    def test_execute_with_preexec_fn(self):
        # NOTE(dims): preexec_fn is set to a callable object, this object
        # will be called in the child process just before the child is
        # executed. So we cannot pass share variables etc, simplest is to
        # check if a specific exception is thrown which can be caught here.
        def preexec_fn():
            raise processutils.InvalidArgumentError()

        processutils.execute(TRUE_UTILITY)

        try:
            processutils.execute(TRUE_UTILITY, preexec_fn=preexec_fn)
        except Exception as e:
            if type(e).__name__ != 'SubprocessError':
                raise

    @mock.patch.object(os, 'name', 'nt')
    @mock.patch.object(processutils.subprocess, "Popen")
    @mock.patch.object(processutils, 'tpool', create=True)
    def _test_windows_execute(self, mock_tpool, mock_popen,
                              use_eventlet=False):
        # We want to ensure that if eventlet is used on Windows,
        # 'communicate' calls are wrapped with eventlet.tpool.execute.
        mock_comm = mock_popen.return_value.communicate
        mock_comm.return_value = None
        mock_tpool.execute.return_value = mock_comm.return_value

        fake_pinput = 'fake pinput'.encode('utf-8')

        with mock.patch.object(processutils, 'eventlet_patched',
                               use_eventlet):
            processutils.execute(
                TRUE_UTILITY,
                process_input=fake_pinput,
                check_exit_code=False)

        mock_popen.assert_called_once_with(
            [TRUE_UTILITY],
            stdin=mock.ANY, stdout=mock.ANY,
            stderr=mock.ANY, close_fds=mock.ANY,
            preexec_fn=mock.ANY, shell=mock.ANY,
            cwd=mock.ANY, env=mock.ANY)

        if use_eventlet:
            mock_tpool.execute.assert_called_once_with(
                mock_comm, fake_pinput)
        else:
            mock_comm.assert_called_once_with(fake_pinput)

    def test_windows_execute_without_eventlet(self):
        self._test_windows_execute()

    def test_windows_execute_using_eventlet(self):
        self._test_windows_execute(use_eventlet=True)


class ProcessExecutionErrorTest(test_base.BaseTestCase):

    def test_defaults(self):
        err = processutils.ProcessExecutionError()
        self.assertIn('None\n', str(err))
        self.assertIn('code: -\n', str(err))

    def test_with_description(self):
        description = 'The Narwhal Bacons at Midnight'
        err = processutils.ProcessExecutionError(description=description)
        self.assertIn(description, str(err))

    def test_with_exit_code(self):
        exit_code = 0
        err = processutils.ProcessExecutionError(exit_code=exit_code)
        self.assertIn(str(exit_code), str(err))

    def test_with_cmd(self):
        cmd = 'telinit'
        err = processutils.ProcessExecutionError(cmd=cmd)
        self.assertIn(cmd, str(err))

    def test_with_stdout(self):
        stdout = """
        Lo, praise of the prowess of people-kings
        of spear-armed Danes, in days long sped,
        we have heard, and what honor the athelings won!
        Oft Scyld the Scefing from squadroned foes,
        from many a tribe, the mead-bench tore,
        awing the earls. Since erst he lay
        friendless, a foundling, fate repaid him:
        for he waxed under welkin, in wealth he throve,
        till before him the folk, both far and near,
        who house by the whale-path, heard his mandate,
        gave him gifts: a good king he!
        To him an heir was afterward born,
        a son in his halls, whom heaven sent
        to favor the folk, feeling their woe
        that erst they had lacked an earl for leader
        so long a while; the Lord endowed him,
        the Wielder of Wonder, with world's renown.
        """.strip()
        err = processutils.ProcessExecutionError(stdout=stdout)
        print(str(err))
        self.assertIn('people-kings', str(err))

    def test_with_stderr(self):
        stderr = 'Cottonian library'
        err = processutils.ProcessExecutionError(stderr=stderr)
        self.assertIn(stderr, str(err))

