The synchronous QMP library would bind to the server address during
__init__(). The new library delays this to the accept() call, because
binding occurs inside of the call to start_[unix_]server(), which is an
async method -- so it cannot happen during __init__ anymore.
Python 3.7+ adds the ability to create the server (and thus the bind()
call) and begin the active listening in separate steps, but we don't
have that functionality in 3.6, our current minimum.
Therefore ... Add a temporary workaround that allows the synchronous
version of the client to bind the socket in advance, guaranteeing that
there will be a UNIX socket in the filesystem ready for the QEMU client
to connect to without a race condition.
(Yes, it's a bit ugly. Fixing it more nicely will have to wait until our
minimum Python version is 3.7+.)
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20220201041134.1237016-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This is in preparation for renaming qemu.aqmp to qemu.qmp. I should have
done this from this from the very beginning, but it's a convenient time
to make sure this churn is taken care of.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Copy the remaining type definitions from QMP into the qemu.aqmp.legacy
module. Now, users that require the legacy interface don't need to
import anything else but qemu.aqmp.legacy wrapper.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Beraldo Leal <bleal@redhat.com>
0.920 (Released 2021-12-15) is not entirely happy with the
way that I was defining _FutureT:
qemu/aqmp/protocol.py:601: error: Item "object" of the upper bound
"Optional[Future[Any]]" of type variable "_FutureT" has no attribute
"done"
Update it with something a little mechanically simpler that works better
across a wider array of mypy versions.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20220110191349.1841027-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
When ConnectError is used to wrap an Exception that was initialized
without an error message, we are treated to a traceback with a rubbish
line like this:
... ConnectError: Failed to establish session:
Correct this to use the name of an exception as a fallback message:
... ConnectError: Failed to establish session: EOFError
Better!
Signed-off-by: John Snow <jsnow@redhat.com>
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20211111143719.2162525-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
If we receive ConnectionResetError (ECONNRESET) while attempting to
perform capabilities negotiation -- prior to the establishment of the
async reader/writer tasks -- the disconnect function is not aware that
we are in an error pathway.
As a result, when attempting to close the StreamWriter, we'll see the
same ConnectionResetError that caused us to initiate a disconnect in the
first place, which will cause the disconnect task itself to fail, which
emits a CRITICAL logging event.
I still don't know if there's a smarter way to check to see if an
exception received at this point is "the same" exception as the one that
caused the initial disconnect, but for now the problem can be avoided by
improving the error pathway detection in the exit path.
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20211111143719.2162525-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
When we encounter an EOFError, we don't know if it's an "error" in the
perspective of the user of the library yet. Therefore, we should not log
it as an error. Reduce the severity of this logging message to "INFO" to
indicate that it's something that we expect to occur during the normal
operation of the library.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210923004938.3999963-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This is added as a courtesy: many protocols are line-based, including
QMP. Putting it in AsyncProtocol lets us keep the QMP class
implementation just a pinch more abstract.
(And, if we decide to add a QTEST implementation later, it will need
this, too. (Yes, I have a QTEST implementation.))
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-13-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
Add hooks designed to log/filter incoming/outgoing messages. The primary
intent for these is to be able to support iotests which may want to log
messages with specific filters for reproducible output.
Another use is for plugging into Urwid frameworks; all messages in/out
can be automatically added to a rendering list for the purposes of a
qmp-shell like tool.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-12-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
QMP can transmit some pretty big messages, and the default limit of 64KB
isn't sufficient. Make sure that we can configure it.
Reported-by: G S Niteesh Babu <niteesh.gs@gmail.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-11-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
It's a little messier than connect, because it wasn't designed to accept
*precisely one* connection. Such is life.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
Give the connection and the reader/writer tasks nicknames, and add
logging statements throughout.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-9-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This serves a few purposes:
1. Protect interfaces when it's not safe to call them (via @require)
2. Add an interface by which an async client can determine if the state
has changed, for the purposes of connection management.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This is the bare minimum that you need to establish a full-duplex async
message-based protocol with Python's asyncio.
The features to be added in forthcoming commits are:
- Runstate tracking
- Logging
- Support for incoming connections via accept()
- _cb_outbound, _cb_inbound message hooks
- _readline() method
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
John Snow