From 653f501434889b23a5062b3fe00488d140eb79fd Mon Sep 17 00:00:00 2001 From: Adam Dorsey Date: Mon, 14 Apr 2025 14:30:14 -0400 Subject: python: backport 'feat: allow setting read buffer limit' MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Expose the limit parameter of the underlying StreamReader and StreamWriter instances. This is helpful for the use case of transferring files in and out of a VM via the QEMU guest agent's guest-file-open, guest-file-read, guest-file-write, and guest-file-close methods, as it allows pushing the buffer size up to the guest agent's limit of 48MB per transfer. Signed-off-by: Adam Dorsey cherry picked from commit python-qemu-qmp@9ba6a698344eb3b570fa4864e906c54042824cd6 cherry picked from commit python-qemu-qmp@e4d0d3f835d82283ee0e48438d1b154e18303491 [Squashed in linter fixups. --js] Signed-off-by: John Snow Reviewed-by: Daniel P. Berrangé --- python/qemu/qmp/qmp_client.py | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) (limited to 'python/qemu/qmp/qmp_client.py') diff --git a/python/qemu/qmp/qmp_client.py b/python/qemu/qmp/qmp_client.py index a87fb565ab..d826331b6d 100644 --- a/python/qemu/qmp/qmp_client.py +++ b/python/qemu/qmp/qmp_client.py @@ -170,6 +170,12 @@ class QMPClient(AsyncProtocol[Message], Events): :param name: Optional nickname for the connection, used for logging. + :param readbuflen: + The maximum buffer length for reads and writes to and from the QMP + server, in bytes. Default is 10MB. If `QMPClient` is used to + connect to a guest agent to transfer files via ``guest-file-read``/ + ``guest-file-write``, increasing this value may be required. + Basic script-style usage looks like this:: qmp = QMPClient('my_virtual_machine_name') @@ -203,14 +209,18 @@ class QMPClient(AsyncProtocol[Message], Events): #: Logger object used for debugging messages. logger = logging.getLogger(__name__) - # Read buffer limit; 10MB like libvirt default - _limit = 10 * 1024 * 1024 + # Read buffer default limit; 10MB like libvirt default + _readbuflen = 10 * 1024 * 1024 # Type alias for pending execute() result items _PendingT = Union[Message, ExecInterruptedError] - def __init__(self, name: Optional[str] = None) -> None: - super().__init__(name) + def __init__( + self, + name: Optional[str] = None, + readbuflen: int = _readbuflen + ) -> None: + super().__init__(name, readbuflen) Events.__init__(self) #: Whether or not to await a greeting after establishing a connection. -- cgit 1.4.1