* [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool
@ 2017-08-30 17:14 Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 1/3] backup: " Ishani Chugh
` (3 more replies)
0 siblings, 4 replies; 7+ messages in thread
From: Ishani Chugh @ 2017-08-30 17:14 UTC (permalink / raw)
To: qemu-devel; +Cc: stefanha, jsnow, famz, Ishani Chugh
This patch series is intended to introduce QEMU Backup tool.
qemu-backup will be a command-line tool for performing full and
incremental disk backups on running VMs. It is intended as a
reference implementation for management stack and backup developers
to see QEMU's backup features in action.
This patch series contains three patches,
1) QEMU Backup command line tool.
2) Test for full backup.
3) Manpage for the tool.
v3:
* Added versioning in config file
* Replace location by qemu-img convert in restore
* Removed incremental backup documentation from manpage
Ishani Chugh (3):
backup: QEMU Backup Tool
Test for full Backup
Add manpage for QEMU Backup Tool
Makefile | 14 +-
contrib/backup/qemu-backup.py | 343 ++++++++++++++++++++++++++++++++++++++++
contrib/backup/qemu-backup.texi | 142 +++++++++++++++++
tests/qemu-iotests/191 | 86 ++++++++++
tests/qemu-iotests/191.out | 35 ++++
tests/qemu-iotests/group | 2 +
6 files changed, 618 insertions(+), 4 deletions(-)
create mode 100644 contrib/backup/qemu-backup.py
create mode 100644 contrib/backup/qemu-backup.texi
create mode 100755 tests/qemu-iotests/191
create mode 100644 tests/qemu-iotests/191.out
--
2.7.4
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v3 1/3] backup: QEMU Backup Tool
2017-08-30 17:14 [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool Ishani Chugh
@ 2017-08-30 17:14 ` Ishani Chugh
2017-09-01 22:47 ` John Snow
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 2/3] Test for full Backup Ishani Chugh
` (2 subsequent siblings)
3 siblings, 1 reply; 7+ messages in thread
From: Ishani Chugh @ 2017-08-30 17:14 UTC (permalink / raw)
To: qemu-devel; +Cc: stefanha, jsnow, famz, Ishani Chugh
qemu-backup will be a command-line tool for performing full and
incremental disk backups on running VMs. It is intended as a
reference implementation for management stack and backup developers
to see QEMU's backup features in action. The tool writes details of
guest in a configuration file and the data is retrieved from the file
while creating a backup. The location of config file can be set as an
environment variable QEMU_BACKUP_CONFIG. The usage is as follows:
Add a guest
python qemu-backup.py guest add --guest <guest_name> --qmp <socket_path>
Add a drive for backup in a specified guest
python qemu-backup.py drive add --guest <guest_name> --id <drive_id> [--target <target_file_path>]
Create backup of the added drives:
python qemu-backup.py backup --guest <guest_name>
List all guest configs in configuration file:
python qemu-backup.py guest list
Restore operation
python qemu-backup.py restore --guest <guest-name>
Remove a guest
python qemu-backup.py guest remove --guest <guest_name>
Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
---
contrib/backup/qemu-backup.py | 343 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 343 insertions(+)
create mode 100644 contrib/backup/qemu-backup.py
diff --git a/contrib/backup/qemu-backup.py b/contrib/backup/qemu-backup.py
new file mode 100644
index 0000000..248ca9f
--- /dev/null
+++ b/contrib/backup/qemu-backup.py
@@ -0,0 +1,343 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2017 Ishani Chugh <chugh.ishani@research.iiit.ac.in>
+#
+# 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/>.
+#
+
+"""
+This file is an implementation of backup tool
+"""
+from __future__ import print_function
+from argparse import ArgumentParser
+import os
+import errno
+from socket import error as socket_error
+try:
+ import configparser
+except ImportError:
+ import ConfigParser as configparser
+import sys
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..',
+ 'scripts', 'qmp'))
+from qmp import QEMUMonitorProtocol
+
+
+class BackupTool(object):
+ """BackupTool Class"""
+ def __init__(self, config_file=os.path.expanduser('~') +
+ '/.config/qemu/qemu-backup-config'):
+ if "QEMU_BACKUP_CONFIG" in os.environ:
+ self.config_file = os.environ["QEMU_BACKUP_CONFIG"]
+
+ else:
+ self.config_file = config_file
+ try:
+ if not os.path.isdir(os.path.dirname(self.config_file)):
+ os.makedirs(os.path.dirname(self.config_file))
+ except:
+ print("Cannot create config directory", file=sys.stderr)
+ sys.exit(1)
+ self.config = configparser.ConfigParser()
+ self.config.read(self.config_file)
+ try:
+ if self.config.get('general', 'version') != '1.0':
+ print("Version Conflict in config file", file=sys.stderr)
+ sys.exit(1)
+ except:
+ self.config['general'] = {'version': '1.0'}
+ self.write_config()
+
+ def write_config(self):
+ """
+ Writes configuration to ini file.
+ """
+ config_file = open(self.config_file + ".tmp", 'w')
+ self.config.write(config_file)
+ config_file.flush()
+ os.fsync(config_file.fileno())
+ config_file.close()
+ os.rename(self.config_file + ".tmp", self.config_file)
+
+ def get_socket_address(self, socket_address):
+ """
+ Return Socket address in form of string or tuple
+ """
+ if socket_address.startswith('tcp'):
+ return (socket_address.split(':')[1],
+ int(socket_address.split(':')[2]))
+ return socket_address.split(':', 2)[1]
+
+ def _full_backup(self, guest_name):
+ """
+ Performs full backup of guest
+ """
+ if guest_name not in self.config.sections():
+ print("Cannot find specified guest", file=sys.stderr)
+ sys.exit(1)
+
+ self.verify_guest_running(guest_name)
+ connection = QEMUMonitorProtocol(
+ self.get_socket_address(
+ self.config[guest_name]['qmp']))
+ connection.connect()
+ cmd = {"execute": "transaction", "arguments": {"actions": []}}
+ drive_list = []
+ for key in self.config[guest_name]:
+ if key.startswith("drive_"):
+ drive = key[len('drive_'):]
+ drive_list.append(drive)
+ target = self.config[guest_name][key]
+ sub_cmd = {"type": "drive-backup", "data": {"device": drive,
+ "target": target,
+ "sync": "full"}}
+ cmd['arguments']['actions'].append(sub_cmd)
+ qmp_return = connection.cmd_obj(cmd)
+ if 'error' in qmp_return:
+ print(qmp_return['error']['desc'], file=sys.stderr)
+ sys.exit(1)
+ print("Backup Started")
+ while drive_list:
+ event = connection.pull_event(wait=True)
+ if event['event'] == 'SHUTDOWN':
+ print("The guest was SHUT DOWN", file=sys.stderr)
+ sys.exit(1)
+
+ if event['event'] == 'BLOCK_JOB_COMPLETED':
+ if event['data']['device'] in drive_list and \
+ event['data']['type'] == 'backup':
+ print("*" + event['data']['device'])
+ drive_list.remove(event['data']['device'])
+
+ if event['event'] == 'BLOCK_JOB_ERROR':
+ if event['data']['device'] in drive_list and \
+ event['data']['type'] == 'backup':
+ print(event['data']['device'] + " Backup Failed",
+ file=sys.stderr)
+ drive_list.remove(event['data']['device'])
+ print("Backup Complete")
+
+ def _drive_add(self, drive_id, guest_name, target=None):
+ """
+ Adds drive for backup
+ """
+ if target is None:
+ target = os.path.abspath(drive_id)
+
+ if os.path.isdir(os.path.dirname(target)) is False:
+ print("Cannot find target directory", file=sys.stderr)
+ sys.exit(1)
+
+ if guest_name not in self.config.sections():
+ print("Cannot find specified guest", file=sys.stderr)
+ sys.exit(1)
+
+ if "drive_" + drive_id in self.config[guest_name]:
+ print("Drive already marked for backup", file=sys.stderr)
+ sys.exit(1)
+
+ self.verify_guest_running(guest_name)
