From da96c55a017fbc750b49550c6e7a523dcdab0dbe Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Fri, 22 Dec 2017 11:08:41 +0100 Subject: [PATCH 23/42] qemu.py: make VM() a context manager RH-Author: Stefan Hajnoczi Message-id: <20171222110900.24813-2-stefanha@redhat.com> Patchwork-id: 78483 O-Subject: [RHV7.5 qemu-kvm-rhev PATCH 01/20] qemu.py: make VM() a context manager Bugzilla: 1519721 RH-Acked-by: Paolo Bonzini RH-Acked-by: Jeffrey Cody RH-Acked-by: Miroslav Rezanina There are a number of ways to ensure that the QEMU process is shut down when the test ends, including atexit.register(), try: finally:, or unittest.teardown() methods. All of these require extra code and the programmer must remember to add vm.shutdown(). A nice solution is context managers: with VM(binary) as vm: ... # vm is guaranteed to be shut down here Cc: Eduardo Habkost Signed-off-by: Stefan Hajnoczi Reviewed-by: Eduardo Habkost Message-id: 20170824072202.26818-2-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi (cherry picked from commit d792bc3811f22a22a46c7d9a725fd29029f54095) Signed-off-by: Stefan Hajnoczi Signed-off-by: Miroslav Rezanina --- scripts/qemu.py | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/scripts/qemu.py b/scripts/qemu.py index 880e3e8..4d8ee10 100644 --- a/scripts/qemu.py +++ b/scripts/qemu.py @@ -21,7 +21,14 @@ import qmp.qmp class QEMUMachine(object): - '''A QEMU VM''' + '''A QEMU VM + + Use this object as a context manager to ensure the QEMU process terminates:: + + with VM(binary) as vm: + ... + # vm is guaranteed to be shut down here + ''' def __init__(self, binary, args=[], wrapper=[], name=None, test_dir="/var/tmp", monitor_address=None, socket_scm_helper=None, debug=False): @@ -40,6 +47,13 @@ class QEMUMachine(object): self._socket_scm_helper = socket_scm_helper self._debug = debug + def __enter__(self): + return self + + def __exit__(self, exc_type, exc_val, exc_tb): + self.shutdown() + return False + # This can be used to add an unused monitor instance. def add_monitor_telnet(self, ip, port): args = 'tcp:%s:%d,server,nowait,telnet' % (ip, port) -- 1.8.3.1