    def test_retry_on_failure(self):
        fd, tmpfilename = tempfile.mkstemp()
        _, tmpfilename2 = tempfile.mkstemp()
        try:
            fp = os.fdopen(fd, 'w+')
            fp.write('''#!/bin/sh
# If stdin fails to get passed during one of the runs, make a note.
if ! grep -q foo
then
    echo 'failure' > "$1"
fi
# If stdin has failed to get passed during this or a previous run, exit early.
if grep failure "$1"
then
    exit 1
fi
runs="$(cat $1)"
if [ -z "$runs" ]
then
    runs=0
fi
runs=$(($runs + 1))
echo $runs > "$1"
exit 1
''')
            fp.close()
            os.chmod(tmpfilename, 0o755)
            self.assertRaises(processutils.ProcessExecutionError,
                              processutils.execute,
                              tmpfilename, tmpfilename2, attempts=10,
                              process_input=b'foo',
                              delay_on_retry=False)
            fp = open(tmpfilename2, 'r')
            runs = fp.read()
            fp.close()
            self.assertNotEqual('failure', 'stdin did not '
                                           'always get passed '
                                           'correctly',
                                runs.strip())
            runs = int(runs.strip())
            self.assertEqual(10, runs, 'Ran %d times instead of 10.' % (runs,))
        finally:
            os.unlink(tmpfilename)
            os.unlink(tmpfilename2)

    def test_unknown_kwargs_raises_error(self):
        self.assertRaises(processutils.UnknownArgumentError,
                          processutils.execute,
                          '/usr/bin/env', 'true',
                          this_is_not_a_valid_kwarg=True)

    def test_check_exit_code_boolean(self):
        processutils.execute('/usr/bin/env', 'false', check_exit_code=False)
        self.assertRaises(processutils.ProcessExecutionError,
                          processutils.execute,
                          '/usr/bin/env', 'false', check_exit_code=True)

    def test_check_cwd(self):
        tmpdir = tempfile.mkdtemp()
        out, err = processutils.execute('/usr/bin/env',
                                        'sh', '-c', 'pwd',
                                        cwd=tmpdir)
        self.assertIn(tmpdir, out)

    def test_process_input_with_string(self):
        code = ';'.join(('import sys',
                         'print(len(sys.stdin.readlines()))'))
        args = [sys.executable, '-c', code]
        input = "\n".join(['foo', 'bar', 'baz'])
        stdout, stderr = processutils.execute(*args, process_input=input)
        self.assertEqual("3", stdout.rstrip())

    def test_check_exit_code_list(self):
        processutils.execute('/usr/bin/env', 'sh', '-c', 'exit 101',
                             check_exit_code=(101, 102))
        processutils.execute('/usr/bin/env', 'sh', '-c', 'exit 102',
                             check_exit_code=(101, 102))
        self.assertRaises(processutils.ProcessExecutionError,
                          processutils.execute,
                          '/usr/bin/env', 'sh', '-c', 'exit 103',
                          check_exit_code=(101, 102))
        self.assertRaises(processutils.ProcessExecutionError,
                          processutils.execute,
                          '/usr/bin/env', 'sh', '-c', 'exit 0',
                          check_exit_code=(101, 102))

    def test_no_retry_on_success(self):
        fd, tmpfilename = tempfile.mkstemp()
        _, tmpfilename2 = tempfile.mkstemp()
        try:
            fp = os.fdopen(fd, 'w+')
            fp.write("""#!/bin/sh
# If we've already run, bail out.
grep -q foo "$1" && exit 1
# Mark that we've run before.
echo foo > "$1"
# Check that stdin gets passed correctly.
grep foo
""")
            fp.close()
            os.chmod(tmpfilename, 0o755)
            processutils.execute(tmpfilename,
                                 tmpfilename2,
                                 process_input=b'foo',
                                 attempts=2)
        finally:
            os.unlink(tmpfilename)
            os.unlink(tmpfilename2)

    # This test and the one below ensures that when communicate raises
    # an OSError, we do the right thing(s)
    def test_exception_on_communicate_error(self):
        mock = self.useFixture(fixtures.MockPatch(
            'subprocess.Popen.communicate',
            side_effect=OSError(errno.EAGAIN, 'fake-test')))

        self.assertRaises(OSError,
                          processutils.execute,
                          '/usr/bin/env',
                          'false',
                          check_exit_code=False)

        self.assertEqual(1, mock.mock.call_count)

    def test_retry_on_communicate_error(self):
        mock = self.useFixture(fixtures.MockPatch(
            'subprocess.Popen.communicate',
            side_effect=OSError(errno.EAGAIN, 'fake-test')))

        self.assertRaises(OSError,
                          processutils.execute,
                          '/usr/bin/env',
                          'false',
                          check_exit_code=False,
                          attempts=5)

        self.assertEqual(5, mock.mock.call_count)

    def _test_and_check_logging_communicate_errors(self, log_errors=None,
                                                   attempts=None):
        mock = self.useFixture(fixtures.MockPatch(
            'subprocess.Popen.communicate',
            side_effect=OSError(errno.EAGAIN, 'fake-test')))

        fixture = self.useFixture(fixtures.FakeLogger(level=logging.DEBUG))
        kwargs = {}

        if log_errors:
            kwargs.update({"log_errors": log_errors})

        if attempts:
            kwargs.update({"attempts": attempts})

        self.assertRaises(OSError,
                          processutils.execute,
                          '/usr/bin/env',
                          'false',
                          **kwargs)

        self.assertEqual(attempts if attempts else 1, mock.mock.call_count)
        self.assertIn('Got an OSError', fixture.output)
        self.assertIn('errno: %d' % errno.EAGAIN, fixture.output)
        self.assertIn("'/usr/bin/env false'", fixture.output)

    def test_logging_on_communicate_error_1(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_FINAL_ERROR,
            attempts=None)

    def test_logging_on_communicate_error_2(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_FINAL_ERROR,
            attempts=1)

    def test_logging_on_communicate_error_3(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_FINAL_ERROR,
            attempts=5)

    def test_logging_on_communicate_error_4(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_ALL_ERRORS,
            attempts=None)

    def test_logging_on_communicate_error_5(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_ALL_ERRORS,
            attempts=1)

    def test_logging_on_communicate_error_6(self):
        self._test_and_check_logging_communicate_errors(
            log_errors=processutils.LOG_ALL_ERRORS,
            attempts=5)

    def test_with_env_variables(self):
        env_vars = {'SUPER_UNIQUE_VAR': 'The answer is 42'}

        out, err = processutils.execute('/usr/bin/env', env_variables=env_vars)
        self.assertIsInstance(out, str)
        self.assertIsInstance(err, str)

        self.assertIn('SUPER_UNIQUE_VAR=The answer is 42', out)

    def test_binary(self):
        env_vars = {'SUPER_UNIQUE_VAR': 'The answer is 42'}

        out, err = processutils.execute('/usr/bin/env',
                                        env_variables=env_vars,
                                        binary=True)
        self.assertIsInstance(out, bytes)
        self.assertIsInstance(err, bytes)

        self.assertIn(b'SUPER_UNIQUE_VAR=The answer is 42', out)

    def test_exception_and_masking(self):
        tmpfilename = self.create_tempfiles(
            [["test_exceptions_and_masking",
              TEST_EXCEPTION_AND_MASKING_SCRIPT]], ext='bash')[0]

        os.chmod(tmpfilename, (stat.S_IRWXU |
                               stat.S_IRGRP |
                               stat.S_IXGRP |
                               stat.S_IROTH |
                               stat.S_IXOTH))

        err = self.assertRaises(processutils.ProcessExecutionError,
                                processutils.execute,
                                tmpfilename, 'password="secret"',
                                'something')

        self.assertEqual(38, err.exit_code)
        self.assertIsInstance(err.stdout, str)
        self.assertIsInstance(err.stderr, str)
        self.assertIn('onstdout --password="***"', err.stdout)
        self.assertIn('onstderr --password="***"', err.stderr)
        self.assertEqual(' '.join([tmpfilename,
                                   'password="***"',
                                   'something']),
                         err.cmd)
        self.assertNotIn('secret', str(err))

