Commit graph

93 commits

Author SHA1 Message Date
John Snow 81f8c4467c python: move flake8 config to setup.cfg
Update the comment concerning the flake8 exception to match commit
42c0dd12, whose commit message stated:

A note on the flake8 exception: flake8 will warn on *any* bare except,
but pylint's is context-aware and will suppress the warning if you
re-raise the exception.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-19-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow ef42440d79 python: move pylintrc into setup.cfg
Delete the empty settings now that it's sharing a home with settings for
other tools.

pylint can now be run from this folder as "pylint qemu".

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-17-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow d1e0476958 python: add pylint import exceptions
Pylint 2.5.x - 2.7.x have regressions that make import checking
inconsistent, see:

https://github.com/PyCQA/pylint/issues/3609
https://github.com/PyCQA/pylint/issues/3624
https://github.com/PyCQA/pylint/issues/3651

Pinning to 2.4.4 is worse, because it mandates versions of shared
dependencies that are too old for features we want in isort and mypy.
Oh well.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-16-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 93128815af python: add directory structure README.rst files
Add short readmes to python/, python/qemu/, python/qemu/machine,
python/qemu/qmp, and python/qemu/utils that explain the directory
hierarchy. These readmes are visible when browsing the source on
e.g. gitlab/github and are designed to help new developers/users quickly
make sense of the source tree.

They are not designed for inclusion in a published manual.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-13-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow beb6b57b3b python: create qemu packages
move python/qemu/*.py to python/qemu/[machine, qmp, utils]/*.py and
update import directives across the tree.

This is done to create a PEP420 namespace package, in which we may
create subpackages. To do this, the namespace directory ("qemu") should
not have any modules in it. Those files will go into new 'machine',
'qmp' and 'utils' subpackages instead.

Implement machine/__init__.py making the top-level classes and functions
from its various modules available directly inside the package. Change
qmp.py to qmp/__init__.py similarly, such that all of the useful QMP
library classes are available directly from "qemu.qmp" instead of
"qemu.qmp.qmp".

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 859aeb67d7 python/machine: Trim line length to below 80 chars
One more little delinting fix that snuck in.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow a0eae17a59 python/machine: disable warning for Popen in _launch()
We handle this resource rather meticulously in
shutdown/kill/wait/__exit__ et al, through the laborious mechanisms in
_do_shutdown().

Quiet this pylint warning here.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-7-jsnow@redhat.com
Message-id: 20210517184808.3562549-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 63c33f3c28 python/machine: Disable pylint warning for open() in _pre_launch
Shift the open() call later so that the pylint pragma applies *only* to
that one open() call. Add a note that suggests why this is safe: the
resource is unconditionally cleaned up in _post_shutdown().

_post_shutdown is called after failed launches (see launch()), and
unconditionally after every call to shutdown(), and therefore also on
__exit__.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-6-jsnow@redhat.com
Message-id: 20210517184808.3562549-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 8825fed82a python/console_socket: Add a pylint ignore
We manage cleaning up this resource ourselves. Pylint should shush.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-5-jsnow@redhat.com
Message-id: 20210517184808.3562549-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 14b41797d5 python/machine: use subprocess.run instead of subprocess.Popen
use run() instead of Popen() -- to assert to pylint that we are not
forgetting to close a long-running program.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-4-jsnow@redhat.com
Message-id: 20210517184808.3562549-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow 07b71233a7 python/machine: use subprocess.DEVNULL instead of open(os.path.devnull)
One less file resource to manage, and it helps quiet some pylint >=
2.8.0 warnings about not using a with-context manager for the open call.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-3-jsnow@redhat.com
Message-id: 20210517184808.3562549-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
John Snow ee1a27235b python/console_socket: avoid one-letter variable
Fixes pylint warnings.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210527211715.394144-2-jsnow@redhat.com
Message-id: 20210517184808.3562549-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00
Cleber Rosa 976218cbe7 Python: add utility function for retrieving port redirection
Slightly different versions for the same utility code are currently
present on different locations.  This unifies them all, giving
preference to the version from virtiofs_submounts.py, because of the
last tweaks added to it.