+
+ connection = QEMUMonitorProtocol(
+ self.get_socket_address(
+ self.config[guest_name]['qmp']))
+ connection.connect()
+ cmd = {'execute': 'query-block'}
+ returned_json = connection.cmd_obj(cmd)
+ device_present = False
+ for device in returned_json['return']:
+ if device['device'] == drive_id:
+ device_present = True
+ break
+
+ if not device_present:
+ print("No such drive in guest", file=sys.stderr)
+ sys.exit(1)
+
+ drive_id = "drive_" + drive_id
+ for d_id in self.config[guest_name]:
+ if self.config[guest_name][d_id] == target:
+ print("Please choose different target", file=sys.stderr)
+ sys.exit(1)
+ self.config.set(guest_name, drive_id, target)
+ self.write_config()
+ print("Successfully Added Drive")
+
+ def verify_guest_running(self, guest_name):
+ """
+ Checks whether specified guest is running or not
+ """
+ socket_address = self.config.get(guest_name, 'qmp')
+ try:
+ connection = QEMUMonitorProtocol(self.get_socket_address(
+ socket_address))
+ connection.connect()
+ except socket_error:
+ if socket_error.errno != errno.ECONNREFUSED:
+ print("Connection to guest refused", file=sys.stderr)
+ sys.exit(1)
+
+ def _guest_add(self, guest_name, socket_address):
+ """
+ Adds a guest to the config file
+ """
+ if guest_name in self.config.sections():
+ print("ID already exists. Please choose a different guest name",
+ file=sys.stderr)
+ sys.exit(1)
+ self.config[guest_name] = {'qmp': socket_address}
+ self.verify_guest_running(guest_name)
+ self.write_config()
+ print("Successfully Added Guest")
+
+ def _guest_remove(self, guest_name):
+ """
+ Removes a guest from config file
+ """
+ if guest_name not in self.config.sections():
+ print("Guest Not present", file=sys.stderr)
+ sys.exit(1)
+ self.config.remove_section(guest_name)
+ print("Guest successfully deleted")
+
+ def _restore(self, guest_name):
+ """
+ Prints Steps to perform restore operation
+ """
+ if guest_name not in self.config.sections():
+ print("Cannot find specified guest", file=sys.stderr)
+ sys.exit(1)
+
+ self.verify_guest_running(guest_name)
+ connection = QEMUMonitorProtocol(
+ self.get_socket_address(
+ self.config[guest_name]['qmp']))
+ connection.connect()
+ print("To perform restore:")
+ print("Shut down guest")
+ for key in self.config[guest_name]:
+ if key.startswith("drive_"):
+ drive = key[len('drive_'):]
+ target = self.config[guest_name][key]
+ cmd = {'execute': 'query-block'}
+ returned_json = connection.cmd_obj(cmd)
+ device_present = False
+ for device in returned_json['return']:
+ if device['device'] == drive:
+ device_present = True
+ location = device['inserted']['image']['filename']
+ print("qemu-img convert " + target + " " + location)
+
+ if not device_present:
+ print("No such drive in guest", file=sys.stderr)
+ sys.exit(1)
+
+ def guest_remove_wrapper(self, args):
+ """
+ Wrapper for _guest_remove method.
+ """
+ guest_name = args.guest
+ self._guest_remove(guest_name)
+ self.write_config()
+
+ def list(self, args):
+ """
+ Prints guests present in Config file
+ """
+ for guest_name in self.config.sections():
+ print(guest_name)
+
+ def guest_add_wrapper(self, args):
+ """
+ Wrapper for _quest_add method
+ """
+ self._guest_add(args.guest, args.qmp)
+
+ def drive_add_wrapper(self, args):
+ """
+ Wrapper for _drive_add method
+ """
+ self._drive_add(args.id, args.guest, args.target)
+
+ def fullbackup_wrapper(self, args):
+ """
+ Wrapper for _full_backup method
+ """
+ self._full_backup(args.guest)
+
+ def restore_wrapper(self, args):
+ """
+ Wrapper for restore
+ """
+ self._restore(args.guest)
+
+
+def main():
+ backup_tool = BackupTool()
+ parser = ArgumentParser()
+ subparsers = parser.add_subparsers(title='Subcommands',
+ description='Valid Subcommands',
+ help='Subcommand help')
+ guest_parser = subparsers.add_parser('guest', help='Adds or \
+ removes and lists guest(s)')
+ guest_subparsers = guest_parser.add_subparsers(title='Guest Subparser')
+ guest_list_parser = guest_subparsers.add_parser('list',
+ help='Lists all guests')
+ guest_list_parser.set_defaults(func=backup_tool.list)
+
+ guest_add_parser = guest_subparsers.add_parser('add', help='Adds a guest')
+ guest_add_parser.add_argument('--guest', action='store', type=str,
+ help='Name of the guest')
+ guest_add_parser.add_argument('--qmp', action='store', type=str,
+ help='Path of socket')
+ guest_add_parser.set_defaults(func=backup_tool.guest_add_wrapper)
+
+ guest_remove_parser = guest_subparsers.add_parser('remove',
+ help='removes a guest')
+ guest_remove_parser.add_argument('--guest', action='store', type=str,
+ help='Name of the guest')
+ guest_remove_parser.set_defaults(func=backup_tool.guest_remove_wrapper)
+
+ drive_parser = subparsers.add_parser('drive',
+ help='Adds drive(s) for backup')
+ drive_subparsers = drive_parser.add_subparsers(title='Add subparser',
+ description='Drive \
+ subparser')
+ drive_add_parser = drive_subparsers.add_parser('add',
+ help='Adds new \
+ drive for backup')
+ drive_add_parser.add_argument('--guest', action='store',
+ type=str, help='Name of the guest')
+ drive_add_parser.add_argument('--id', action='store',
+ type=str, help='Drive ID')
+ drive_add_parser.add_argument('--target', nargs='?',
+ default=None, help='Destination path')
+ drive_add_parser.set_defaults(func=backup_tool.drive_add_wrapper)
+
+ backup_parser = subparsers.add_parser('backup', help='Creates backup')
+ backup_parser.add_argument('--guest', action='store',
+ type=str, help='Name of the guest')
+ backup_parser.set_defaults(func=backup_tool.fullbackup_wrapper)
+
+ backup_parser = subparsers.add_parser('restore', help='Restores drives')
+ backup_parser.add_argument('--guest', action='store',
+ type=str, help='Name of the guest')
+ backup_parser.set_defaults(func=backup_tool.restore_wrapper)
+
+ args = parser.parse_args()
+ args.func(args)
+
+if __name__ == '__main__':
+ main()
--
2.7.4
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v3 2/3] Test for full Backup
2017-08-30 17:14 [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 1/3] backup: " Ishani Chugh
@ 2017-08-30 17:14 ` Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 3/3] Add manpage for QEMU Backup Tool Ishani Chugh
2017-08-31 1:09 ` [Qemu-devel] [PATCH v3 0/3] " Fam Zheng
3 siblings, 0 replies; 7+ messages in thread
From: Ishani Chugh @ 2017-08-30 17:14 UTC (permalink / raw)
To: qemu-devel; +Cc: stefanha, jsnow, famz, Ishani Chugh
This patch is the test for full backup implementation in Backup tool.
The test employs two basic substests:
1) Backing up an empty guest and comparing it with base image.
2) Writing a pattern to the guest, creating backup and comparing
with the base image.
Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
---
tests/qemu-iotests/191 | 86 ++++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/191.out | 35 +++++++++++++++++++
tests/qemu-iotests/group | 2 ++
3 files changed, 123 insertions(+)
create mode 100755 tests/qemu-iotests/191
create mode 100644 tests/qemu-iotests/191.out
diff --git a/tests/qemu-iotests/191 b/tests/qemu-iotests/191
new file mode 100755
index 0000000..16988d8
--- /dev/null
+++ b/tests/qemu-iotests/191
@@ -0,0 +1,86 @@
+#!/bin/bash
+#
+# Test full backup functionality of qemu-backup tool
+#
+# Copyright (C) 2017 Ishani Chugh <chugh.ishani@research.iiit.ac.in>
+#
+# 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/>.
+#
+
+# creator
+owner=chugh.ishani@research.iiit.ac.in
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+here=`pwd`
+status=1 # failure is the default!