    def execute_undecodable_bytes(self, out_bytes, err_bytes,
                                  exitcode=0, binary=False):
        code = ';'.join(('import sys',
                         'sys.stdout.buffer.write(%a)' % out_bytes,
                         'sys.stdout.flush()',
                         'sys.stderr.buffer.write(%a)' % err_bytes,
                         'sys.stderr.flush()',
                         'sys.exit(%s)' % exitcode))

        return processutils.execute(sys.executable, '-c', code, binary=binary)

    def check_undecodable_bytes(self, binary):
        out_bytes = b'out: ' + UNDECODABLE_BYTES
        err_bytes = b'err: ' + UNDECODABLE_BYTES
        out, err = self.execute_undecodable_bytes(out_bytes, err_bytes,
                                                  binary=binary)
        if not binary:
            self.assertEqual(os.fsdecode(out_bytes), out)
            self.assertEqual(os.fsdecode(err_bytes), err)
        else:
            self.assertEqual(out, out_bytes)
            self.assertEqual(err, err_bytes)

    def test_undecodable_bytes(self):
        self.check_undecodable_bytes(False)

    def test_binary_undecodable_bytes(self):
        self.check_undecodable_bytes(True)

    def check_undecodable_bytes_error(self, binary):
        out_bytes = b'out: password="secret1" ' + UNDECODABLE_BYTES
        err_bytes = b'err: password="secret2" ' + UNDECODABLE_BYTES
        exc = self.assertRaises(processutils.ProcessExecutionError,
                                self.execute_undecodable_bytes,
                                out_bytes, err_bytes, exitcode=1,
                                binary=binary)

        out = exc.stdout
        err = exc.stderr
        out_bytes = b'out: password="***" ' + UNDECODABLE_BYTES
        err_bytes = b'err: password="***" ' + UNDECODABLE_BYTES
        self.assertEqual(os.fsdecode(out_bytes), out)
        self.assertEqual(os.fsdecode(err_bytes), err)

    def test_undecodable_bytes_error(self):
        self.check_undecodable_bytes_error(False)

    def test_binary_undecodable_bytes_error(self):
        self.check_undecodable_bytes_error(True)

    def test_picklable(self):
        exc = processutils.ProcessExecutionError(
            stdout='my stdout', stderr='my stderr',
            exit_code=42, cmd='my cmd',
            description='my description')
        exc_message = str(exc)

        exc = pickle.loads(pickle.dumps(exc))
        self.assertEqual('my stdout', exc.stdout)
        self.assertEqual('my stderr', exc.stderr)
        self.assertEqual(42, exc.exit_code)
        self.assertEqual('my cmd', exc.cmd)
        self.assertEqual('my description', exc.description)
        self.assertEqual(str(exc), exc_message)


class ProcessExecutionErrorLoggingTest(test_base.BaseTestCase):
    def setUp(self):
        super(ProcessExecutionErrorLoggingTest, self).setUp()
        self.tmpfilename = self.create_tempfiles(
            [["process_execution_error_logging_test",
              PROCESS_EXECUTION_ERROR_LOGGING_TEST]],
            ext='bash')[0]

        os.chmod(self.tmpfilename, (stat.S_IRWXU | stat.S_IRGRP |
                                    stat.S_IXGRP | stat.S_IROTH |
                                    stat.S_IXOTH))

    def _test_and_check(self, log_errors=None, attempts=None):
        fixture = self.useFixture(fixtures.FakeLogger(level=logging.DEBUG))
        kwargs = {}

        if log_errors:
            kwargs.update({"log_errors": log_errors})

        if attempts:
            kwargs.update({"attempts": attempts})

        err = self.assertRaises(processutils.ProcessExecutionError,
                                processutils.execute,
                                self.tmpfilename,
                                **kwargs)

        self.assertEqual(41, err.exit_code)
        self.assertIn(self.tmpfilename, fixture.output)

    def test_with_invalid_log_errors(self):
        self.assertRaises(processutils.InvalidArgumentError,
                          processutils.execute,
                          self.tmpfilename,
                          log_errors='invalid')

    def test_with_log_errors_NONE(self):
        self._test_and_check(log_errors=None, attempts=None)

    def test_with_log_errors_final(self):
        self._test_and_check(log_errors=processutils.LOG_FINAL_ERROR,
                             attempts=None)

