Commit Graph

25 Commits

Author SHA1 Message Date
John Snow
6bfebc7306 python/aqmp: Return cleared events from EventListener.clear()
This serves two purposes:

(1) It is now possible to discern whether or not clear() removed any
event(s) from the queue with absolute certainty, and

(2) It is now very easy to get a List of all pending events in one
chunk, which is useful for the sync bridge.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210923004938.3999963-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-10-12 12:22:10 -04:00
John Snow
16cce725ed python/aqmp: add .empty() method to EventListener
Synchronous clients may want to know if they're about to block waiting
for an event or not. A method such as this is necessary to implement a
compatible interface for the old QEMUMonitorProtocol using the new async
internals.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210923004938.3999963-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-10-12 12:22:10 -04:00
John Snow
0257209a09 python/aqmp: add greeting property to QMPClient
Expose the greeting as a read-only property of QMPClient so it can be
retrieved at-will.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210923004938.3999963-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-10-12 12:22:10 -04:00
G S Niteesh Babu
99e45a6131 python/aqmp-tui: Add syntax highlighting
Add syntax highlighting for the incoming and outgoing QMP messages.
This is achieved using the pygments module which was added in a
previous commit.

The current implementation is a really simple one which doesn't
allow for any configuration. In future this has to be improved
to allow for easier theme config using an external config of
some sort.

Signed-off-by: G S Niteesh Babu <niteesh.gs@gmail.com>
Message-Id: <20210823220746.28295-6-niteesh.gs@gmail.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
G S Niteesh Babu
aeb6b48a47 python/aqmp-tui: Add AQMP TUI
Added AQMP TUI.

Implements the follwing basic features:
1) Command transmission/reception.
2) Shows events asynchronously.
3) Shows server status in the bottom status bar.
4) Automatic retries on disconnects and error conditions.

Also added type annotations and necessary pylint/mypy configurations.

Signed-off-by: G S Niteesh Babu <niteesh.gs@gmail.com>
Message-Id: <20210823220746.28295-3-niteesh.gs@gmail.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
ed6d4d7a95 python/aqmp: add scary message
Add a warning whenever AQMP is used to steer people gently away from
using it for the time-being.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-24-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
debbabd77f python/aqmp: add asyncio_run compatibility wrapper
As a convenience. It isn't used by the library itself, but it is used by
the test suite. It will also come in handy for users of the library
still on Python 3.6.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-23-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
41f4f92260 python/aqmp: add _raw() execution interface
This is added in anticipation of wanting it for a synchronous wrapper
for the iotest interface. Normally, execute() and execute_msg() both
raise QMP errors in the form of Python exceptions.

Many iotests expect the entire reply as-is. To reduce churn there, add a
private execution interface that will ease transition churn. However, I
do not wish to encourage its use, so it will remain a private interface.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-22-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
e0fea0b3ac python/aqmp: add execute() interfaces
Add execute() and execute_msg().

_execute() is split into _issue() and _reply() halves so that
hypothetical subclasses of QMP that want to support different execution
paradigms can do so.

I anticipate a synchronous interface may have need of separating the
send/reply phases. However, I do not wish to expose that interface here
and want to actively discourage it, so they remain private interfaces.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-21-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
577737be55 python/aqmp: Add message routing to QMP protocol
Add the ability to handle and route messages in qmp_protocol.py. The
interface for actually sending anything still isn't added until next
commit.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-20-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
c67d696b85 python/aqmp: add QMP protocol support
The star of our show!

Add most of the QMP protocol, sans support for actually executing
commands. No problem, that happens in the next several commits.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-18-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
b3cda213a7 python/aqmp: add QMP event support
This class was designed as a "mix-in" primarily so that the feature
could be given its own treatment in its own python module.

It gets quite a bit too long otherwise.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-16-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
ad07299941 python/aqmp: add well-known QMP object models
The QMP spec doesn't define very many objects that are iron-clad in
their format, but there are a few. This module makes it trivial to
validate them without relying on an external third-party library.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-15-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
08f98a2231 python/aqmp: add QMP Message format
The Message class is here primarily to serve as a solid type to use for
mypy static typing for unambiguous annotation and documentation.

We can also stuff JSON serialization and deserialization into this class
itself so it can be re-used even outside this infrastructure.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-14-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
762bd4d7a7 python/aqmp: add AsyncProtocol._readline() method
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>
2021-09-27 12:10:29 -04:00
John Snow
12c7a57f5b python/aqmp: add _cb_inbound and _cb_outbound logging hooks
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>
2021-09-27 12:10:29 -04:00
John Snow
2686ac1316 python/aqmp: add configurable read buffer limit
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>
2021-09-27 12:10:29 -04:00
John Snow
774c64a58d python/aqmp: add AsyncProtocol.accept() method
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>
2021-09-27 12:10:29 -04:00
John Snow
50e533061f python/aqmp: add logging to AsyncProtocol
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>
2021-09-27 12:10:29 -04:00
John Snow
c1408345af python/aqmp: Add logging utility helpers
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
c58b42e095 python/aqmp: add runstate state machine to AsyncProtocol
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>
2021-09-27 12:10:29 -04:00
John Snow
4ccaab0377 python/aqmp: add generic async message-based protocol support
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>
2021-09-27 12:10:29 -04:00
John Snow
a07616d612 python/aqmp: add asyncio compatibility wrappers
Python 3.6 does not have all of the goodies that Python 3.7 does, and we
need to support both. Add some compatibility wrappers needed for this
purpose.

(Note: Python 3.6 is EOL December 2021.)

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20210915162955.333025-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
fbfb6a37a3 python/aqmp: add error classes
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:29 -04:00
John Snow
a093a65567 python/aqmp: add asynchronous QMP (AQMP) subpackage
For now, it's empty! Soon, it won't be.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20210915162955.333025-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-09-27 12:10:27 -04:00