+
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+. ./common.qemu
+
+_supported_fmt generic
+_supported_proto generic
+_supported_os Linux
+
+_cleanup()
+{
+ rm -f "$TEST_DIR"/virtio0
+ rm -f "$CONFIG_FILE"
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+CONFIG_FILE="$TEST_DIR"/backup-config
+SOCKET=unix:"$TEST_DIR"/backup_socket
+size=128M
+
+_make_test_img "$size"
+export QEMU_BACKUP_CONFIG="$CONFIG_FILE"
+qemu_comm_method="monitor"
+echo
+_launch_qemu -drive if=virtio,file="$TEST_IMG" -qmp "$SOCKET",server,nowait
+$PYTHON ../../contrib/backup/qemu-backup.py guest add --guest adad --qmp "$SOCKET"
+$PYTHON ../../contrib/backup/qemu-backup.py drive add --id virtio0 --guest adad --target "$TEST_DIR"/virtio0
+echo
+echo "== Creating backup =="
+$PYTHON ../../contrib/backup/qemu-backup.py backup --guest adad
+_send_qemu_cmd $QEMU_HANDLE 'quit' ''
+wait=1 _cleanup_qemu
+echo
+echo "== Comparing images =="
+$QEMU_IMG compare "$TEST_DIR"/virtio0 "$TEST_IMG"
+_cleanup
+
+_launch_qemu -drive if=virtio,id=virtio0,file="$TEST_IMG" -qmp "$SOCKET",server,nowait
+$PYTHON ../../contrib/backup/qemu-backup.py guest add --guest adad --qmp "$SOCKET"
+$PYTHON ../../contrib/backup/qemu-backup.py drive add --id virtio0 --guest adad --target "$TEST_DIR"/virtio0
+echo
+echo "== Writing Pattern =="
+_send_qemu_cmd $QEMU_HANDLE 'qemu-io virtio0 "write -P 0x22 0 1M"' "(qemu)" | _filter_qemu_io
+echo
+echo "== Creating backup =="
+$PYTHON ../../contrib/backup/qemu-backup.py backup --guest adad
+_send_qemu_cmd $QEMU_HANDLE 'quit' ''
+wait=1 _cleanup_qemu
+echo
+echo "== Comparing images =="
+$QEMU_IMG compare "$TEST_DIR"/virtio0 "$TEST_IMG"
+_cleanup
+_cleanup_test_img
+
+echo "*** done"
+status=0
\ No newline at end of file
diff --git a/tests/qemu-iotests/191.out b/tests/qemu-iotests/191.out
new file mode 100644
index 0000000..c60d47a
--- /dev/null
+++ b/tests/qemu-iotests/191.out
@@ -0,0 +1,35 @@
+QA output created by 191
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+
+Successfully Added Guest
+Successfully Added Drive
+
+== Creating backup ==
+Backup Started
+*virtio0
+Backup Complete
+QEMU X.Y.Z monitor - type 'help' for more information
+(qemu) Formatting 'TEST_DIR/virtio0', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+quit
+
+== Comparing images ==
+Images are identical.
+Successfully Added Guest
+Successfully Added Drive
+
+== Writing Pattern ==
+QEMU X.Y.Z monitor - type 'help' for more information
+(qemu) qemu-io virtio0 "write -P 0x22 0 1M"
+
+== Creating backup ==
+Backup Started
+*virtio0
+Backup Complete
+wrote 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+(qemu) Formatting 'TEST_DIR/virtio0', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+quit
+
+== Comparing images ==
+Images are identical.
+*** done
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index afbdc42..66fa231 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -186,4 +186,6 @@
188 rw auto quick
189 rw auto
190 rw auto quick
+191 rw auto
192 rw auto quick
+193 rw auto
--
2.7.4
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v3 3/3] Add manpage for QEMU Backup Tool
2017-08-30 17:14 [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 1/3] backup: " Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 2/3] Test for full Backup Ishani Chugh
@ 2017-08-30 17:14 ` Ishani Chugh
2017-08-31 1:09 ` [Qemu-devel] [PATCH v3 0/3] " Fam Zheng
3 siblings, 0 replies; 7+ messages in thread
From: Ishani Chugh @ 2017-08-30 17:14 UTC (permalink / raw)
To: qemu-devel; +Cc: stefanha, jsnow, famz, Ishani Chugh
qemu-backup will be a command-line tool for performing full and
incremental disk backups on running VMs. It is intended as a
reference implementation for management stack and backup developers
to see QEMU's backup features in action. This commit is an
initial implementation of manpage listing the commands which the
backup tool will support. The manpage will be built along with other
docs when configure is provided with --enable-docs flag in the
location contrib/backup in build directory.
Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
---
Makefile | 14 ++--
contrib/backup/qemu-backup.texi | 142 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 152 insertions(+), 4 deletions(-)
create mode 100644 contrib/backup/qemu-backup.texi
diff --git a/Makefile b/Makefile
index 81447b1..ba1574d 100644
--- a/Makefile
+++ b/Makefile
@@ -209,6 +209,7 @@ ifdef BUILD_DOCS
DOCS=qemu-doc.html qemu-doc.txt qemu.1 qemu-img.1 qemu-nbd.8 qemu-ga.8
DOCS+=docs/interop/qemu-qmp-ref.html docs/interop/qemu-qmp-ref.txt docs/interop/qemu-qmp-ref.7
DOCS+=docs/interop/qemu-ga-ref.html docs/interop/qemu-ga-ref.txt docs/interop/qemu-ga-ref.7
+DOCS+=contrib/backup/qemu-backup.html contrib/backup/qemu-backup.txt
ifdef CONFIG_VIRTFS
DOCS+=fsdev/virtfs-proxy-helper.1
endif
@@ -508,6 +509,8 @@ VERSION ?= $(shell cat VERSION)
dist: qemu-$(VERSION).tar.bz2
+qemu-backup.8: contrib/backup/qemu-backup.texi
+
qemu-%.tar.bz2:
$(SRC_PATH)/scripts/make-release "$(SRC_PATH)" "$(patsubst qemu-%.tar.bz2,%,$@)"
@@ -719,16 +722,19 @@ fsdev/virtfs-proxy-helper.1: fsdev/virtfs-proxy-helper.texi
qemu-nbd.8: qemu-nbd.texi qemu-option-trace.texi
qemu-ga.8: qemu-ga.texi
-html: qemu-doc.html docs/interop/qemu-qmp-ref.html docs/interop/qemu-ga-ref.html
-info: qemu-doc.info docs/interop/qemu-qmp-ref.info docs/interop/qemu-ga-ref.info
-pdf: qemu-doc.pdf docs/interop/qemu-qmp-ref.pdf docs/interop/qemu-ga-ref.pdf
-txt: qemu-doc.txt docs/interop/qemu-qmp-ref.txt docs/interop/qemu-ga-ref.txt
+html: qemu-doc.html docs/interop/qemu-qmp-ref.html docs/interop/qemu-ga-ref.html contrib/backup/qemu-backup.html
+info: qemu-doc.info docs/interop/qemu-qmp-ref.info docs/interop/qemu-ga-ref.info contrib/backup/qemu-backup.info
+pdf: qemu-doc.pdf docs/interop/qemu-qmp-ref.pdf docs/interop/qemu-ga-ref.pdf contrib/backup/qemu-backup.pdf
+txt: qemu-doc.txt docs/interop/qemu-qmp-ref.txt docs/interop/qemu-ga-ref.txt contrib/backup/qemu-backup.txt
qemu-doc.html qemu-doc.info qemu-doc.pdf qemu-doc.txt: \
qemu-img.texi qemu-nbd.texi qemu-options.texi qemu-option-trace.texi \
qemu-monitor.texi qemu-img-cmds.texi qemu-ga.texi \
qemu-monitor-info.texi
+contrib/backup/qemu-backup.html contrib/backup/qemu-backup.pdf contrib/backup/qemu-backup.txt contrib/backup/qemu-backup.info: \
+ contrib/backup/qemu-backup.texi
+
docs/interop/qemu-ga-ref.dvi docs/interop/qemu-ga-ref.html \
docs/interop/qemu-ga-ref.info docs/interop/qemu-ga-ref.pdf \
docs/interop/qemu-ga-ref.txt docs/interop/qemu-ga-ref.7: \
diff --git a/contrib/backup/qemu-backup.texi b/contrib/backup/qemu-backup.texi
new file mode 100644
index 0000000..7ad266c
--- /dev/null
+++ b/contrib/backup/qemu-backup.texi
@@ -0,0 +1,142 @@
+\input texinfo
+@setfilename qemu-backup
+
+@documentlanguage en
+@documentencoding UTF-8
+
+@settitle QEMU Backup Tool
+@copying
+
+Copyright @copyright{} 2017 The QEMU Project developers
+@end copying
+@ifinfo
+@direntry
+* QEMU: (QEMU-backup). Man page for QEMU Backup Tool.