    def test_with_log_errors_all(self):
        self._test_and_check(log_errors=processutils.LOG_ALL_ERRORS,
                             attempts=None)

    def test_multiattempt_with_log_errors_NONE(self):
        self._test_and_check(log_errors=None, attempts=3)

    def test_multiattempt_with_log_errors_final(self):
        self._test_and_check(log_errors=processutils.LOG_FINAL_ERROR,
                             attempts=3)

    def test_multiattempt_with_log_errors_all(self):
        self._test_and_check(log_errors=processutils.LOG_ALL_ERRORS,
                             attempts=3)


def fake_execute(*cmd, **kwargs):
    return 'stdout', 'stderr'


def fake_execute_raises(*cmd, **kwargs):
    raise processutils.ProcessExecutionError(exit_code=42,
                                             stdout='stdout',
                                             stderr='stderr',
                                             cmd=['this', 'is', 'a',
                                                  'command'])


class TryCmdTestCase(test_base.BaseTestCase):
    def test_keep_warnings(self):
        self.useFixture(fixtures.MonkeyPatch(
            'oslo_concurrency.processutils.execute', fake_execute))
        o, e = processutils.trycmd('this is a command'.split(' '))
        self.assertNotEqual('', o)
        self.assertNotEqual('', e)

    def test_keep_warnings_from_raise(self):
        self.useFixture(fixtures.MonkeyPatch(
            'oslo_concurrency.processutils.execute', fake_execute_raises))
        o, e = processutils.trycmd('this is a command'.split(' '),
                                   discard_warnings=True)
        self.assertIsNotNone(o)
        self.assertNotEqual('', e)

    def test_discard_warnings(self):
        self.useFixture(fixtures.MonkeyPatch(
            'oslo_concurrency.processutils.execute', fake_execute))
        o, e = processutils.trycmd('this is a command'.split(' '),
                                   discard_warnings=True)
        self.assertIsNotNone(o)
        self.assertEqual('', e)


class FakeSshChannel(object):
    def __init__(self, rc):
        self.rc = rc

    def recv_exit_status(self):
        return self.rc


class FakeSshStream(io.BytesIO):
    def setup_channel(self, rc):
        self.channel = FakeSshChannel(rc)


class FakeSshConnection(object):
    def __init__(self, rc, out=b'stdout', err=b'stderr'):
        self.rc = rc
        self.out = out
        self.err = err

    def exec_command(self, cmd, timeout=None):
        if timeout:
            raise socket.timeout()
        stdout = FakeSshStream(self.out)
        stdout.setup_channel(self.rc)
        return (io.BytesIO(),
                stdout,
                io.BytesIO(self.err))


class SshExecuteTestCase(test_base.BaseTestCase):
    def test_invalid_addl_env(self):
        self.assertRaises(processutils.InvalidArgumentError,
                          processutils.ssh_execute,
                          None, 'ls', addl_env='important')

    def test_invalid_process_input(self):
        self.assertRaises(processutils.InvalidArgumentError,
                          processutils.ssh_execute,
                          None, 'ls', process_input='important')

    def test_timeout_error(self):
        self.assertRaises(socket.timeout,
                          processutils.ssh_execute,
                          FakeSshConnection(0), 'ls',
                          timeout=10)

    def test_works(self):
        out, err = processutils.ssh_execute(FakeSshConnection(0), 'ls')
        self.assertEqual('stdout', out)
        self.assertEqual('stderr', err)
        self.assertIsInstance(out, str)
        self.assertIsInstance(err, str)

    def test_binary(self):
        o, e = processutils.ssh_execute(FakeSshConnection(0), 'ls',
                                        binary=True)
        self.assertEqual(b'stdout', o)
        self.assertEqual(b'stderr', e)
        self.assertIsInstance(o, bytes)
        self.assertIsInstance(e, bytes)

    def check_undecodable_bytes(self, binary):
        out_bytes = b'out: ' + UNDECODABLE_BYTES
        err_bytes = b'err: ' + UNDECODABLE_BYTES
        conn = FakeSshConnection(0, out=out_bytes, err=err_bytes)

