virt-manager/virtinst/pollhelpers.py

268 lines
8.4 KiB
Python

#
# Copyright (C) 2013 Red Hat, Inc.
#
# This work is licensed under the GNU GPLv2 or later.
# See the COPYING file in the top-level directory.
#
from .logger import log
# Debugging helper to force old style polling
# Can be enabled with virt-manager --test-old-poll
FORCE_OLD_POLL = False
def _new_poll_helper(origmap, typename, listfunc, buildfunc):
"""
Helper for new style listAll* APIs
"""
current = {}
new = {}
objs = []
try:
objs = listfunc()
except Exception as e:
log.debug("Unable to list all %ss: %s", typename, e)
for obj in objs:
connkey = obj.name()
if connkey not in origmap:
# Object is brand new this period
current[connkey] = buildfunc(obj, connkey)
new[connkey] = current[connkey]
else:
# Previously known object
current[connkey] = origmap[connkey]
del(origmap[connkey])
return (list(origmap.values()), list(new.values()), list(current.values()))
def _old_poll_helper(origmap, typename,
active_list, inactive_list,
lookup_func, build_func):
"""
Helper routine for old style split API libvirt polling.
@origmap: Pre-existing mapping of objects, with connkey->obj mapping.
objects must have an is_active and set_active API
@typename: string describing type of objects we are polling for use
in debug messages.
@active_list: Function that returns the list of active objects
@inactive_list: Function that returns the list of inactive objects
@lookup_func: Function to get an object handle for the passed name
@build_func: Function that builds a new object class. It is passed
args of (raw libvirt object, connkey)
"""
current = {}
new = {}
newActiveNames = []
newInactiveNames = []
try:
newActiveNames = active_list()
except Exception as e:
log.debug("Unable to list active %ss: %s", typename, e)
try:
newInactiveNames = inactive_list()
except Exception as e:
log.debug("Unable to list inactive %ss: %s", typename, e)
def check_obj(name):
obj = None
connkey = name
if connkey not in origmap:
try:
obj = lookup_func(name)
except Exception as e:
log.debug("Could not fetch %s '%s': %s",
typename, connkey, e)
return
# Object is brand new this period
current[connkey] = build_func(obj, connkey)
new[connkey] = current[connkey]
else:
# Previously known object
current[connkey] = origmap[connkey]
del(origmap[connkey])
for name in newActiveNames + newInactiveNames:
try:
check_obj(name)
except Exception:
log.exception("Couldn't fetch %s '%s'", typename, name)
return (list(origmap.values()), list(new.values()), list(current.values()))
def fetch_nets(backend, origmap, build_func):
name = "network"
if backend.support.conn_listallnetworks() and not FORCE_OLD_POLL:
return _new_poll_helper(origmap, name,
backend.listAllNetworks, build_func)
else:
active_list = backend.listNetworks
inactive_list = backend.listDefinedNetworks
lookup_func = backend.networkLookupByName
return _old_poll_helper(origmap, name,
active_list, inactive_list,
lookup_func, build_func)
def fetch_pools(backend, origmap, build_func):
name = "pool"
if backend.support.conn_listallstoragepools() and not FORCE_OLD_POLL:
return _new_poll_helper(origmap, name,
backend.listAllStoragePools, build_func)
else:
active_list = backend.listStoragePools
inactive_list = backend.listDefinedStoragePools
lookup_func = backend.storagePoolLookupByName
return _old_poll_helper(origmap, name,
active_list, inactive_list,
lookup_func, build_func)
def fetch_volumes(backend, pool, origmap, build_func):
name = "volume"
if backend.support.pool_listallvolumes(pool) and not FORCE_OLD_POLL:
return _new_poll_helper(origmap, name,
pool.listAllVolumes, build_func)
else:
active_list = pool.listVolumes
def inactive_list():
return []
lookup_func = pool.storageVolLookupByName
return _old_poll_helper(origmap, name,
active_list, inactive_list,
lookup_func, build_func)
def fetch_interfaces(backend, origmap, build_func):
name = "interface"
if backend.support.conn_listallinterfaces() and not FORCE_OLD_POLL:
return _new_poll_helper(origmap, name,
backend.listAllInterfaces, build_func)
else:
active_list = backend.listInterfaces
inactive_list = backend.listDefinedInterfaces
lookup_func = backend.interfaceLookupByName
return _old_poll_helper(origmap, name,
active_list, inactive_list,
lookup_func, build_func)
def fetch_nodedevs(backend, origmap, build_func):
name = "nodedev"
if backend.support.conn_listalldevices() and not FORCE_OLD_POLL:
return _new_poll_helper(origmap, name,
backend.listAllDevices, build_func)
else:
def active_list():
return backend.listDevices(None, 0)
def inactive_list():
return []
lookup_func = backend.nodeDeviceLookupByName
return _old_poll_helper(origmap, name,
active_list, inactive_list,
lookup_func, build_func)
def _old_fetch_vms(backend, origmap, build_func):
# We can't easily use _old_poll_helper here because the domain API
# doesn't always return names like other objects, it returns
# IDs for active VMs
newActiveIDs = []
newInactiveNames = []
oldActiveIDs = {}
oldInactiveNames = {}
current = {}
new = {}
# Build list of previous vms with proper id/name mappings
for vm in list(origmap.values()):
if vm.is_active():
oldActiveIDs[vm.get_id()] = vm
else:
oldInactiveNames[vm.get_name()] = vm
try:
newActiveIDs = backend.listDomainsID()
except Exception as e:
log.debug("Unable to list active domains: %s", e)
try:
newInactiveNames = backend.listDefinedDomains()
except Exception as e:
log.exception("Unable to list inactive domains: %s", e)
def add_vm(vm):
connkey = vm.get_name()
current[connkey] = vm
del(origmap[connkey])
def check_new(rawvm, connkey):
if connkey in origmap:
vm = origmap[connkey]
del(origmap[connkey])
else:
vm = build_func(rawvm, connkey)
new[connkey] = vm
current[connkey] = vm
for _id in newActiveIDs:
if _id in oldActiveIDs:
# No change, copy across existing VM object
vm = oldActiveIDs[_id]
add_vm(vm)
else:
# Check if domain is brand new, or old one that changed state
try:
vm = backend.lookupByID(_id)
connkey = vm.name()
check_new(vm, connkey)
except Exception:
log.exception("Couldn't fetch domain id '%s'", _id)
for name in newInactiveNames:
if name in oldInactiveNames:
# No change, copy across existing VM object
vm = oldInactiveNames[name]
add_vm(vm)
else:
# Check if domain is brand new, or old one that changed state
try:
vm = backend.lookupByName(name)
connkey = name
check_new(vm, connkey)
except Exception:
log.exception("Couldn't fetch domain '%s'", name)
return (list(origmap.values()), list(new.values()), list(current.values()))
def fetch_vms(backend, origmap, build_func):
name = "domain"
if backend.support.conn_listalldomains():
return _new_poll_helper(origmap, name,
backend.listAllDomains, build_func)
else:
return _old_fetch_vms(backend, origmap, build_func)