virt-manager/virtManager/libvirtobject.py

224 lines
6.7 KiB
Python

#
# Copyright (C) 2010, 2013 Red Hat, Inc.
# Copyright (C) 2010 Cole Robinson <crobinso@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301 USA.
#
# pylint: disable=E0611
from gi.repository import GObject
# pylint: enable=E0611
import logging
from virtManager import uihelpers
from virtManager.baseclass import vmmGObject
class vmmLibvirtObject(vmmGObject):
__gsignals__ = {
"config-changed": (GObject.SignalFlags.RUN_FIRST, None, []),
"started": (GObject.SignalFlags.RUN_FIRST, None, []),
"stopped": (GObject.SignalFlags.RUN_FIRST, None, []),
}
def __init__(self, conn, backend, key, parseclass):
vmmGObject.__init__(self)
self._conn = conn
self._backend = backend
self._key = key
self._parseclass = parseclass
self._xml = None
self._is_xml_valid = False
self._xmlobj = None
self._xmlobj_to_define = None
# These should be set by the child classes if necessary
self._inactive_xml_flags = 0
self._active_xml_flags = 0
self.connect("config-changed", self._reparse_xml)
def _cleanup(self):
pass
def _get_conn(self):
return self._conn
conn = property(_get_conn)
def get_backend(self):
return self._backend
def get_key(self):
return self._key
def change_name_backend(self, newbackend):
# Used for changing the backing object after a rename
self._backend = newbackend
def _define_name_helper(self, objtype, rename_cb, newname):
oldname = self.get_xmlobj().name
self._invalidate_xml()
xmlobj = self._get_xmlobj_to_define()
if xmlobj.name == newname:
return
logging.debug("Changing %s name from %s to %s",
objtype, oldname, newname)
origxml = xmlobj.get_xml_config()
xmlobj.name = newname
newxml = xmlobj.get_xml_config()
try:
rename_cb(self, origxml, newxml)
finally:
self._invalidate_xml()
self.emit("config-changed")
#############################################################
# Functions that should probably be overridden in sub class #
#############################################################
def get_name(self):
raise NotImplementedError()
def _XMLDesc(self, flags):
raise NotImplementedError()
def _define(self, xml):
ignore = xml
return
def delete(self, force=True):
ignore = force
##################
# Public XML API #
##################
def get_xml(self, *args, **kwargs):
"""
See _get_raw_xml for parameter docs
"""
return self.get_xmlobj(*args, **kwargs).get_xml_config()
def get_xmlobj(self, inactive=False, refresh_if_nec=True):
xml = self._get_raw_xml(inactive, refresh_if_nec)
if inactive:
# If inactive XML requested, always return a fresh object even
# the current object is inactive XML (like when the domain is
# stopped). Callers that request inactive are basically expecting
# a new copy.
return self._build_xmlobj(xml)
if not self._xmlobj:
self._reparse_xml()
return self._xmlobj
def refresh_xml(self, forcesignal=False):
# Force an xml update. Signal 'config-changed' if domain xml has
# changed since last refresh
origxml = self._xml
self._invalidate_xml()
self._xml = self._XMLDesc(self._active_xml_flags)
self._is_xml_valid = True
if origxml != self._xml or forcesignal:
self.idle_emit("config-changed")
######################################
# Internal XML cache/update routines #
######################################
def _invalidate_xml(self):
# Mark cached xml as invalid
self._is_xml_valid = False
self._xmlobj_to_define = None
##########################
# Internal API functions #
##########################
def _get_raw_xml(self, inactive=False, refresh_if_nec=True):
"""
Get object xml. If cached xml is invalid, update.
@param inactive: Return persistent XML, not the running config.
No effect if domain is not running. Use this flag
if the XML will be used for redefining a guest
@param refresh_if_nec: Check if XML is out of date, and if so,
refresh it (default behavior). Skipping a refresh is
useful to prevent updating xml in the tick loop when
it's not that important (disk/net stats)
"""
if inactive:
return self._XMLDesc(self._inactive_xml_flags)
if self._xml is None:
self.refresh_xml()
elif refresh_if_nec and not self._is_xml_valid:
self.refresh_xml()
return self._xml
def _xml_to_redefine(self):
return self.get_xml(inactive=True)
def redefine_cached(self):
if not self._xmlobj_to_define:
logging.debug("No cached XML to define, skipping.")
return
obj = self._get_xmlobj_to_define()
xml = obj.get_xml_config()
self._redefine_xml(xml)
def _reparse_xml(self, ignore=None):
self._xmlobj = self._build_xmlobj(self._get_raw_xml())
def _build_xmlobj(self, xml):
return self._parseclass(self.conn.get_backend(), parsexml=xml)
def _get_xmlobj_to_define(self):
if not self._xmlobj_to_define:
self._xmlobj_to_define = self.get_xmlobj(inactive=True)
return self._xmlobj_to_define
def _redefine_helper(self, origxml, newxml):
uihelpers.log_redefine_xml_diff(self, origxml, newxml)
if origxml != newxml:
self._define(newxml)
# Make sure we have latest XML
self.refresh_xml(forcesignal=True)
return
def _redefine_xml(self, newxml):
origxml = self._xml_to_redefine()
return self._redefine_helper(origxml, newxml)
def _redefine(self, cb):
guest = self._get_xmlobj_to_define()
return cb(guest)