+@end direntry
+@end ifinfo
+@iftex
+@titlepage
+@sp 7
+@center @titlefont{QEMU Backup Tool}
+@sp 1
+@sp 3
+@end titlepage
+@end iftex
+@ifnottex
+@node Top
+@top Short Sample
+
+@menu
+* Name::
+* Synopsis::
+* List of Commands::
+* Command Parameters::
+* Command Descriptions::
+* License::
+@end menu
+
+@end ifnottex
+
+@node Name
+@chapter Name
+
+QEMU disk backup tool.
+
+@node Synopsis
+@chapter Synopsis
+
+qemu-backup command [command options].
+
+@node List of Commands
+@chapter List of Commands
+@itemize
+@item qemu-backup guest add --guest guestname --qmp socketpath
+@item qemu-backup guest list
+@item qemu-backup drive add --id driveid --guest guestname --target target
+@item qemu-backup drive add --all --guest guestname --target target
+@item qemu-backup drive list --guest guestname
+@item qemu-backup restore --guest guestname
+@item qemu-backup guest remove --guest guestname
+@item qemu-backup drive remove --guest guestname --id driveid
+@end itemize
+@node Command Parameters
+@chapter Command Parameters
+@itemize
+@item --all: Add all the drives present in a guest which are suitable for backup.
+@item --guest: Name of the guest.
+@item --id: id of guest or drive.
+@item --qmp: Path of qmp socket.
+@item --target: Destination path on which you want your backup to be made.
+@end itemize
+
+@node Command Descriptions
+@chapter Command Descriptions
+@itemize
+@item qemu-backup guest add --guest guestname --qmp socketpath
+This command adds a guest to the configuration file given its path to qmp socket.
+
+example:
+qemu-backup guest add --id=fedora --qmp=unix:/var/run/qemu/fedora.sock
+
+qemu-backup guest add --id=fedora --qmp=tcp:localhost:4444
+
+@item qemu-backup guest list
+This commands lists the names of guests which are added to configuration file.
+
+@item qemu-backup drive add --guest guestname --id driveid --target target
+This command adds different drives for backup in a particular guest by giving the name of drive to be backed up and target imagefile in which we want to store the drive backup.
+
+example: qemu-backup drive add --guest=fedora --id=root --target=/backup/root.img
+
+@item qemu-backup drive add --all --guest guestname --destination destination
+This command adds all the drives of the guest for backup other than CDROM drive and read-only drives. Here all the backup drives will have the same names as original drives and target will be the destination folder.
+
+example: qemu-backup drive add --all --guest fedora --destination =/backup/fedora/
+
+@item qemu-backup drive list --guest guestname
+This commands gives the names of the drive present in a guest which are added for backup.
+
+example: qemu-backup drive list --guest=fedora
+
+@item qemu-backup backup --guest guestname
+
+This command makes the backup of the drives, in their respective given destinations. The ids of drive and their destinations are taken from the configuration file.
+
+example: qemu-backup backup --guest=fedora
+
+@item qemu-backup restore --guest guestname
+This command is needed if we want to restore the backup. It will list the commands to be run for performing the same but will not perform any action.
+
+example: qemu-backup restore --guest=fedora
+
+@item qemu-backup guest remove --guest guestname
+This command removes the guest from the configuration file.
+
+example: qemu-backup guest remove --guest=fedora
+
+@item qemu-backup drive remove --guest guestname --id driveid
+This command helps remove a drive which is set for backup in configuration of given host.
+
+example: drive remove --guest=fedora --id=root
+
+@item A full backup can be performed by following the given steps:
+
+Perform a full backup of 'vm001', which has one drive:
+
+qemu-backup guest add --guest vm001 --qmp /path/to/vm001.sock
+
+qemu-backup add --id drive0 --guest vm001 --target /backups/vm001-drive0.img
+
+qemu-backup backup --guest vm001
+
+
+@end itemize
+
+@node License
+@appendix License
+QEMU is a trademark of Fabrice Bellard.
+QEMU is released under the
+@url{https://www.gnu.org/licenses/gpl-2.0.txt,GNU General Public License},
+version 2. Parts of QEMU have specific licenses, see file
+@url{http://git.qemu.org/?p=qemu.git;a=blob_plain;f=LICENSE,LICENSE}.
+@bye
--
2.7.4
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool
2017-08-30 17:14 [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool Ishani Chugh
` (2 preceding siblings ...)
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 3/3] Add manpage for QEMU Backup Tool Ishani Chugh
@ 2017-08-31 1:09 ` Fam Zheng
3 siblings, 0 replies; 7+ messages in thread
From: Fam Zheng @ 2017-08-31 1:09 UTC (permalink / raw)
To: Ishani Chugh; +Cc: qemu-devel, stefanha, jsnow
On Wed, 08/30 22:44, Ishani Chugh wrote:
> This patch series is intended to introduce QEMU Backup tool.
> qemu-backup will be a command-line tool for performing full and
> incremental disk backups on running VMs. It is intended as a
> reference implementation for management stack and backup developers
> to see QEMU's backup features in action.
> This patch series contains three patches,
> 1) QEMU Backup command line tool.
> 2) Test for full backup.
> 3) Manpage for the tool.
> v3:
> * Added versioning in config file
> * Replace location by qemu-img convert in restore
> * Removed incremental backup documentation from manpage
Reviewed-by: Fam Zheng <famz@redhat.com>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v3 1/3] backup: QEMU Backup Tool
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 1/3] backup: " Ishani Chugh
@ 2017-09-01 22:47 ` John Snow
2017-09-08 11:06 ` Ishani
0 siblings, 1 reply; 7+ messages in thread
From: John Snow @ 2017-09-01 22:47 UTC (permalink / raw)
To: Ishani Chugh, qemu-devel; +Cc: famz, stefanha
I suggest as your commit message here, something like:
"backup: Add QEMU backup tool"
A good commit message should say what applying the patch will do:
"What will happen if I apply this patch?"
"It will 'Add QEMU backup tool'"
On 08/30/2017 01:14 PM, Ishani Chugh wrote:
> qemu-backup will be a command-line tool for performing full and
> incremental disk backups on running VMs. It is intended as a
> reference implementation for management stack and backup developers
> to see QEMU's backup features in action. The tool writes details of
> guest in a configuration file and the data is retrieved from the file
> while creating a backup. The location of config file can be set as an
> environment variable QEMU_BACKUP_CONFIG. The usage is as follows:
>
> Add a guest
> python qemu-backup.py guest add --guest <guest_name> --qmp <socket_path>
>
This should probably be organized by subcommand, so:
guest add
guest remove
guest list
drive add
backup
restore
> Add a drive for backup in a specified guest
> python qemu-backup.py drive add --guest <guest_name> --id <drive_id> [--target <target_file_path>]
>
> Create backup of the added drives:
> python qemu-backup.py backup --guest <guest_name>
>
> List all guest configs in configuration file:
> python qemu-backup.py guest list
>
> Restore operation
> python qemu-backup.py restore --guest <guest-name>
>
> Remove a guest
> python qemu-backup.py guest remove --guest <guest_name>
>
Looks good, but the man page should perhaps be patch 01 instead of 03 so
that the usage can be reviewed outside of the commit message.
> Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
> ---
> contrib/backup/qemu-backup.py | 343 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 343 insertions(+)
> create mode 100644 contrib/backup/qemu-backup.py
>
> diff --git a/contrib/backup/qemu-backup.py b/contrib/backup/qemu-backup.py
> new file mode 100644
> index 0000000..248ca9f
> --- /dev/null
> +++ b/contrib/backup/qemu-backup.py
> @@ -0,0 +1,343 @@
> +#!/usr/bin/python
> +# -*- coding: utf-8 -*-
> +#
> +# Copyright (C) 2017 Ishani Chugh <chugh.ishani@research.iiit.ac.in>
> +#
> +# 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/>.
> +#
> +
> +"""
> +This file is an implementation of backup tool
> +"""
> +from __future__ import print_function
> +from argparse import ArgumentParser
> +import os
> +import errno
> +from socket import error as socket_error
> +try:
> + import configparser
> +except ImportError:
> + import ConfigParser as configparser
> +import sys
> +sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..',
> + 'scripts', 'qmp'))
> +from qmp import QEMUMonitorProtocol
> +
> +
> +class BackupTool(object):
> + """BackupTool Class"""
> + def __init__(self, config_file=os.path.expanduser('~') +
> + '/.config/qemu/qemu-backup-config'):
> + if "QEMU_BACKUP_CONFIG" in os.environ:
> + self.config_file = os.environ["QEMU_BACKUP_CONFIG"]
> +
> + else:
> + self.config_file = config_file
> + try:
> + if not os.path.isdir(os.path.dirname(self.config_file)):
> + os.makedirs(os.path.dirname(self.config_file))
> + except:
> + print("Cannot create config directory", file=sys.stderr)
> + sys.exit(1)
> + self.config = configparser.ConfigParser()
> + self.config.read(self.config_file)
> + try:
> + if self.config.get('general', 'version') != '1.0':
> + print("Version Conflict in config file", file=sys.stderr)
> + sys.exit(1)
> + except:
> + self.config['general'] = {'version': '1.0'}
> + self.write_config()
> +
> + def write_config(self):
> + """
> + Writes configuration to ini file.
> + """
> + config_file = open(self.config_file + ".tmp", 'w')
> + self.config.write(config_file)
> + config_file.flush()
> + os.fsync(config_file.fileno())
> + config_file.close()
> + os.rename(self.config_file + ".tmp", self.config_file)
> +
> + def get_socket_address(self, socket_address):
> + """
> + Return Socket address in form of string or tuple
> + """
> + if socket_address.startswith('tcp'):
> + return (socket_address.split(':')[1],
> + int(socket_address.split(':')[2]))
> + return socket_address.split(':', 2)[1]
> +
> + def _full_backup(self, guest_name):
> + """
> + Performs full backup of guest
> + """
> + if guest_name not in self.config.sections():
> + print("Cannot find specified guest", file=sys.stderr)
> + sys.exit(1)
> +
> + self.verify_guest_running(guest_name)
> + connection = QEMUMonitorProtocol(
> + self.get_socket_address(
> + self.config[guest_name]['qmp']))
> + connection.connect()
> + cmd = {"execute": "transaction", "arguments": {"actions": []}}
> + drive_list = []
> + for key in self.config[guest_name]:
> + if key.startswith("drive_"):
> + drive = key[len('drive_'):]
> + drive_list.append(drive)
> + target = self.config[guest_name][key]
> + sub_cmd = {"type": "drive-backup", "data": {"device": drive,
> + "target": target,
> + "sync": "full"}}
> + cmd['arguments']['actions'].append(sub_cmd)
> + qmp_return = connection.cmd_obj(cmd)
> + if 'error' in qmp_return:
> + print(qmp_return['error']['desc'], file=sys.stderr)
> + sys.exit(1)
> + print("Backup Started")
> + while drive_list:
> + event = connection.pull_event(wait=True)
> + if event['event'] == 'SHUTDOWN':
> + print("The guest was SHUT DOWN", file=sys.stderr)
> + sys.exit(1)
> +
> + if event['event'] == 'BLOCK_JOB_COMPLETED':
> + if event['data']['device'] in drive_list and \
> + event['data']['type'] == 'backup':
> + print("*" + event['data']['device'])
> + drive_list.remove(event['data']['device'])
> +
> + if event['event'] == 'BLOCK_JOB_ERROR':
> + if event['data']['device'] in drive_list and \
> + event['data']['type'] == 'backup':
> + print(event['data']['device'] + " Backup Failed",
> + file=sys.stderr)
> + drive_list.remove(event['data']['device'])
> + print("Backup Complete")
> +
> + def _drive_add(self, drive_id, guest_name, target=None):
> + """
> + Adds drive for backup
> + """
> + if target is None:
> + target = os.path.abspath(drive_id)
Similar problem as with other commands:
jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py drive add
Traceback (most recent call last):
File "./qemu-backup.py", line 343, in <module>
main()
File "./qemu-backup.py", line 340, in main
args.func(args)
File "./qemu-backup.py", line 272, in drive_add_wrapper
self._drive_add(args.id, args.guest, args.target)
File "./qemu-backup.py", line 137, in _drive_add
target = os.path.abspath(drive_id)
File "/usr/lib64/python2.7/posixpath.py", line 360, in abspath
if not isabs(path):
File "/usr/lib64/python2.7/posixpath.py", line 54, in isabs
return s.startswith('/')
AttributeError: 'NoneType' object has no attribute 'startswith'
This errors out if you don't tell it what drive you want to add.
Meanwhile,
jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py drive add --id
foobar
Cannot find specified guest
Should probably error out because you didn't set the guest name at all.
> +
> + if os.path.isdir(os.path.dirname(target)) is False:
> + print("Cannot find target directory", file=sys.stderr)
> + sys.exit(1)
> +
> + if guest_name not in self.config.sections():
> + print("Cannot find specified guest", file=sys.stderr)
> + sys.exit(1)
> +
> + if "drive_" + drive_id in self.config[guest_name]:
> + print("Drive already marked for backup", file=sys.stderr)
> + sys.exit(1)
> +
> + self.verify_guest_running(guest_name)
> +
> + connection = QEMUMonitorProtocol(
> + self.get_socket_address(
> + self.config[guest_name]['qmp']))
> + connection.connect()
> + cmd = {'execute': 'query-block'}
> + returned_json = connection.cmd_obj(cmd)
> + device_present = False
> + for device in returned_json['return']:
> + if device['device'] == drive_id:
> + device_present = True
> + break
> +
> + if not device_present:
> + print("No such drive in guest", file=sys.stderr)
> + sys.exit(1)
cool!
> +
> + drive_id = "drive_" + drive_id
> + for d_id in self.config[guest_name]:
> + if self.config[guest_name][d_id] == target:
> + print("Please choose different target", file=sys.stderr)
> + sys.exit(1)
> + self.config.set(guest_name, drive_id, target)
> + self.write_config()
> + print("Successfully Added Drive")
> +
> + def verify_guest_running(self, guest_name):
> + """
> + Checks whether specified guest is running or not
> + """
> + socket_address = self.config.get(guest_name, 'qmp')> + try:
> + connection = QEMUMonitorProtocol(self.get_socket_address(
> + socket_address))
> + connection.connect()
> + except socket_error:
> + if socket_error.errno != errno.ECONNREFUSED:
what happens if errno *IS* ECONNREFUSED?
> + print("Connection to guest refused", file=sys.stderr)
> + sys.exit(1)
> +
> + def _guest_add(self, guest_name, socket_address):
> + """
> + Adds a guest to the config file
> + """
> + if guest_name in self.config.sections():
> + print("ID already exists. Please choose a different guest name",
> + file=sys.stderr)
> + sys.exit(1)
> + self.config[guest_name] = {'qmp': socket_address}
> + self.verify_guest_running(guest_name)
> + self.write_config()
> + print("Successfully Added Guest")
this function crashes if you do not provide a guest_name, it should
report an error instead.
./qemu-backup.py guest add
./qemu-backup.py guest add --guest foobar
both crash, please correct.
./qemu-backup.py guest add --guest foobar --qmp foobar
also crashes, please error gracefully if you cannot parse the QMP
argument as a valid socket.
> +
> + def _guest_remove(self, guest_name):
> + """
> + Removes a guest from config file
> + """
> + if guest_name not in self.config.sections():
> + print("Guest Not present", file=sys.stderr)
> + sys.exit(1)
> + self.config.remove_section(guest_name)
> + print("Guest successfully deleted")
> +
If you don't supply a guest name, you get the "Guest Not present" error
message, but really we should error out as if it was a parsing error.
jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py guest remove
--guest general
Guest successfully deleted
Whoops!
> + def _restore(self, guest_name):
> + """
> + Prints Steps to perform restore operation
> + """
> + if guest_name not in self.config.sections():
> + print("Cannot find specified guest", file=sys.stderr)
> + sys.exit(1)
> +
> + self.verify_guest_running(guest_name)
> + connection = QEMUMonitorProtocol(
> + self.get_socket_address(
> + self.config[guest_name]['qmp']))
> + connection.connect()
> + print("To perform restore:")
> + print("Shut down guest")
> + for key in self.config[guest_name]:
> + if key.startswith("drive_"):
> + drive = key[len('drive_'):]
> + target = self.config[guest_name][key]
> + cmd = {'execute': 'query-block'}
> + returned_json = connection.cmd_obj(cmd)
> + device_present = False
> + for device in returned_json['return']:
> + if device['device'] == drive:
> + device_present = True
> + location = device['inserted']['image']['filename']
> + print("qemu-img convert " + target + " " + location)
> +
> + if not device_present:
> + print("No such drive in guest", file=sys.stderr)
> + sys.exit(1)
> +
> + def guest_remove_wrapper(self, args):
> + """
> + Wrapper for _guest_remove method.
> + """
> + guest_name = args.guest
> + self._guest_remove(guest_name)
> + self.write_config()
> +
> + def list(self, args):
> + """
> + Prints guests present in Config file
> + """
> + for guest_name in self.config.sections():
> + print(guest_name)
This will print out "general" too, which I think should be exempted from
this list, as it is not actually a guest!
I propose something like this:
[general]
guests=ishanivm1 ishanivm2 ishanivm3
[guest:ishanivm]
foo=bar
[guest:ishanivm2]
foo=bar2
and so on.
("What happens if someone tries to name a guest 'guest:foobar'? Well,
then the section just gets named 'guest:guest:foobar' and we go about
our happy way.")
Whenever a guest is added or removed, you update the list and delete or
add the corresponding section appropriately.
> +
> + def guest_add_wrapper(self, args):
> + """
> + Wrapper for _quest_add method
s/quest/guest/
> + """
> + self._guest_add(args.guest, args.qmp)
> +> + def drive_add_wrapper(self, args):
> + """
> + Wrapper for _drive_add method
> + """
> + self._drive_add(args.id, args.guest, args.target)
> +
> + def fullbackup_wrapper(self, args):
> + """
> + Wrapper for _full_backup method
> + """
> + self._full_backup(args.guest)
> +
> + def restore_wrapper(self, args):
> + """
> + Wrapper for restore
> + """
> + self._restore(args.guest)
> +
> +
> +def main():
> + backup_tool = BackupTool()
> + parser = ArgumentParser()
The following is a pretty big block without much visual structure to
guide the eye. I'd recommend:
(1) Splitting this out into a helper function so the overall flow of
main() is easier to spot at a glance, and
(2) Adding a few comments to just visually break up the monotony.
> + subparsers = parser.add_subparsers(title='Subcommands',
> + description='Valid Subcommands',
> + help='Subcommand help') # guest
> + guest_parser = subparsers.add_parser('guest', help='Adds or \
> + removes and lists guest(s)')
Try "Manage guest(s)" as a shorthand, or just write "add, remove, or
list guests."
"Adds (or) removes (and) lists" is an awkward construct.
> + guest_subparsers = guest_parser.add_subparsers(title='Guest Subparser')
# guest list
> + guest_list_parser = guest_subparsers.add_parser('list',
> + help='Lists all guests')
> + guest_list_parser.set_defaults(func=backup_tool.list)
> +
# guest add
> + guest_add_parser = guest_subparsers.add_parser('add', help='Adds a guest')
> + guest_add_parser.add_argument('--guest', action='store', type=str,
> + help='Name of the guest')
> + guest_add_parser.add_argument('--qmp', action='store', type=str,
> + help='Path of socket')
> + guest_add_parser.set_defaults(func=backup_tool.guest_add_wrapper)
> +
# guest remove
> + guest_remove_parser = guest_subparsers.add_parser('remove',
> + help='removes a guest')
> + guest_remove_parser.add_argument('--guest', action='store', type=str,
> + help='Name of the guest')
> + guest_remove_parser.set_defaults(func=backup_tool.guest_remove_wrapper)
> +
# drive
> + drive_parser = subparsers.add_parser('drive',
> + help='Adds drive(s) for backup')
> + drive_subparsers = drive_parser.add_subparsers(title='Add subparser',
> + description='Drive \
> + subparser')
# drive add
> + drive_add_parser = drive_subparsers.add_parser('add',
> + help='Adds new \
> + drive for backup')
> + drive_add_parser.add_argument('--guest', action='store',
> + type=str, help='Name of the guest')
> + drive_add_parser.add_argument('--id', action='store',
> + type=str, help='Drive ID')
> + drive_add_parser.add_argument('--target', nargs='?',
> + default=None, help='Destination path')
> + drive_add_parser.set_defaults(func=backup_tool.drive_add_wrapper)
> +
# backup
> + backup_parser = subparsers.add_parser('backup', help='Creates backup')
> + backup_parser.add_argument('--guest', action='store',
> + type=str, help='Name of the guest')
> + backup_parser.set_defaults(func=backup_tool.fullbackup_wrapper)
> +
# restore
> + backup_parser = subparsers.add_parser('restore', help='Restores drives')
> + backup_parser.add_argument('--guest', action='store',
> + type=str, help='Name of the guest')
> + backup_parser.set_defaults(func=backup_tool.restore_wrapper)
> +
maybe something like:
parser = buildMyParser()
?
> + args = parser.parse_args()
> + args.func(args)
> +
> +if __name__ == '__main__':
> + main()
>
Looking good overall; my advice is to try testing your tool by
intentionally omitting items and giving it bad information. Make sure
that any arguments marked as mandatory in the manpage/parser are
actually mandatory and try to eliminate stack trace dumps from your
python tool.
I stopped a little short of reviewing the entire tool this time, so
there may be more cases that are similar to the other issues I've
already pointed out.
Thanks!
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v3 1/3] backup: QEMU Backup Tool
2017-09-01 22:47 ` John Snow
@ 2017-09-08 11:06 ` Ishani
0 siblings, 0 replies; 7+ messages in thread
From: Ishani @ 2017-09-08 11:06 UTC (permalink / raw)
To: jsnow; +Cc: qemu-devel, famz, stefanha
----- On Sep 2, 2017, at 4:17 AM, jsnow jsnow@redhat.com wrote:
> I suggest as your commit message here, something like:
>
> "backup: Add QEMU backup tool"
>
> A good commit message should say what applying the patch will do:
>
> "What will happen if I apply this patch?"
> "It will 'Add QEMU backup tool'"
>
> On 08/30/2017 01:14 PM, Ishani Chugh wrote:
>> qemu-backup will be a command-line tool for performing full and
>> incremental disk backups on running VMs. It is intended as a
>> reference implementation for management stack and backup developers
>> to see QEMU's backup features in action. The tool writes details of
>> guest in a configuration file and the data is retrieved from the file
>> while creating a backup. The location of config file can be set as an
>> environment variable QEMU_BACKUP_CONFIG. The usage is as follows:
>>
>> Add a guest
>> python qemu-backup.py guest add --guest <guest_name> --qmp <socket_path>
>>
>
> This should probably be organized by subcommand, so:
>
> guest add
> guest remove
> guest list
>
> drive add
>
> backup
>
> restore
>
Will fix in next revision.
>> Add a drive for backup in a specified guest
>> python qemu-backup.py drive add --guest <guest_name> --id <drive_id> [--target
>> <target_file_path>]
>>
>> Create backup of the added drives:
>> python qemu-backup.py backup --guest <guest_name>
>>
>> List all guest configs in configuration file:
>> python qemu-backup.py guest list
>>
>> Restore operation
>> python qemu-backup.py restore --guest <guest-name>
>>
>> Remove a guest
>> python qemu-backup.py guest remove --guest <guest_name>
>>
>
> Looks good, but the man page should perhaps be patch 01 instead of 03 so
> that the usage can be reviewed outside of the commit message.
