qemu-iotests: add iotests Python module

Block layer tests that involve QMP commands rather than qemu-img or
qemu-io are not well-suited for shell scripting.  This patch adds a
Python module which allows tests to be written in Python instead.

The basic API is:

  VM          - class for launching and interacting with a VM
  QMPTestCase - abstract base class for tests that use QMP
  qemu_img()  - wrapper function for invoking qemu-img
  qemu_io()   - wrapper function for invoking qemu-io
  imgfmt      - the image format under test (e.g. qcow2, qed)
  test_dir    - scratch directory path for temporary files
  main()      - entry point for running tests

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2012-02-29 13:25:21 +00:00 committed by Kevin Wolf
parent 049255b60c
commit f345cfd019

View File

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# Common utilities and Python wrappers for qemu-iotests
#
# Copyright (C) 2012 IBM Corp.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
import os
import re
import subprocess
import unittest
import sys; sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'QMP'))
import qmp
__all__ = ['imgfmt', 'imgproto', 'test_dir' 'qemu_img', 'qemu_io',
'VM', 'QMPTestCase', 'notrun', 'main']
# This will not work if arguments or path contain spaces but is necessary if we
# want to support the override options that ./check supports.
qemu_img_args = os.environ.get('QEMU_IMG', 'qemu-img').split(' ')
qemu_io_args = os.environ.get('QEMU_IO', 'qemu-io').split(' ')
qemu_args = os.environ.get('QEMU', 'qemu').split(' ')
imgfmt = os.environ.get('IMGFMT', 'raw')
imgproto = os.environ.get('IMGPROTO', 'file')
test_dir = os.environ.get('TEST_DIR', '/var/tmp')
def qemu_img(*args):
'''Run qemu-img and return the exit code'''
devnull = open('/dev/null', 'r+')
return subprocess.call(qemu_img_args + list(args), stdin=devnull, stdout=devnull)
def qemu_io(*args):
'''Run qemu-io and return the stdout data'''
args = qemu_io_args + list(args)
return subprocess.Popen(args, stdout=subprocess.PIPE).communicate()[0]
class VM(object):
'''A QEMU VM'''
def __init__(self):
self._monitor_path = os.path.join(test_dir, 'qemu-mon.%d' % os.getpid())
self._qemu_log_path = os.path.join(test_dir, 'qemu-log.%d' % os.getpid())
self._args = qemu_args + ['-chardev',
'socket,id=mon,path=' + self._monitor_path,
'-mon', 'chardev=mon,mode=control', '-nographic']
self._num_drives = 0
def add_drive(self, path, opts=''):
'''Add a virtio-blk drive to the VM'''
options = ['if=virtio',
'format=%s' % imgfmt,
'cache=none',
'file=%s' % path,
'id=drive%d' % self._num_drives]
if opts:
options.append(opts)
self._args.append('-drive')
self._args.append(','.join(options))
self._num_drives += 1
return self
def launch(self):
'''Launch the VM and establish a QMP connection'''
devnull = open('/dev/null', 'rb')
qemulog = open(self._qemu_log_path, 'wb')
try:
self._qmp = qmp.QEMUMonitorProtocol(self._monitor_path, server=True)
self._popen = subprocess.Popen(self._args, stdin=devnull, stdout=qemulog,
stderr=subprocess.STDOUT)
self._qmp.accept()
except:
os.remove(self._monitor_path)
raise
def shutdown(self):
'''Terminate the VM and clean up'''
self._qmp.cmd('quit')
self._popen.wait()
os.remove(self._monitor_path)
os.remove(self._qemu_log_path)
def qmp(self, cmd, **args):
'''Invoke a QMP command and return the result dict'''
return self._qmp.cmd(cmd, args=args)
def get_qmp_events(self, wait=False):
'''Poll for queued QMP events and return a list of dicts'''
events = self._qmp.get_events(wait=wait)
self._qmp.clear_events()
return events
index_re = re.compile(r'([^\[]+)\[([^\]]+)\]')
class QMPTestCase(unittest.TestCase):
'''Abstract base class for QMP test cases'''
def dictpath(self, d, path):
'''Traverse a path in a nested dict'''
for component in path.split('/'):
m = index_re.match(component)
if m:
component, idx = m.groups()
idx = int(idx)
if not isinstance(d, dict) or component not in d:
self.fail('failed path traversal for "%s" in "%s"' % (path, str(d)))
d = d[component]
if m:
if not isinstance(d, list):
self.fail('path component "%s" in "%s" is not a list in "%s"' % (component, path, str(d)))
try:
d = d[idx]
except IndexError:
self.fail('invalid index "%s" in path "%s" in "%s"' % (idx, path, str(d)))
return d
def assert_qmp(self, d, path, value):
'''Assert that the value for a specific path in a QMP dict matches'''
result = self.dictpath(d, path)
self.assertEqual(result, value, 'values not equal "%s" and "%s"' % (str(result), str(value)))
def notrun(reason):
'''Skip this test suite'''
# Each test in qemu-iotests has a number ("seq")
seq = os.path.basename(sys.argv[0])
open('%s.notrun' % seq, 'wb').write(reason + '\n')
print '%s not run: %s' % (seq, reason)
sys.exit(0)
def main(supported_fmts=[]):
'''Run tests'''
if supported_fmts and (imgfmt not in supported_fmts):
notrun('not suitable for this image format: %s' % imgfmt)
# We need to filter out the time taken from the output so that qemu-iotest
# can reliably diff the results against master output.
import StringIO
output = StringIO.StringIO()
class MyTestRunner(unittest.TextTestRunner):
def __init__(self, stream=output, descriptions=True, verbosity=1):
unittest.TextTestRunner.__init__(self, stream, descriptions, verbosity)
# unittest.main() will use sys.exit() so expect a SystemExit exception
try:
unittest.main(testRunner=MyTestRunner)
finally:
sys.stderr.write(re.sub(r'Ran (\d+) test[s] in [\d.]+s', r'Ran \1 tests', output.getvalue()))