While at it, this adds a "qemu.utils" module to host the utility
function and a test.

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20210412044644.55083-4-crosa@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
[Squashed in below fix. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20210601154546.130870-2-crosa@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:20 -04:00
Cleber Rosa 2ca6e26cea Python: expose QEMUMachine's temporary directory
Each instance of qemu.machine.QEMUMachine currently has a "test
directory", which may not have any relation to a "test", and it's
really a temporary directory.

Users instantiating the QEMUMachine class will be able to set the
location of the directory that will *contain* the QEMUMachine unique
temporary directory, so that parameter name has been changed from
test_dir to base_temp_dir.

A property has been added to allow users to access it without using
private attributes, and with that, the directory is created on first
use of the property.

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20210211220146.2525771-3-crosa@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Cleber Rosa <crosa@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:20 -04:00
Cleber Rosa 3c1e16c60c Python: close the log file kept by QEMUMachine before reading it
Closing a file that is open for writing, and then reading from it
sounds like a better idea than the opposite, given that the content
will be flushed.

Reference: https://docs.python.org/3/library/io.html#io.IOBase.close
Signed-off-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20210211220146.2525771-2-crosa@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Cleber Rosa <crosa@redhat.com>
2021-02-15 21:40:16 -05:00
Alex Bennée afded359a6 python: add __repr__ to ConsoleSocket to aid debugging
While attempting to debug some console weirdness I thought it would be
worth making it easier to see what it had inside.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20201210190417.31673-6-alex.bennee@linaro.org>
2021-01-02 21:03:09 +01:00
Paolo Bonzini 991c180d74 treewide: do not use short-form boolean options
They are going to be deprecated, avoid warnings on stdout while the
tests run.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:11 -05:00
Alex Bennée 8c175c63ee tests: add prefixes to the bare mkdtemp calls
The first step to debug a thing is to know what created the thing in
the first place. Add some prefixes so random tmpdir's have something
grep in the code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201117173635.29101-3-alex.bennee@linaro.org>
2020-11-23 09:51:43 +00:00
John Snow 39cf73c349 python/qemu/qmp.py: Fix settimeout operation
We enabled callers to interface directly with settimeout, but this
reacts poorly with blocking/nonblocking operation; as they are using the
same internal mechanism.

1. Whenever we change the blocking mechanism temporarily, always set it
back to what it was afterwards.

2. Disallow callers from setting a timeout of "0", which means
Non-blocking mode. This is going to create more weird problems than
anybody wants, so just forbid it.

I opt not to coerce '0' to 'None' to maintain the principal of least
surprise in mirroring the semantics of Python's interface.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201009175123.249009-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 15:00:06 -04:00
John Snow d5cca076c3 python/qemu/qmp.py: re-raise OSError when encountered
Nested if conditions don't change when the exception block fires; we
need to explicitly re-raise the error if we didn't intend to capture and
suppress it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201009175123.249009-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 14:58:47 -04:00
John Snow d2b08b79b0 python/qemu/qmp.py: Preserve error context on re-raise
Use the "from ..." phrasing when re-raising errors to preserve their
initial context, to help aid debugging when things go wrong.

This also silences a pylint 2.6.0+ error.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-18-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow af0db88254 python/qemu/console_socket.py: avoid encoding to/from string
We can work directly in bytes instead of translating back and forth to
string, which removes the question of which encodings to use.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-17-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow e35c138267 python/qemu/console_socket.py: Add type hint annotations
Finish the typing of console_socket.py with annotations and no code
changes.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-16-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 714ac05a19 python/qemu/console_socket.py: Clarify type of drain_thread
Mypy needs just a little help to guess the type here.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-15-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 6cf4cce7cb python/qemu/console_socket.py: fix typing of settimeout
The types and names of the parameters must match the socket.socket interface.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-14-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow ff3513e632 python/qemu/console_socket.py: Correct type of recv()
The type and parameter names of recv() should match socket.socket().

