virt-manager/virtinst/connection.py

451 lines
14 KiB
Python

#
# Copyright 2013, 2014, 2015 Red Hat, Inc.
#
# This work is licensed under the GNU GPLv2 or later.
# See the COPYING file in the top-level directory.
import os
import weakref
import libvirt
from . import Capabilities
from . import pollhelpers
from . import support
from . import xmlutil
from .guest import Guest
from .logger import log
from .nodedev import NodeDevice
from .storage import StoragePool, StorageVolume
from .uri import URI, MagicURI
def _real_local_libvirt_version():
"""
Lookup the local libvirt library version, but cache the value since
it never changes.
"""
key = "__virtinst_cached_getVersion"
if not hasattr(libvirt, key):
setattr(libvirt, key, libvirt.getVersion())
return getattr(libvirt, key)
class VirtinstConnection(object):
"""
Wrapper for libvirt connection that provides various bits like
- caching static data
- lookup for API feature support
- simplified API wrappers that handle new and old ways of doing things
"""
@staticmethod
def get_app_cache_dir():
ret = os.environ.get("XDG_CACHE_HOME")
if not ret:
ret = os.path.expanduser("~/.cache")
return os.path.join(ret, "virt-manager")
@staticmethod
def in_testsuite():
return xmlutil.in_testsuite()
def __init__(self, uri):
_initial_uri = uri or ""
if MagicURI.uri_is_magic(_initial_uri):
self._magic_uri = MagicURI(_initial_uri)
self._open_uri = self._magic_uri.open_uri
self._uri = self._magic_uri.fakeuri or self._open_uri
self._fake_conn_predictable = self._magic_uri.predictable
self._fake_conn_version = self._magic_uri.conn_version
self._fake_libvirt_version = self._magic_uri.libvirt_version
else:
self._magic_uri = None
self._open_uri = _initial_uri
self._uri = _initial_uri
self._fake_conn_predictable = False
self._fake_libvirt_version = None
self._fake_conn_version = None
self._daemon_version = None
self._conn_version = None
self._libvirtconn = None
self._uriobj = URI(self._uri)
self._caps = None
self._fetch_cache = {}
# These let virt-manager register a callback which provides its
# own cached object lists, rather than doing fresh calls
self.cb_fetch_all_domains = None
self.cb_fetch_all_pools = None
self.cb_fetch_all_vols = None
self.cb_fetch_all_nodedevs = None
self.cb_cache_new_pool = None
self.support = support.SupportCache(weakref.proxy(self))
##############
# Properties #
##############
def __getattr__(self, attr):
# Proxy virConnect API calls
libvirtconn = self.__dict__.get("_libvirtconn")
return getattr(libvirtconn, attr)
def _get_uri(self):
return self._uri or self._open_uri
uri = property(_get_uri)
def _get_caps(self):
if not self._caps:
capsxml = self._libvirtconn.getCapabilities()
self._caps = Capabilities(self, capsxml)
log.debug("Fetched capabilities for %s: %s", self._uri, capsxml)
return self._caps
caps = property(_get_caps)
def get_conn_for_api_arg(self):
return self._libvirtconn
###################
# Private helpers #
###################
def _log_versions(self):
def format_version(num):
major = int(num / 1000000)
minor = int(num / 1000) % 1000
micro = num % 1000
return "%s.%s.%s" % (major, minor, micro)
log.debug("libvirt URI versions library=%s driver=%s hypervisor=%s",
format_version(self.local_libvirt_version()),
format_version(self.daemon_version()),
format_version(self.conn_version()))
##############
# Public API #
##############
def close(self):
ret = 0
if self._libvirtconn:
ret = self._libvirtconn.close()
self._libvirtconn = None
self._uri = None
self._fetch_cache = {}
return ret
def fake_conn_predictable(self):
return self._fake_conn_predictable
def invalidate_caps(self):
self._caps = None
def is_open(self):
return bool(self._libvirtconn)
def open(self, authcb, cbdata):
if self._magic_uri:
self._magic_uri.validate()
