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>
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>
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>
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>
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>
In truth, if you don't do this, you'll just get a TypeError
exception. Now, you'll get an AssertionError.
Is this tangibly better? No.
Does mypy complain less? Yes.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200514055403.18902-21-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
mypy considers it incorrect to use `bool` to statically return false,
because it will assume that it could conceivably return True, and gives
different analysis in that case. Use a None return to achieve the same
effect, but make mypy happy.
Note: Pylint considers function signatures as code that might trip the
duplicate-code checker. I'd rather not disable this as it does not
trigger often in practice, so I'm disabling it as a one-off and filed a
change request; see https://github.com/PyCQA/pylint/issues/3619
Signed-off-by: John Snow <jsnow@redhat.com>
Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200514055403.18902-14-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Mostly, ignore the "no bare except" rule, because flake8 is not
contextual and cannot determine if we re-raise. Pylint can, though, so
always prefer pylint for that.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200528222129.23826-5-jsnow@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
In case qemu process dies the "monitor.cmd" returns None which gets
passed to the "__negotiate_capabilities" and leads to unhandled
exception. Let's only check the resp in case it has a value.
Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Message-Id: <20200120071202.30646-1-ldoktor@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
This implement the __enter__ and __exit__ functions on
QEMUMonitorProtocol class so that it can be used on 'with'
statement and the resources will be free up on block end:
with QEMUMonitorProtocol(socket_path) as qmp:
qmp.connect()
qmp.command('query-status')
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-Id: <20200204141111.3207-5-wainersm@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Currently the timeout of QEMUMonitorProtocol.accept() is
hard-coded to 15.0 seconds. This added the parameter `timeout`
so the value can be configured by the user.
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-Id: <20200204141111.3207-4-wainersm@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
This clean up the pylint-3 report on qmp:
************* Module qemu.qmp
python/qemu/qmp.py:1:0: C0111: Missing module docstring (missing-docstring)
python/qemu/qmp.py:17:0: C0111: Missing class docstring (missing-docstring)
python/qemu/qmp.py:21:0: C0111: Missing class docstring (missing-docstring)
python/qemu/qmp.py:25:0: C0111: Missing class docstring (missing-docstring)
python/qemu/qmp.py:29:0: C0111: Missing class docstring (missing-docstring)
python/qemu/qmp.py:33:0: C0111: Missing class docstring (missing-docstring)
python/qemu/qmp.py:33:0: R0205: Class 'QEMUMonitorProtocol' inherits from object, can be safely removed from bases in python3 (useless-object-inheritance)
python/qemu/qmp.py:80:4: R1710: Either all return statements in a function should return an expression, or none of them should. (inconsistent-return-statements)
python/qemu/qmp.py:131:4: R1710: Either all return statements in a function should return an expression, or none of them should. (inconsistent-return-statements)
python/qemu/qmp.py:159:4: R1710: Either all return statements in a function should return an expression, or none of them should. (inconsistent-return-statements)
python/qemu/qmp.py:245:4: C0111: Missing method docstring (missing-docstring)
python/qemu/qmp.py:249:4: C0111: Missing method docstring (missing-docstring)
python/qemu/qmp.py:252:4: C0111: Missing method docstring (missing-docstring)
python/qemu/qmp.py:255:4: C0111: Missing method docstring (missing-docstring)
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20191227134101.244496-3-wainersm@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
This is a simple move of Python code that wraps common QEMU
functionality, and are used by a number of different tests
and scripts.
By treating that code as a real Python module, we can more easily:
* reuse code
* have a proper place for the module's own unittests
* apply a more consistent style
* generate documentation
Signed-off-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Caio Carrara <ccarrara@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190206162901.19082-2-crosa@redhat.com>
Signed-off-by: Cleber Rosa <crosa@redhat.com>