OK, easy enough, but in the cases we don't pass straight through to the
real socket implementation, we probably can't accept such flags. OK, for
now, assert that we don't receive flags in such cases.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-13-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow f12a282ff4 python/qemu: Add mypy type annotations
These should all be purely annotations with no changes in behavior at
all. You need to be in the python folder, but you should be able to
confirm that these annotations are correct (or at least self-consistent)
by running `mypy --strict qemu`.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-12-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow aad3f3bb6c python/qemu: make 'args' style arguments immutable
These arguments don't need to be mutable and aren't really used as
such. Clarify their types as immutable and adjust code to match where
necessary.

In general, It's probably best not to accept a user-defined mutable
object and store it as internal object state unless there's a strong
justification for doing so. Instead, try to use generic types as input
with empty tuples as the default, and coerce to list where necessary.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201006235817.3280413-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 9223fda464 python/machine.py: fix _popen access
As always, Optional[T] causes problems with unchecked access. Add a
helper that asserts the pipe is present before we attempt to talk with
it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-9-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow be1183e52f python/machine.py: Add _qmp access shim
Like many other Optional[] types, it's not always a given that this
object will be set. Wrap it in a type-shim that raises a meaningful
error and will always return a concrete type.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow aaa81ec609 python/machine.py: use qmp.command
machine.py and qmp.py both do the same thing here; refactor machine.py
to use qmp.py's functionality more directly.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201006235817.3280413-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 1847a4a8c2 python/machine.py: Handle None events in events_wait
If the timeout is 0, we can get None back. Handle this explicitly.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 652809dfa6 python/machine.py: Don't modify state in _base_args()
Don't append to the _remove_files list during _base_args; instead do so
during _launch. Rework _base_args as a @property to help facilitate
this impression.

This has the additional benefit of making the type of _console_address
easier to analyze statically.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow c5e61a6da8 python/machine.py: reorder __init__
Put the init arg handling all at the top, and mostly in order (deviating
when one is dependent on another), and put what is effectively runtime
state declaration at the bottom.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow c4e6023f05 python/machine.py: Fix monitor address typing
Prior to this, it's difficult for mypy to intuit what the concrete type
of the monitor address is; it has difficulty inferring the type across
two variables.

Create _monitor_address as a property that always returns a valid
address to simplify static type analysis.

To preserve our ability to clean up, use a simple boolean to indicate
whether or not we should try to clean up the sock file after execution.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
John Snow 932ca4bbde python/qemu: use isort to lay out imports
Borrowed from the QAPI cleanup series, use the same configuration to
standardize the way we write and sort imports.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20201006235817.3280413-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2020-10-20 09:37:57 -04:00
Robert Foley 80ded8e99d python/qemu: Change ConsoleSocket to optionally drain socket.
The primary purpose of this change is to clean up
machine.py's console_socket property to return a single type,
a ConsoleSocket.

ConsoleSocket now derives from a socket, which means that
in the default case (of not draining), machine.py
will see the same behavior as it did prior to ConsoleSocket.

Signed-off-by: Robert Foley <robert.foley@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200717203041.9867-3-robert.foley@linaro.org>
Message-Id: <20200724064509.331-16-alex.bennee@linaro.org>
2020-07-27 09:41:56 +01:00
Robert Foley 4b84d87449 python/qemu: Cleanup changes to ConsoleSocket
The changes to console_socket.py and machine.py are to
cleanup for pylint and flake8.

Signed-off-by: Robert Foley <robert.foley@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200717203041.9867-2-robert.foley@linaro.org>
Message-Id: <20200724064509.331-15-alex.bennee@linaro.org>
2020-07-27 09:41:52 +01:00
John Snow 8226a4b88b python/machine: Change default timeout to 30 seconds
3 seconds is too short for some tests running inside busy VMs. Build it out to
a rather generous 30 seconds to find out conclusively if there are more severe
problems in the merge/CI tests.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-id: 20200720160252.104139-2-jsnow@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-25 17:27:10 +01:00
John Snow 84dcdf0887 python/qmp.py: add QMPProtocolError
In the case that we receive a reply but are unable to understand it,
use this exception name to indicate that case.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200710052220.3306-7-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow 2e2d930517 python/qmp.py: add casts to JSON deserialization
mypy and python type hints are not powerful enough to properly describe
JSON messages in Python 3.6. The best we can do, generally, is describe
them as Dict[str, Any].