# Mirror the set of libvirt.c virConnectCredTypeDefault
valid_auth_options = [
libvirt.VIR_CRED_AUTHNAME,
libvirt.VIR_CRED_ECHOPROMPT,
libvirt.VIR_CRED_REALM,
libvirt.VIR_CRED_PASSPHRASE,
libvirt.VIR_CRED_NOECHOPROMPT,
libvirt.VIR_CRED_EXTERNAL,
]
open_flags = 0
conn = libvirt.openAuth(self._open_uri,
[valid_auth_options, authcb, cbdata],
open_flags)
if self._magic_uri:
self._magic_uri.overwrite_conn_functions(conn)
self._libvirtconn = conn
if not self._open_uri:
self._uri = self._libvirtconn.getURI()
self._uriobj = URI(self._uri)
self._log_versions()
self._get_caps() # cache and log capabilities
def get_libvirt_data_root_dir(self):
if self.is_privileged():
return "/var/lib/libvirt"
return os.environ.get("XDG_DATA_HOME",
os.path.expanduser("~/.local/share/libvirt"))
####################
# Polling routines #
####################
_FETCH_KEY_DOMAINS = "vms"
_FETCH_KEY_POOLS = "pools"
_FETCH_KEY_VOLS = "vols"
_FETCH_KEY_NODEDEVS = "nodedevs"
def _fetch_helper(self, key, raw_cb, override_cb):
if override_cb:
return override_cb() # pragma: no cover
if key not in self._fetch_cache:
self._fetch_cache[key] = raw_cb()
return self._fetch_cache[key][:]
def _fetch_all_domains_raw(self):
dummy1, dummy2, ret = pollhelpers.fetch_vms(
self, {}, lambda obj, ignore: obj)
domains = []
for obj in ret:
# TOCTOU race: a domain may go away in between enumeration and inspection
try:
xml = obj.XMLDesc(0)
except libvirt.libvirtError as e: # pragma: no cover
log.debug("Fetching domain XML failed: %s", e)
continue
domains.append(Guest(weakref.proxy(self), parsexml=xml))
return domains
def _build_pool_raw(self, poolobj):
return StoragePool(weakref.proxy(self),
parsexml=poolobj.XMLDesc(0))
def _fetch_all_pools_raw(self):
dummy1, dummy2, ret = pollhelpers.fetch_pools(
self, {}, lambda obj, ignore: obj)
pools = []
for poolobj in ret:
# TOCTOU race: a pool may go away in between enumeration and inspection
try:
pool = self._build_pool_raw(poolobj)
except libvirt.libvirtError as e: # pragma: no cover
log.debug("Fetching pool XML failed: %s", e)
continue
pools.append(pool)
return pools
def _fetch_all_nodedevs_raw(self):
dummy1, dummy2, ret = pollhelpers.fetch_nodedevs(
self, {}, lambda obj, ignore: obj)
return [NodeDevice(weakref.proxy(self), obj.XMLDesc(0))
for obj in ret]
def _fetch_vols_raw(self, poolxmlobj):
ret = []
# TOCTOU race: a volume may go away in between enumeration and inspection
try:
pool = self._libvirtconn.storagePoolLookupByName(poolxmlobj.name)
except libvirt.libvirtError: # pragma: no cover
return ret
if pool.info()[0] != libvirt.VIR_STORAGE_POOL_RUNNING:
return ret
dummy1, dummy2, vols = pollhelpers.fetch_volumes(
self, pool, {}, lambda obj, ignore: obj)
for vol in vols:
try:
xml = vol.XMLDesc(0)
ret.append(StorageVolume(weakref.proxy(self), parsexml=xml))
except libvirt.libvirtError as e: # pragma: no cover
log.debug("Fetching volume XML failed: %s", e)
return ret
def _fetch_all_vols_raw(self):
ret = []
for poolxmlobj in self.fetch_all_pools():
ret.extend(self._fetch_vols_raw(poolxmlobj))
return ret
def _cache_new_pool_raw(self, poolobj):
# Make sure cache is primed
if self._FETCH_KEY_POOLS not in self._fetch_cache:
# Nothing cached yet, so next poll will pull in latest bits,
# so there's nothing to do
return
poollist = self._fetch_cache[self._FETCH_KEY_POOLS]
poolxmlobj = self._build_pool_raw(poolobj)
poollist.append(poolxmlobj)
if self._FETCH_KEY_VOLS not in self._fetch_cache:
return
vollist = self._fetch_cache[self._FETCH_KEY_VOLS]
vollist.extend(self._fetch_vols_raw(poolxmlobj))
def cache_new_pool(self, poolobj):
"""
Insert the passed poolobj into our cache
"""
if self.cb_cache_new_pool:
# pylint: disable=not-callable
return self.cb_cache_new_pool(poolobj)
return self._cache_new_pool_raw(poolobj)
def fetch_all_domains(self):
"""
Returns a list of Guest() objects
"""
return self._fetch_helper(
self._FETCH_KEY_DOMAINS,
self._fetch_all_domains_raw,
self.cb_fetch_all_domains)
def fetch_all_pools(self):
"""
Returns a list of StoragePool objects
"""
return self._fetch_helper(
self._FETCH_KEY_POOLS,
self._fetch_all_pools_raw,
self.cb_fetch_all_pools)
def fetch_all_vols(self):
"""
Returns a list of StorageVolume objects
"""
return self._fetch_helper(
self._FETCH_KEY_VOLS,
self._fetch_all_vols_raw,
self.cb_fetch_all_vols)
def fetch_all_nodedevs(self):
"""
Returns a list of NodeDevice() objects
"""
return self._fetch_helper(
self._FETCH_KEY_NODEDEVS,
self._fetch_all_nodedevs_raw,
self.cb_fetch_all_nodedevs)
#########################
# Libvirt API overrides #
#########################
def getURI(self):
return self._uri
#########################
# Public version checks #
#########################
def local_libvirt_version(self):
if self._fake_libvirt_version is not None:
return self._fake_libvirt_version
# This handles caching for us
return _real_local_libvirt_version()
def daemon_version(self):
if self._fake_libvirt_version is not None:
return self._fake_libvirt_version
if not self.is_remote():
return _real_local_libvirt_version()
if self._daemon_version is None:
self._daemon_version = 0
try:
self._daemon_version = self._libvirtconn.getLibVersion()
except Exception: # pragma: no cover
log.debug("Error calling getLibVersion", exc_info=True)
return self._daemon_version
def conn_version(self):
if self._fake_conn_version is not None:
return self._fake_conn_version
if self._conn_version is None:
self._conn_version = 0
try:
self._conn_version = self._libvirtconn.getVersion()
except Exception: # pragma: no cover
log.debug("Error calling getVersion", exc_info=True)
return self._conn_version
###################
# Public URI bits #
###################
def is_remote(self):
return bool(self._uriobj.hostname)
def is_privileged(self):
if self.get_uri_path() == "/session":
return False
if self.get_uri_path() == "/embed":
return os.getuid() == 0
return True
def is_unprivileged(self):
return not self.is_privileged()
def get_uri_hostname(self):
return self._uriobj.hostname
def get_uri_port(self):
return self._uriobj.port
def get_uri_username(self):
return self._uriobj.username
def get_uri_transport(self):
if self.get_uri_hostname() and not self._uriobj.transport:
# Libvirt defaults to transport=tls if hostname specified but
# no transport is specified
return "tls"
return self._uriobj.transport
def get_uri_path(self):
return self._uriobj.path
def get_uri_driver(self):
return self._uriobj.scheme
def is_qemu(self):
return self._uriobj.scheme.startswith("qemu")
def is_qemu_privileged(self):
return (self.is_qemu() and self.is_privileged())
def is_qemu_unprivileged(self):
return (self.is_qemu() and self.is_unprivileged())
def is_really_test(self):
return URI(self._open_uri).scheme.startswith("test")
def is_test(self):
return self._uriobj.scheme.startswith("test")
def is_xen(self):
return (self._uriobj.scheme.startswith("xen") or
self._uriobj.scheme.startswith("libxl"))
def is_lxc(self):
return self._uriobj.scheme.startswith("lxc")
def is_openvz(self):
return self._uriobj.scheme.startswith("openvz")
def is_container_only(self):
return self.is_lxc() or self.is_openvz()
def is_vz(self):
return (self._uriobj.scheme.startswith("vz") or
self._uriobj.scheme.startswith("parallels"))
def is_bhyve(self):
return self._uriobj.scheme.startswith("bhyve")
#########################
# Support check helpers #
#########################
def support_remote_url_install(self):
ret = self.support.conn_stream()
if self._magic_uri or self.is_test():
ret = False
return self.in_testsuite() or ret