* [PATCH v3 1/2] python: introduce qmp-shell-wrap convenience tool
2022-01-28 16:11 [PATCH v3 0/2] python: a few improvements to qmp-shell Daniel P. Berrangé
@ 2022-01-28 16:11 ` Daniel P. Berrangé
2022-01-28 16:11 ` [PATCH v3 2/2] python: support recording QMP session to a file Daniel P. Berrangé
2022-02-07 21:05 ` [PATCH v3 0/2] python: a few improvements to qmp-shell John Snow
2 siblings, 0 replies; 6+ messages in thread
From: Daniel P. Berrangé @ 2022-01-28 16:11 UTC (permalink / raw)
To: qemu-devel
Cc: Eduardo Habkost, Daniel P. Berrangé, John Snow,
Markus Armbruster, Cleber Rosa
With the current 'qmp-shell' tool developers must first spawn QEMU with
a suitable -qmp arg and then spawn qmp-shell in a separate terminal
pointing to the right socket.
With 'qmp-shell-wrap' developers can ignore QMP sockets entirely and
just pass the QEMU command and arguments they want. The program will
listen on a UNIX socket and tell QEMU to connect QMP to that.
For example, this:
# qmp-shell-wrap -- qemu-system-x86_64 -display none
Is roughly equivalent of running:
# qemu-system-x86_64 -display none -qmp qmp-shell-1234 &
# qmp-shell qmp-shell-1234
Except that 'qmp-shell-wrap' switches the socket peers around so that
it is the UNIX socket server and QEMU is the socket client. This makes
QEMU reliably go away when qmp-shell-wrap exits, closing the server
socket.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
python/qemu/aqmp/qmp_shell.py | 67 ++++++++++++++++++++++++++++++++---
python/setup.cfg | 1 +
scripts/qmp/qmp-shell-wrap | 11 ++++++
3 files changed, 75 insertions(+), 4 deletions(-)
create mode 100755 scripts/qmp/qmp-shell-wrap
diff --git a/python/qemu/aqmp/qmp_shell.py b/python/qemu/aqmp/qmp_shell.py
index d11bf54b00..185f5066ef 100644
--- a/python/qemu/aqmp/qmp_shell.py
+++ b/python/qemu/aqmp/qmp_shell.py
@@ -86,6 +86,7 @@
import os
import re
import readline
+from subprocess import Popen
import sys
from typing import (
Iterator,
@@ -167,8 +168,10 @@ class QMPShell(QEMUMonitorProtocol):
:param verbose: Echo outgoing QMP messages to console.
"""
def __init__(self, address: SocketAddrT,
- pretty: bool = False, verbose: bool = False):
- super().__init__(address)
+ pretty: bool = False,
+ verbose: bool = False,
+ server: bool = False):
+ super().__init__(address, server=server)
self._greeting: Optional[QMPMessage] = None
self._completer = QMPCompleter()
self._transmode = False
@@ -409,8 +412,10 @@ class HMPShell(QMPShell):
:param verbose: Echo outgoing QMP messages to console.
"""
def __init__(self, address: SocketAddrT,
- pretty: bool = False, verbose: bool = False):
- super().__init__(address, pretty, verbose)
+ pretty: bool = False,
+ verbose: bool = False,
+ server: bool = False):
+ super().__init__(address, pretty, verbose, server)
self._cpu_index = 0
def _cmd_completion(self) -> None:
@@ -533,5 +538,59 @@ def main() -> None:
pass
+def main_wrap() -> None:
+ """
+ qmp-shell-wrap entry point: parse command line arguments and
+ start the REPL.