I will reorder the patches in version 4 with:
1) Manpage
2) Full Backup
3) Test for full backup
>> Signed-off-by: Ishani Chugh <chugh.ishani@research.iiit.ac.in>
>> ---
>> contrib/backup/qemu-backup.py | 343 ++++++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 343 insertions(+)
>> create mode 100644 contrib/backup/qemu-backup.py
>>
>> diff --git a/contrib/backup/qemu-backup.py b/contrib/backup/qemu-backup.py
>> new file mode 100644
>> index 0000000..248ca9f
>> --- /dev/null
>> +++ b/contrib/backup/qemu-backup.py
>> @@ -0,0 +1,343 @@
>> +#!/usr/bin/python
>> +# -*- coding: utf-8 -*-
>> +#
>> +# Copyright (C) 2017 Ishani Chugh <chugh.ishani@research.iiit.ac.in>
>> +#
>> +# 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/>.
>> +#
>> +
>> +"""
>> +This file is an implementation of backup tool
>> +"""
>> +from __future__ import print_function
>> +from argparse import ArgumentParser
>> +import os
>> +import errno
>> +from socket import error as socket_error
>> +try:
>> + import configparser
>> +except ImportError:
>> + import ConfigParser as configparser
>> +import sys
>> +sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..',
>> + 'scripts', 'qmp'))
>> +from qmp import QEMUMonitorProtocol
>> +
>> +
>> +class BackupTool(object):
>> + """BackupTool Class"""
>> + def __init__(self, config_file=os.path.expanduser('~') +
>> + '/.config/qemu/qemu-backup-config'):
>> + if "QEMU_BACKUP_CONFIG" in os.environ:
>> + self.config_file = os.environ["QEMU_BACKUP_CONFIG"]
>> +
>> + else:
>> + self.config_file = config_file
>> + try:
>> + if not os.path.isdir(os.path.dirname(self.config_file)):
>> + os.makedirs(os.path.dirname(self.config_file))
>> + except:
>> + print("Cannot create config directory", file=sys.stderr)
>> + sys.exit(1)
>> + self.config = configparser.ConfigParser()
>> + self.config.read(self.config_file)
>> + try:
>> + if self.config.get('general', 'version') != '1.0':
>> + print("Version Conflict in config file", file=sys.stderr)
>> + sys.exit(1)
>> + except:
>> + self.config['general'] = {'version': '1.0'}
>> + self.write_config()
>> +
>> + def write_config(self):
>> + """
>> + Writes configuration to ini file.
>> + """
>> + config_file = open(self.config_file + ".tmp", 'w')
>> + self.config.write(config_file)
>> + config_file.flush()
>> + os.fsync(config_file.fileno())
>> + config_file.close()
>> + os.rename(self.config_file + ".tmp", self.config_file)
>> +
>> + def get_socket_address(self, socket_address):
>> + """
>> + Return Socket address in form of string or tuple
>> + """
>> + if socket_address.startswith('tcp'):
>> + return (socket_address.split(':')[1],
>> + int(socket_address.split(':')[2]))
>> + return socket_address.split(':', 2)[1]
>> +
>> + def _full_backup(self, guest_name):
>> + """
>> + Performs full backup of guest
>> + """
>> + if guest_name not in self.config.sections():
>> + print("Cannot find specified guest", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + self.verify_guest_running(guest_name)
>> + connection = QEMUMonitorProtocol(
>> + self.get_socket_address(
>> + self.config[guest_name]['qmp']))
>> + connection.connect()
>> + cmd = {"execute": "transaction", "arguments": {"actions": []}}
>> + drive_list = []
>> + for key in self.config[guest_name]:
>> + if key.startswith("drive_"):
>> + drive = key[len('drive_'):]
>> + drive_list.append(drive)
>> + target = self.config[guest_name][key]
>> + sub_cmd = {"type": "drive-backup", "data": {"device": drive,
>> + "target": target,
>> + "sync": "full"}}
>> + cmd['arguments']['actions'].append(sub_cmd)
>> + qmp_return = connection.cmd_obj(cmd)
>> + if 'error' in qmp_return:
>> + print(qmp_return['error']['desc'], file=sys.stderr)
>> + sys.exit(1)
>> + print("Backup Started")
>> + while drive_list:
>> + event = connection.pull_event(wait=True)
>> + if event['event'] == 'SHUTDOWN':
>> + print("The guest was SHUT DOWN", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + if event['event'] == 'BLOCK_JOB_COMPLETED':
>> + if event['data']['device'] in drive_list and \
>> + event['data']['type'] == 'backup':
>> + print("*" + event['data']['device'])
>> + drive_list.remove(event['data']['device'])
>> +
>> + if event['event'] == 'BLOCK_JOB_ERROR':
>> + if event['data']['device'] in drive_list and \
>> + event['data']['type'] == 'backup':
>> + print(event['data']['device'] + " Backup Failed",
>> + file=sys.stderr)
>> + drive_list.remove(event['data']['device'])
>> + print("Backup Complete")
>> +
>> + def _drive_add(self, drive_id, guest_name, target=None):
>> + """
>> + Adds drive for backup
>> + """
>> + if target is None:
>> + target = os.path.abspath(drive_id)
>
> Similar problem as with other commands:
>
> jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py drive add
> Traceback (most recent call last):
> File "./qemu-backup.py", line 343, in <module>
> main()
> File "./qemu-backup.py", line 340, in main
> args.func(args)
> File "./qemu-backup.py", line 272, in drive_add_wrapper
> self._drive_add(args.id, args.guest, args.target)
> File "./qemu-backup.py", line 137, in _drive_add
> target = os.path.abspath(drive_id)
> File "/usr/lib64/python2.7/posixpath.py", line 360, in abspath
> if not isabs(path):
> File "/usr/lib64/python2.7/posixpath.py", line 54, in isabs
> return s.startswith('/')
> AttributeError: 'NoneType' object has no attribute 'startswith'
>
> This errors out if you don't tell it what drive you want to add.
>
>
> Meanwhile,
>
> jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py drive add --id
> foobar
> Cannot find specified guest
>
> Should probably error out because you didn't set the guest name at all.
>
>> +
>> + if os.path.isdir(os.path.dirname(target)) is False:
>> + print("Cannot find target directory", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + if guest_name not in self.config.sections():
>> + print("Cannot find specified guest", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + if "drive_" + drive_id in self.config[guest_name]:
>> + print("Drive already marked for backup", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + self.verify_guest_running(guest_name)
>> +
>> + connection = QEMUMonitorProtocol(
>> + self.get_socket_address(
>> + self.config[guest_name]['qmp']))
>> + connection.connect()
>> + cmd = {'execute': 'query-block'}
>> + returned_json = connection.cmd_obj(cmd)
>> + device_present = False
>> + for device in returned_json['return']:
>> + if device['device'] == drive_id:
>> + device_present = True
>> + break
>> +
>> + if not device_present:
>> + print("No such drive in guest", file=sys.stderr)
>> + sys.exit(1)
>
> cool!
>
>> +
>> + drive_id = "drive_" + drive_id
>> + for d_id in self.config[guest_name]:
>> + if self.config[guest_name][d_id] == target:
>> + print("Please choose different target", file=sys.stderr)
>> + sys.exit(1)
>> + self.config.set(guest_name, drive_id, target)
>> + self.write_config()
>> + print("Successfully Added Drive")
>> +
>> + def verify_guest_running(self, guest_name):
>> + """
>> + Checks whether specified guest is running or not
>> + """
>> + socket_address = self.config.get(guest_name, 'qmp')> + try:
>> + connection = QEMUMonitorProtocol(self.get_socket_address(
>> + socket_address))
>> + connection.connect()
>> + except socket_error:
>> + if socket_error.errno != errno.ECONNREFUSED:
>
> what happens if errno *IS* ECONNREFUSED?
>
>> + print("Connection to guest refused", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + def _guest_add(self, guest_name, socket_address):
>> + """
>> + Adds a guest to the config file
>> + """
>> + if guest_name in self.config.sections():
>> + print("ID already exists. Please choose a different guest name",
>> + file=sys.stderr)
>> + sys.exit(1)
>> + self.config[guest_name] = {'qmp': socket_address}
>> + self.verify_guest_running(guest_name)
>> + self.write_config()
>> + print("Successfully Added Guest")
>
> this function crashes if you do not provide a guest_name, it should
> report an error instead.
>
> ./qemu-backup.py guest add
> ./qemu-backup.py guest add --guest foobar
>
> both crash, please correct.