        out, err = processutils.ssh_execute(conn, 'ls', binary=binary)
        if not binary:
            self.assertEqual(os.fsdecode(out_bytes), out)
            self.assertEqual(os.fsdecode(err_bytes), err)
        else:
            self.assertEqual(out_bytes, out)
            self.assertEqual(err_bytes, err)

    def test_undecodable_bytes(self):
        self.check_undecodable_bytes(False)

    def test_binary_undecodable_bytes(self):
        self.check_undecodable_bytes(True)

    def check_undecodable_bytes_error(self, binary):
        out_bytes = b'out: password="secret1" ' + UNDECODABLE_BYTES
        err_bytes = b'err: password="secret2" ' + UNDECODABLE_BYTES
        conn = FakeSshConnection(1, out=out_bytes, err=err_bytes)

        out_bytes = b'out: password="***" ' + UNDECODABLE_BYTES
        err_bytes = b'err: password="***" ' + UNDECODABLE_BYTES

        exc = self.assertRaises(processutils.ProcessExecutionError,
                                processutils.ssh_execute,
                                conn, 'ls',
                                binary=binary, check_exit_code=True)

        out = exc.stdout
        err = exc.stderr
        self.assertEqual(os.fsdecode(out_bytes), out)
        self.assertEqual(os.fsdecode(err_bytes), err)

    def test_undecodable_bytes_error(self):
        self.check_undecodable_bytes_error(False)

    def test_binary_undecodable_bytes_error(self):
        self.check_undecodable_bytes_error(True)

    def test_fails(self):
        self.assertRaises(processutils.ProcessExecutionError,
                          processutils.ssh_execute, FakeSshConnection(1), 'ls')

    def _test_compromising_ssh(self, rc, check):
        fixture = self.useFixture(fixtures.FakeLogger(level=logging.DEBUG))
        fake_stdin = io.BytesIO()

        fake_stdout = mock.Mock()
        fake_stdout.channel.recv_exit_status.return_value = rc
        fake_stdout.read.return_value = b'password="secret"'

        fake_stderr = mock.Mock()
        fake_stderr.read.return_value = b'password="foobar"'

        command = 'ls --password="bar"'

        connection = mock.Mock()
        connection.exec_command.return_value = (fake_stdin, fake_stdout,
                                                fake_stderr)

        if check and rc != -1 and rc != 0:
            err = self.assertRaises(processutils.ProcessExecutionError,
                                    processutils.ssh_execute,
                                    connection, command,
                                    check_exit_code=check)

            self.assertEqual(rc, err.exit_code)
            self.assertEqual('password="***"', err.stdout)
            self.assertEqual('password="***"', err.stderr)
            self.assertEqual('ls --password="***"', err.cmd)
            self.assertNotIn('secret', str(err))
            self.assertNotIn('foobar', str(err))

            # test ssh_execute with sanitize_stdout=False
            err = self.assertRaises(processutils.ProcessExecutionError,
                                    processutils.ssh_execute,
                                    connection, command,
                                    check_exit_code=check,
                                    sanitize_stdout=False)

            self.assertEqual(rc, err.exit_code)
            self.assertEqual('password="***"', err.stdout)
            self.assertEqual('password="***"', err.stderr)
            self.assertEqual('ls --password="***"', err.cmd)
            self.assertNotIn('secret', str(err))
            self.assertNotIn('foobar', str(err))
        else:
            o, e = processutils.ssh_execute(connection, command,
                                            check_exit_code=check)
            self.assertEqual('password="***"', o)
            self.assertEqual('password="***"', e)
            self.assertIn('password="***"', fixture.output)
            self.assertNotIn('bar', fixture.output)

            # test ssh_execute with sanitize_stdout=False
            o, e = processutils.ssh_execute(connection, command,
                                            check_exit_code=check,
                                            sanitize_stdout=False)
            self.assertEqual('password="secret"', o)
            self.assertEqual('password="***"', e)
            self.assertIn('password="***"', fixture.output)
            self.assertNotIn('bar', fixture.output)

    def test_compromising_ssh1(self):
        self._test_compromising_ssh(rc=-1, check=True)

    def test_compromising_ssh2(self):
        self._test_compromising_ssh(rc=0, check=True)

    def test_compromising_ssh3(self):
        self._test_compromising_ssh(rc=1, check=True)

    def test_compromising_ssh4(self):
        self._test_compromising_ssh(rc=1, check=False)

    def test_compromising_ssh5(self):
        self._test_compromising_ssh(rc=0, check=False)

    def test_compromising_ssh6(self):
        self._test_compromising_ssh(rc=-1, check=False)


class PrlimitTestCase(test_base.BaseTestCase):
    # Simply program that does nothing and returns an exit code 0.
    # Use Python to be portable.
    SIMPLE_PROGRAM = [sys.executable, '-c', 'pass']

    def soft_limit(self, res, substract, default_limit):
        # Create a new soft limit for a resource, lower than the current
        # soft limit.
        soft_limit, hard_limit = resource.getrlimit(res)
        if soft_limit <= 0:
            soft_limit = default_limit
        else:
            soft_limit -= substract
        return soft_limit

    def memory_limit(self, res):
        # Substract 1 kB just to get a different limit. Don't substract too
        # much to avoid memory allocation issues.
        #
        # Use 1 GB by default. Limit high enough to be able to load shared
        # libraries. Limit low enough to be work on 32-bit platforms.
        return self.soft_limit(res, 1024, 1024 ** 3)

    def limit_address_space(self):
        max_memory = self.memory_limit(resource.RLIMIT_AS)
        return processutils.ProcessLimits(address_space=max_memory)

    def test_simple(self):
        # Simple test running a program (/bin/true) with no parameter
        prlimit = self.limit_address_space()
        stdout, stderr = processutils.execute(*self.SIMPLE_PROGRAM,
                                              prlimit=prlimit)
        self.assertEqual('', stdout.rstrip())
        self.assertEqual(stderr.rstrip(), '')

    def check_limit(self, prlimit, resource, value):
        code = ';'.join(('import resource',
                         'print(resource.getrlimit(resource.%s))' % resource))
        args = [sys.executable, '-c', code]
        stdout, stderr = processutils.execute(*args, prlimit=prlimit)
        expected = (value, value)
        self.assertEqual(str(expected), stdout.rstrip())

    def test_address_space(self):
        prlimit = self.limit_address_space()
        self.check_limit(prlimit, 'RLIMIT_AS', prlimit.address_space)

    def test_core_size(self):
        size = self.soft_limit(resource.RLIMIT_CORE, 1, 1024)
        prlimit = processutils.ProcessLimits(core_file_size=size)
        self.check_limit(prlimit, 'RLIMIT_CORE', prlimit.core_file_size)

    def test_cpu_time(self):
        time = self.soft_limit(resource.RLIMIT_CPU, 1, 1024)
        prlimit = processutils.ProcessLimits(cpu_time=time)
        self.check_limit(prlimit, 'RLIMIT_CPU', prlimit.cpu_time)

    def test_data_size(self):
        max_memory = self.memory_limit(resource.RLIMIT_DATA)
        prlimit = processutils.ProcessLimits(data_size=max_memory)
        self.check_limit(prlimit, 'RLIMIT_DATA', max_memory)

    def test_file_size(self):
        size = self.soft_limit(resource.RLIMIT_FSIZE, 1, 1024)
        prlimit = processutils.ProcessLimits(file_size=size)
        self.check_limit(prlimit, 'RLIMIT_FSIZE', prlimit.file_size)

    def test_memory_locked(self):
        max_memory = self.memory_limit(resource.RLIMIT_MEMLOCK)
        prlimit = processutils.ProcessLimits(memory_locked=max_memory)
        self.check_limit(prlimit, 'RLIMIT_MEMLOCK', max_memory)

    def test_resident_set_size(self):
        max_memory = self.memory_limit(resource.RLIMIT_RSS)
        prlimit = processutils.ProcessLimits(resident_set_size=max_memory)
        self.check_limit(prlimit, 'RLIMIT_RSS', max_memory)

    def test_number_files(self):
        nfiles = self.soft_limit(resource.RLIMIT_NOFILE, 1, 1024)
        prlimit = processutils.ProcessLimits(number_files=nfiles)
        self.check_limit(prlimit, 'RLIMIT_NOFILE', nfiles)

    def test_number_processes(self):
        nprocs = self.soft_limit(resource.RLIMIT_NPROC, 1, 65535)
        prlimit = processutils.ProcessLimits(number_processes=nprocs)
        self.check_limit(prlimit, 'RLIMIT_NPROC', nprocs)

    def test_stack_size(self):
        max_memory = self.memory_limit(resource.RLIMIT_STACK)
        prlimit = processutils.ProcessLimits(stack_size=max_memory)
        self.check_limit(prlimit, 'RLIMIT_STACK', max_memory)

    def test_unsupported_prlimit(self):
        self.assertRaises(ValueError, processutils.ProcessLimits, xxx=33)

    def test_relative_path(self):
        prlimit = self.limit_address_space()
        program = sys.executable

        env = dict(os.environ)
        env['PATH'] = os.path.dirname(program)
        args = [os.path.basename(program), '-c', 'pass']
        processutils.execute(*args, prlimit=prlimit, env_variables=env)

    def test_execv_error(self):
        prlimit = self.limit_address_space()
        args = ['/missing_path/dont_exist/program']
        try:
            processutils.execute(*args, prlimit=prlimit)
        except processutils.ProcessExecutionError as exc:
            self.assertEqual(1, exc.exit_code)
            self.assertEqual('', exc.stdout)
            expected = ('%s -m oslo_concurrency.prlimit: '
                        'failed to execute /missing_path/dont_exist/program: '
                        % os.path.basename(sys.executable))
            self.assertIn(expected, exc.stderr)
        else:
            self.fail("ProcessExecutionError not raised")

    def test_setrlimit_error(self):
        prlimit = self.limit_address_space()

        # trying to set a limit higher than the current hard limit
        # with setrlimit() should fail.
        higher_limit = prlimit.address_space + 1024

        args = [sys.executable, '-m', 'oslo_concurrency.prlimit',
                '--as=%s' % higher_limit,
                '--']
        args.extend(self.SIMPLE_PROGRAM)
        try:
            processutils.execute(*args, prlimit=prlimit)
        except processutils.ProcessExecutionError as exc:
            self.assertEqual(1, exc.exit_code)
            self.assertEqual('', exc.stdout)
            expected = ('%s -m oslo_concurrency.prlimit: '
                        'failed to set the AS resource limit: '
                        % os.path.basename(sys.executable))
            self.assertIn(expected, exc.stderr)
        else:
            self.fail("ProcessExecutionError not raised")

    @mock.patch.object(os, 'name', 'nt')
    @mock.patch.object(processutils.subprocess, "Popen")
    def test_prlimit_windows(self, mock_popen):
        # We want to ensure that process resource limits are
        # ignored on Windows, in which case this feature is not
        # supported. We'll just check the command passed to Popen,
        # which is expected to be unaltered.
        prlimit = self.limit_address_space()
        mock_popen.return_value.communicate.return_value = None

        processutils.execute(
            *self.SIMPLE_PROGRAM,
            prlimit=prlimit,
            check_exit_code=False)

        mock_popen.assert_called_once_with(
            self.SIMPLE_PROGRAM,
            stdin=mock.ANY, stdout=mock.ANY,
            stderr=mock.ANY, close_fds=mock.ANY,
            preexec_fn=mock.ANY, shell=mock.ANY,
            cwd=mock.ANY, env=mock.ANY)

    @mock.patch.object(processutils.subprocess, 'Popen')
    def test_python_exec(self, sub_mock):
        mock_subprocess = mock.MagicMock()
        mock_subprocess.communicate.return_value = (b'', b'')
        sub_mock.return_value = mock_subprocess
        args = ['/a/command']
        prlimit = self.limit_address_space()

        processutils.execute(*args, prlimit=prlimit, check_exit_code=False,
                             python_exec='/fake_path')
        python_path = sub_mock.mock_calls[0][1][0][0]
        self.assertEqual('/fake_path', python_path)