+ """
+ parser = argparse.ArgumentParser()
+ parser.add_argument('-H', '--hmp', action='store_true',
+ help='Use HMP interface')
+ parser.add_argument('-v', '--verbose', action='store_true',
+ help='Verbose (echo commands sent and received)')
+ parser.add_argument('-p', '--pretty', action='store_true',
+ help='Pretty-print JSON')
+
+ parser.add_argument('command', nargs=argparse.REMAINDER,
+ help='QEMU command line to invoke')
+
+ args = parser.parse_args()
+
+ cmd = args.command
+ if len(cmd) != 0 and cmd[0] == '--':
+ cmd = cmd[1:]
+ if len(cmd) == 0:
+ cmd = ["qemu-system-x86_64"]
+
+ sockpath = "qmp-shell-wrap-%d" % os.getpid()
+ cmd += ["-qmp", "unix:%s" % sockpath]
+
+ shell_class = HMPShell if args.hmp else QMPShell
+
+ try:
+ address = shell_class.parse_address(sockpath)
+ except qmp.QMPBadPortError:
+ parser.error(f"Bad port number: {sockpath}")
+ return # pycharm doesn't know error() is noreturn
+
+ try:
+ with shell_class(address, args.pretty, args.verbose, True) as qemu:
+ with Popen(cmd):
+
+ try:
+ qemu.accept()
+ except qmp.QMPConnectError:
+ die("Didn't get QMP greeting message")
+ except qmp.QMPCapabilitiesError:
+ die("Couldn't negotiate capabilities")
+ except OSError as err:
+ die(f"Couldn't connect to {sockpath}: {err!s}")
+
+ for _ in qemu.repl():
+ pass
+ finally:
+ os.unlink(sockpath)
+
+
if __name__ == '__main__':
main()
diff --git a/python/setup.cfg b/python/setup.cfg
index 3fb18f845d..84c0f33baf 100644
--- a/python/setup.cfg
+++ b/python/setup.cfg
@@ -68,6 +68,7 @@ console_scripts =
qom-fuse = qemu.utils.qom_fuse:QOMFuse.entry_point [fuse]
qemu-ga-client = qemu.utils.qemu_ga_client:main
qmp-shell = qemu.aqmp.qmp_shell:main
+ qmp-shell-wrap = qemu.aqmp.qmp_shell:main_wrap
aqmp-tui = qemu.aqmp.aqmp_tui:main [tui]
[flake8]
diff --git a/scripts/qmp/qmp-shell-wrap b/scripts/qmp/qmp-shell-wrap
new file mode 100755
index 0000000000..9e94da114f
--- /dev/null
+++ b/scripts/qmp/qmp-shell-wrap
@@ -0,0 +1,11 @@
+#!/usr/bin/env python3
+
+import os
+import sys
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
+from qemu.qmp import qmp_shell
+
+
+if __name__ == '__main__':
+ qmp_shell.main_wrap()
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v3 2/2] python: support recording QMP session to a file
2022-01-28 16:11 [PATCH v3 0/2] python: a few improvements to qmp-shell Daniel P. Berrangé
2022-01-28 16:11 ` [PATCH v3 1/2] python: introduce qmp-shell-wrap convenience tool Daniel P. Berrangé
@ 2022-01-28 16:11 ` Daniel P. Berrangé
2022-02-07 21:05 ` [PATCH v3 0/2] python: a few improvements to qmp-shell John Snow
2 siblings, 0 replies; 6+ messages in thread
From: Daniel P. Berrangé @ 2022-01-28 16:11 UTC (permalink / raw)
To: qemu-devel
Cc: Eduardo Habkost, Daniel P. Berrangé,
Philippe Mathieu-Daudé, Markus Armbruster, Cleber Rosa,
John Snow
When running QMP commands with very large response payloads, it is often
not easy to spot the info you want. If we can save the response to a
file then tools like 'grep' or 'jq' can be used to extract information.
For convenience of processing, we merge the QMP command and response
dictionaries together:
{
"arguments": {},
"execute": "query-kvm",
"return": {
"enabled": false,
"present": true
}
}
Example usage
$ ./scripts/qmp/qmp-shell-wrap -l q.log -p -- ./build/qemu-system-x86_64 -display none
Welcome to the QMP low-level shell!
Connected
(QEMU) query-kvm
{
"return": {
"enabled": false,
"present": true
}
}
(QEMU) query-mice
{
"return": [
{
"absolute": false,
"current": true,
"index": 2,
"name": "QEMU PS/2 Mouse"
}
]
}
$ jq --slurp '. | to_entries[] | select(.value.execute == "query-kvm") |
.value.return.enabled' < q.log
false
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
python/qemu/aqmp/qmp_shell.py | 29 ++++++++++++++++++++++-------
python/setup.cfg | 3 +++
2 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/python/qemu/aqmp/qmp_shell.py b/python/qemu/aqmp/qmp_shell.py
index 185f5066ef..85988d9f2e 100644
--- a/python/qemu/aqmp/qmp_shell.py
+++ b/python/qemu/aqmp/qmp_shell.py
@@ -89,6 +89,7 @@
from subprocess import Popen
import sys
from typing import (
+ IO,
Iterator,
List,
NoReturn,
@@ -170,7 +171,8 @@ class QMPShell(QEMUMonitorProtocol):
def __init__(self, address: SocketAddrT,
pretty: bool = False,
verbose: bool = False,
- server: bool = False):
+ server: bool = False,
+ logfile: Optional[str] = None):
super().__init__(address, server=server)
self._greeting: Optional[QMPMessage] = None
self._completer = QMPCompleter()
@@ -180,6 +182,10 @@ def __init__(self, address: SocketAddrT,
'.qmp-shell_history')
self.pretty = pretty
self.verbose = verbose
+ self.logfile = None
+
+ if logfile is not None:
+ self.logfile = open(logfile, "w", encoding='utf-8')
def close(self) -> None:
# Hook into context manager of parent to save shell history.
@@ -320,11 +326,11 @@ def _build_cmd(self, cmdline: str) -> Optional[QMPMessage]:
self._cli_expr(cmdargs[1:], qmpcmd['arguments'])
return qmpcmd
- def _print(self, qmp_message: object) -> None:
+ def _print(self, qmp_message: object, fh: IO[str] = sys.stdout) -> None:
jsobj = json.dumps(qmp_message,
indent=4 if self.pretty else None,
sort_keys=self.pretty)
- print(str(jsobj))
+ print(str(jsobj), file=fh)
def _execute_cmd(self, cmdline: str) -> bool:
try:
@@ -347,6 +353,9 @@ def _execute_cmd(self, cmdline: str) -> bool:
print('Disconnected')
return False
self._print(resp)
+ if self.logfile is not None:
+ cmd = {**qmpcmd, **resp}
+ self._print(cmd, fh=self.logfile)
return True
def connect(self, negotiate: bool = True) -> None:
@@ -414,8 +423,9 @@ class HMPShell(QMPShell):
def __init__(self, address: SocketAddrT,
pretty: bool = False,
verbose: bool = False,
- server: bool = False):
- super().__init__(address, pretty, verbose, server)
+ server: bool = False,
+ logfile: Optional[str] = None):
+ super().__init__(address, pretty, verbose, server, logfile)
self._cpu_index = 0
def _cmd_completion(self) -> None:
@@ -508,6 +518,8 @@ def main() -> None:
help='Verbose (echo commands sent and received)')
parser.add_argument('-p', '--pretty', action='store_true',
help='Pretty-print JSON')
+ parser.add_argument('-l', '--logfile',
+ help='Save log of all QMP messages to PATH')
default_server = os.environ.get('QMP_SOCKET')
parser.add_argument('qmp_server', action='store',
@@ -526,7 +538,7 @@ def main() -> None:
parser.error(f"Bad port number: {args.qmp_server}")
return # pycharm doesn't know error() is noreturn
- with shell_class(address, args.pretty, args.verbose) as qemu:
+ with shell_class(address, args.pretty, args.verbose, args.logfile) as qemu:
try:
qemu.connect(negotiate=not args.skip_negotiation)
except ConnectError as err:
@@ -550,6 +562,8 @@ def main_wrap() -> None:
help='Verbose (echo commands sent and received)')
parser.add_argument('-p', '--pretty', action='store_true',
help='Pretty-print JSON')
+ parser.add_argument('-l', '--logfile',
+ help='Save log of all QMP messages to PATH')
parser.add_argument('command', nargs=argparse.REMAINDER,
help='QEMU command line to invoke')
@@ -574,7 +588,8 @@ def main_wrap() -> None:
return # pycharm doesn't know error() is noreturn
try:
- with shell_class(address, args.pretty, args.verbose, True) as qemu:
+ with shell_class(address, args.pretty, args.verbose,
+ True, args.logfile) as qemu:
with Popen(cmd):
try:
diff --git a/python/setup.cfg b/python/setup.cfg
index 84c0f33baf..9aeb74aed4 100644
--- a/python/setup.cfg
+++ b/python/setup.cfg
@@ -114,7 +114,10 @@ ignore_missing_imports = True
# no Warning level messages displayed, use "--disable=all --enable=classes
# --disable=W".
disable=consider-using-f-string,
+ consider-using-with,
+ too-many-arguments,
too-many-function-args, # mypy handles this with less false positives.
+ too-many-instance-attributes,
no-member, # mypy also handles this better.
[pylint.basic]
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread