qemu/scripts/qmp/qemu-ga-client
John Snow f85d3252ef scripts/qemu-ga-client: apply (most) pylint rules
I'm only doing a very quick best-effort to preserve this script, to help
keep it from breaking further. I think there are pending ideas swirling
on the right way to implement better SDKs and better clients, and this
script might be a handy reference for those discussions. It presents
some interesting design problems, like static type safety when using a
dynamic RPC mechanism.

I believe it's worth preserving the effort and care that went into
making this script by updating it to work with our current
infrastructure. However, I am disabling the requirement for docstrings
in this file.

If you would like to help improve this script, please add docstrings
alongside any refactors or rejuvenations you might apply at that time.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210604155532.1499282-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-18 16:10:06 -04:00

318 lines
8.3 KiB
Python
Executable file

#!/usr/bin/env python3
"""
QEMU Guest Agent Client
Usage:
Start QEMU with:
# qemu [...] -chardev socket,path=/tmp/qga.sock,server,wait=off,id=qga0 \
-device virtio-serial \
-device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0
Run the script:
$ qemu-ga-client --address=/tmp/qga.sock <command> [args...]
or
$ export QGA_CLIENT_ADDRESS=/tmp/qga.sock
$ qemu-ga-client <command> [args...]
For example:
$ qemu-ga-client cat /etc/resolv.conf
# Generated by NetworkManager
nameserver 10.0.2.3
$ qemu-ga-client fsfreeze status
thawed
$ qemu-ga-client fsfreeze freeze
2 filesystems frozen
See also: https://wiki.qemu.org/Features/QAPI/GuestAgent
"""
# Copyright (C) 2012 Ryota Ozaki <ozaki.ryota@gmail.com>
#
# This work is licensed under the terms of the GNU GPL, version 2. See
# the COPYING file in the top-level directory.
import argparse
import base64
import errno
import os
import random
import sys
sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
from qemu import qmp
# This script has not seen many patches or careful attention in quite
# some time. If you would like to improve it, please review the design
# carefully and add docstrings at that point in time. Until then:
# pylint: disable=missing-docstring
class QemuGuestAgent(qmp.QEMUMonitorProtocol):
def __getattr__(self, name):
def wrapper(**kwds):
return self.command('guest-' + name.replace('_', '-'), **kwds)
return wrapper
class QemuGuestAgentClient:
def __init__(self, address):
self.qga = QemuGuestAgent(address)
self.qga.connect(negotiate=False)
def sync(self, timeout=3):
# Avoid being blocked forever
if not self.ping(timeout):
raise EnvironmentError('Agent seems not alive')
uid = random.randint(0, (1 << 32) - 1)
while True:
ret = self.qga.sync(id=uid)
if isinstance(ret, int) and int(ret) == uid:
break
def __file_read_all(self, handle):
eof = False
data = ''
while not eof:
ret = self.qga.file_read(handle=handle, count=1024)
_data = base64.b64decode(ret['buf-b64'])
data += _data
eof = ret['eof']
return data
def read(self, path):
handle = self.qga.file_open(path=path)
try:
data = self.__file_read_all(handle)
finally:
self.qga.file_close(handle=handle)
return data
def info(self):
info = self.qga.info()
msgs = []
msgs.append('version: ' + info['version'])
msgs.append('supported_commands:')
enabled = [c['name'] for c in info['supported_commands']
if c['enabled']]
msgs.append('\tenabled: ' + ', '.join(enabled))
disabled = [c['name'] for c in info['supported_commands']
if not c['enabled']]
msgs.append('\tdisabled: ' + ', '.join(disabled))
return '\n'.join(msgs)
@classmethod
def __gen_ipv4_netmask(cls, prefixlen):
mask = int('1' * prefixlen + '0' * (32 - prefixlen), 2)
return '.'.join([str(mask >> 24),
str((mask >> 16) & 0xff),
str((mask >> 8) & 0xff),
str(mask & 0xff)])
def ifconfig(self):
nifs = self.qga.network_get_interfaces()
msgs = []
for nif in nifs:
msgs.append(nif['name'] + ':')