>
> ./qemu-backup.py guest add --guest foobar --qmp foobar
>
> also crashes, please error gracefully if you cannot parse the QMP
> argument as a valid socket.
I will set the required options to True for mandatory arguments.
>> +
>> + def _guest_remove(self, guest_name):
>> + """
>> + Removes a guest from config file
>> + """
>> + if guest_name not in self.config.sections():
>> + print("Guest Not present", file=sys.stderr)
>> + sys.exit(1)
>> + self.config.remove_section(guest_name)
>> + print("Guest successfully deleted")
>> +
>
> If you don't supply a guest name, you get the "Guest Not present" error
> message, but really we should error out as if it was a parsing error.
>
> jhuston@probe (review) ~/s/q/c/backup> ./qemu-backup.py guest remove
> --guest general
> Guest successfully deleted
>
> Whoops!
>
>> + def _restore(self, guest_name):
>> + """
>> + Prints Steps to perform restore operation
>> + """
>> + if guest_name not in self.config.sections():
>> + print("Cannot find specified guest", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + self.verify_guest_running(guest_name)
>> + connection = QEMUMonitorProtocol(
>> + self.get_socket_address(
>> + self.config[guest_name]['qmp']))
>> + connection.connect()
>> + print("To perform restore:")
>> + print("Shut down guest")
>> + for key in self.config[guest_name]:
>> + if key.startswith("drive_"):
>> + drive = key[len('drive_'):]
>> + target = self.config[guest_name][key]
>> + cmd = {'execute': 'query-block'}
>> + returned_json = connection.cmd_obj(cmd)
>> + device_present = False
>> + for device in returned_json['return']:
>> + if device['device'] == drive:
>> + device_present = True
>> + location = device['inserted']['image']['filename']
>> + print("qemu-img convert " + target + " " + location)
>> +
>> + if not device_present:
>> + print("No such drive in guest", file=sys.stderr)
>> + sys.exit(1)
>> +
>> + def guest_remove_wrapper(self, args):
>> + """
>> + Wrapper for _guest_remove method.
>> + """
>> + guest_name = args.guest
>> + self._guest_remove(guest_name)
>> + self.write_config()
>> +
>> + def list(self, args):
>> + """
>> + Prints guests present in Config file
>> + """
>> + for guest_name in self.config.sections():
>> + print(guest_name)
>
> This will print out "general" too, which I think should be exempted from
> this list, as it is not actually a guest!
>
> I propose something like this:
>
> [general]
> guests=ishanivm1 ishanivm2 ishanivm3
>
> [guest:ishanivm]
> foo=bar
>
> [guest:ishanivm2]
> foo=bar2
>
> and so on.
>
> ("What happens if someone tries to name a guest 'guest:foobar'? Well,
> then the section just gets named 'guest:guest:foobar' and we go about
> our happy way.")
>
> Whenever a guest is added or removed, you update the list and delete or
> add the corresponding section appropriately.
The section general will contain the version number. Will it not be better
to add an additional condition to skip 'general' rather than modifying the
design of config file?
>> +
>> + def guest_add_wrapper(self, args):
>> + """
>> + Wrapper for _quest_add method
>
> s/quest/guest/
Will fix in next revision.
>> + """
>> + self._guest_add(args.guest, args.qmp)
>> +> + def drive_add_wrapper(self, args):
>> + """
>> + Wrapper for _drive_add method
>> + """
>> + self._drive_add(args.id, args.guest, args.target)
>> +
>> + def fullbackup_wrapper(self, args):
>> + """
>> + Wrapper for _full_backup method
>> + """
>> + self._full_backup(args.guest)
>> +
>> + def restore_wrapper(self, args):
>> + """
>> + Wrapper for restore
>> + """
>> + self._restore(args.guest)
>> +
>> +
>> +def main():
>> + backup_tool = BackupTool()
>> + parser = ArgumentParser()
>
> The following is a pretty big block without much visual structure to
> guide the eye. I'd recommend:
>
> (1) Splitting this out into a helper function so the overall flow of
> main() is easier to spot at a glance, and
> (2) Adding a few comments to just visually break up the monotony.
>
>> + subparsers = parser.add_subparsers(title='Subcommands',
>> + description='Valid Subcommands',
>> + help='Subcommand help') # guest
>> + guest_parser = subparsers.add_parser('guest', help='Adds or \
>> + removes and lists guest(s)')
>
> Try "Manage guest(s)" as a shorthand, or just write "add, remove, or
> list guests."
>
> "Adds (or) removes (and) lists" is an awkward construct.
>
>> + guest_subparsers = guest_parser.add_subparsers(title='Guest Subparser')
> # guest list
>> + guest_list_parser = guest_subparsers.add_parser('list',
>> + help='Lists all guests')
>> + guest_list_parser.set_defaults(func=backup_tool.list)
>> +
> # guest add
>> + guest_add_parser = guest_subparsers.add_parser('add', help='Adds a guest')
>> + guest_add_parser.add_argument('--guest', action='store', type=str,
>> + help='Name of the guest')
>> + guest_add_parser.add_argument('--qmp', action='store', type=str,
>> + help='Path of socket')
>> + guest_add_parser.set_defaults(func=backup_tool.guest_add_wrapper)
>> +
> # guest remove
>> + guest_remove_parser = guest_subparsers.add_parser('remove',
>> + help='removes a guest')
>> + guest_remove_parser.add_argument('--guest', action='store', type=str,
>> + help='Name of the guest')
>> + guest_remove_parser.set_defaults(func=backup_tool.guest_remove_wrapper)
>> +
> # drive
>> + drive_parser = subparsers.add_parser('drive',
>> + help='Adds drive(s) for backup')
>> + drive_subparsers = drive_parser.add_subparsers(title='Add subparser',
>> + description='Drive \
>> + subparser')
> # drive add
>> + drive_add_parser = drive_subparsers.add_parser('add',
>> + help='Adds new \
>> + drive for backup')
>> + drive_add_parser.add_argument('--guest', action='store',
>> + type=str, help='Name of the guest')
>> + drive_add_parser.add_argument('--id', action='store',
>> + type=str, help='Drive ID')
>> + drive_add_parser.add_argument('--target', nargs='?',
>> + default=None, help='Destination path')
>> + drive_add_parser.set_defaults(func=backup_tool.drive_add_wrapper)
>> +
> # backup
>> + backup_parser = subparsers.add_parser('backup', help='Creates backup')
>> + backup_parser.add_argument('--guest', action='store',
>> + type=str, help='Name of the guest')
>> + backup_parser.set_defaults(func=backup_tool.fullbackup_wrapper)
>> +
> # restore
>> + backup_parser = subparsers.add_parser('restore', help='Restores drives')
>> + backup_parser.add_argument('--guest', action='store',
>> + type=str, help='Name of the guest')
>> + backup_parser.set_defaults(func=backup_tool.restore_wrapper)
>> +
>
> maybe something like:
> parser = buildMyParser()
>
> ?
Will fix in next revision. I have also identified that
./qemu-backup.py guest add -h
shows every argument as optional argument(even when they are set to required).
I will also fix it in v4.
>> + args = parser.parse_args()
>> + args.func(args)
>> +
>> +if __name__ == '__main__':
>> + main()
>>
>
> Looking good overall; my advice is to try testing your tool by
> intentionally omitting items and giving it bad information. Make sure
> that any arguments marked as mandatory in the manpage/parser are
> actually mandatory and try to eliminate stack trace dumps from your
> python tool.
>
> I stopped a little short of reviewing the entire tool this time, so
> there may be more cases that are similar to the other issues I've
> already pointed out.
>
> Thanks!
Thanks for review.
Regards,
Ishani
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2017-09-08 11:07 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-08-30 17:14 [Qemu-devel] [PATCH v3 0/3] QEMU Backup Tool Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 1/3] backup: " Ishani Chugh
2017-09-01 22:47 ` John Snow
2017-09-08 11:06 ` Ishani
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 2/3] Test for full Backup Ishani Chugh
2017-08-30 17:14 ` [Qemu-devel] [PATCH v3 3/3] Add manpage for QEMU Backup Tool Ishani Chugh
2017-08-31 1:09 ` [Qemu-devel] [PATCH v3 0/3] " Fam Zheng
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