Add casts to coerce this type for static analysis; but do NOT enforce
this type at runtime in any way.

Note: Python 3.8 adds a TypedDict construct which allows for the
description of more arbitrary Dictionary shapes. There is a third-party
module, "Pydantic", which is compatible with 3.6 that can be used
instead of the JSON library that parses JSON messages to fully-typed
Python objects, and may be preferable in some cases.

(That is well beyond the scope of this commit or series.)

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200710052220.3306-6-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow ef5d474472 python/qmp.py: Do not return None from cmd_obj
This makes typing the qmp library difficult, as it necessitates wrapping
Optional[] around the type for every return type up the stack. At some
point, it becomes difficult to discern or remember why it's None instead
of the expected object.

Use the python exception system to tell us exactly why we didn't get an
object. Remove this special-cased return.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200710052220.3306-5-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow e3a23b4803 python/qmp.py: re-absorb MonitorResponseError
When I initially split this out, I considered this more of a machine
error than a QMP protocol error, but I think that's misguided.

Move this back to qmp.py and name it QMPResponseError. Convert
qmp.command() to use this exception type.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200710052220.3306-4-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow a5d76376d6 python/qmp.py: Define common types
Define some common types that we'll need to annotate a lot of other
functions going forward.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200710052220.3306-2-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow 04f0e36eba python/machine.py: change default wait timeout to 3 seconds
Machine.wait() does not appear to be used except in the acceptance tests,
and an infinite timeout by default in a test suite is not the most helpful.

Change it to 3 seconds, like the default shutdown timeout.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20200710050649.32434-13-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow de6e08b5b9 python/machine.py: re-add sigkill warning suppression
If the user kills QEMU on purpose, we don't need to warn
them about that having happened: they know already.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20200710050649.32434-12-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow 193bf1c061 python/machine.py: split shutdown into hard and soft flavors
This is done primarily to avoid the 'bare except' pattern, which
suppresses all exceptions during shutdown and can obscure errors.

Replace this with a pattern that isolates the different kind of shutdown
paradigms (_hard_shutdown and _soft_shutdown), and a new fallback shutdown
handler (_do_shutdown) that gracefully attempts one before the other.

This split now also ensures that no matter what happens,
_post_shutdown() is always invoked.

shutdown() changes in behavior such that if it attempts to do a graceful
shutdown and is unable to, it will now always raise an exception to
indicate this. This can be avoided by the test writer in three ways:

1. If the VM is expected to have already exited or is in the process of
exiting, wait() can be used instead of shutdown() to clean up resources
instead. This helps avoid race conditions in shutdown.

2. If a test writer is expecting graceful shutdown to fail, shutdown
should be called in a try...except block.

3. If the test writer has no interest in performing a graceful shutdown
at all, kill() can be used instead.

Handling shutdown in this way makes it much more explicit which type of
shutdown we want and allows the library to report problems with this
process.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20200710050649.32434-11-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow 8952805931 python/machine.py: Make wait() call shutdown()
At this point, shutdown(has_quit=True) and wait() do essentially the
same thing; they perform cleanup without actually instructing QEMU to
quit.

Define one in terms of the other.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20200710050649.32434-8-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow c9b3045bc2 python/machine.py: Add a configurable timeout to shutdown()
Three seconds is hardcoded. Use it as a default parameter instead, and use that
value for both waits that may occur in the function.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20200710050649.32434-7-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00
John Snow a3842cb078 python/machine.py: Prohibit multiple shutdown() calls
If the VM is not launched, don't try to shut it down. As a change,
_post_shutdown now unconditionally also calls _early_cleanup in order to
offer comprehensive object cleanup in failure cases.

As a courtesy, treat it as a NOP instead of rejecting it as an
error. This is slightly nicer for acceptance tests where vm.shutdown()
is issued unconditionally in tearDown callbacks.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200710050649.32434-6-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-14 22:22:22 +02:00