if 'ip-addresses' in nif:
for ipaddr in nif['ip-addresses']:
if ipaddr['ip-address-type'] == 'ipv4':
addr = ipaddr['ip-address']
mask = self.__gen_ipv4_netmask(int(ipaddr['prefix']))
msgs.append(f"\tinet {addr} netmask {mask}")
elif ipaddr['ip-address-type'] == 'ipv6':
addr = ipaddr['ip-address']
prefix = ipaddr['prefix']
msgs.append(f"\tinet6 {addr} prefixlen {prefix}")
if nif['hardware-address'] != '00:00:00:00:00:00':
msgs.append("\tether " + nif['hardware-address'])
return '\n'.join(msgs)
def ping(self, timeout):
self.qga.settimeout(timeout)
try:
self.qga.ping()
except TimeoutError:
return False
return True
def fsfreeze(self, cmd):
if cmd not in ['status', 'freeze', 'thaw']:
raise Exception('Invalid command: ' + cmd)
return getattr(self.qga, 'fsfreeze' + '_' + cmd)()
def fstrim(self, minimum=0):
return getattr(self.qga, 'fstrim')(minimum=minimum)
def suspend(self, mode):
if mode not in ['disk', 'ram', 'hybrid']:
raise Exception('Invalid mode: ' + mode)
try:
getattr(self.qga, 'suspend' + '_' + mode)()
# On error exception will raise
except self.qga.timeout:
# On success command will timed out
return
def shutdown(self, mode='powerdown'):
if mode not in ['powerdown', 'halt', 'reboot']:
raise Exception('Invalid mode: ' + mode)
try:
self.qga.shutdown(mode=mode)
except self.qga.timeout:
return
def _cmd_cat(client, args):
if len(args) != 1:
print('Invalid argument')
print('Usage: cat <file>')
sys.exit(1)
print(client.read(args[0]))
def _cmd_fsfreeze(client, args):
usage = 'Usage: fsfreeze status|freeze|thaw'
if len(args) != 1:
print('Invalid argument')
print(usage)
sys.exit(1)
if args[0] not in ['status', 'freeze', 'thaw']:
print('Invalid command: ' + args[0])
print(usage)
sys.exit(1)
cmd = args[0]
ret = client.fsfreeze(cmd)
if cmd == 'status':
print(ret)
elif cmd == 'freeze':
print("%d filesystems frozen" % ret)
else:
print("%d filesystems thawed" % ret)
def _cmd_fstrim(client, args):
if len(args) == 0:
minimum = 0
else:
minimum = int(args[0])
print(client.fstrim(minimum))
def _cmd_ifconfig(client, args):
assert not args
print(client.ifconfig())
def _cmd_info(client, args):
assert not args
print(client.info())
def _cmd_ping(client, args):
if len(args) == 0:
timeout = 3
else:
timeout = float(args[0])
alive = client.ping(timeout)
if not alive:
print("Not responded in %s sec" % args[0])
sys.exit(1)
def _cmd_suspend(client, args):
usage = 'Usage: suspend disk|ram|hybrid'
if len(args) != 1:
print('Less argument')
print(usage)
sys.exit(1)
if args[0] not in ['disk', 'ram', 'hybrid']:
print('Invalid command: ' + args[0])
print(usage)
sys.exit(1)
client.suspend(args[0])
def _cmd_shutdown(client, args):
assert not args
client.shutdown()
_cmd_powerdown = _cmd_shutdown
def _cmd_halt(client, args):
assert not args
client.shutdown('halt')
def _cmd_reboot(client, args):
assert not args
client.shutdown('reboot')
commands = [m.replace('_cmd_', '') for m in dir() if '_cmd_' in m]
def send_command(address, cmd, args):
if not os.path.exists(address):
print('%s not found' % address)
sys.exit(1)
if cmd not in commands:
print('Invalid command: ' + cmd)
print('Available commands: ' + ', '.join(commands))
sys.exit(1)
try:
client = QemuGuestAgentClient(address)
except OSError as err:
print(err)
if err.errno == errno.ECONNREFUSED:
print('Hint: qemu is not running?')
sys.exit(1)
if cmd == 'fsfreeze' and args[0] == 'freeze':
client.sync(60)
elif cmd != 'ping':
client.sync()
globals()['_cmd_' + cmd](client, args)
def main():
address = os.environ.get('QGA_CLIENT_ADDRESS')
parser = argparse.ArgumentParser()
parser.add_argument('--address', action='store',
default=address,
help='Specify a ip:port pair or a unix socket path')
parser.add_argument('command', choices=commands)
parser.add_argument('args', nargs='*')
args = parser.parse_args()
if args.address is None:
parser.error('address is not specified')
sys.exit(1)
send_command(args.address, args.command, args.args)
if __name__ == '__main__':
main()