Merge "virt: introduce libosinfo library to set hardware policy"

nova/exception.py

@@ -2067,3 +2067,8 @@ class RealtimeMaskNotFoundOrInvalid(Invalid):
     msg_fmt = _("Realtime policy needs vCPU(s) mask configured with at least "
                 "1 RT vCPU and 1 ordinary vCPU. See hw:cpu_realtime_mask "
                 "or hw_cpu_realtime_mask")
+
+
+class OsInfoNotFound(NotFound):
+    msg_fmt = _("No configuration information found for operating system "
+                "%(os_name)s")

nova/tests/unit/virt/test_osinfo.py

@@ -0,0 +1,53 @@
+# Copyright 2015 Red Hat, Inc
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import mock
+
+from nova import exception
+from nova import test
+from nova.virt import osinfo
+
+
+class LibvirtOsInfoTest(test.NoDBTestCase):
+
+    def setUp(self):
+        super(LibvirtOsInfoTest, self).setUp()
+        osinfo.libosinfo = mock.Mock()
+
+    def test_get_os(self):
+        filter_mock = mock.Mock()
+        osinfo.libosinfo = mock.Mock()
+        osinfo.libosinfo.Filter.new.return_value = filter_mock
+        osinfo_mock = mock.Mock()
+        filtered_list = osinfo_mock.new_filtered
+        filtered_list.return_value.get_length.return_value = 1
+        os_info_db = osinfo._OsInfoDatabase.get_instance()
+        os_info_db.oslist = osinfo_mock
+        os_info_db.get_os('test33')
+        filter_mock.add_constraint.assert_called_once_with('short-id',
+                                                           'test33')
+        self.assertTrue(filtered_list.return_value.get_nth.called)
+
+    def test_get_os_fails(self):
+        filter_mock = mock.Mock()
+        osinfo.libosinfo = mock.Mock()
+        osinfo.libosinfo.Filter.return_value.new.return_value = filter_mock
+        osinfo_mock = mock.Mock()
+        filtered = osinfo_mock.new_filtered.return_value
+        filtered.get_length.return_value = 0
+        os_info_db = osinfo._OsInfoDatabase.get_instance()
+        os_info_db.oslist = osinfo_mock
+        self.assertRaises(exception.OsInfoNotFound,
+                          os_info_db.get_os,
+                          'test33')

nova/virt/osinfo.py

@@ -0,0 +1,113 @@
+# Copyright 2015 Red Hat, Inc
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from oslo_log import log as logging
+from oslo_utils import importutils
+
+from nova import exception
+from nova.i18n import _, _LE
+
+libosinfo = None
+LOG = logging.getLogger(__name__)
+
+# TODO(vladikr) The current implementation will serve only as a temporary
+# solution, due to it's dependency on the libosinfo gobject library.
+# In the future it will be replaced by a pure python library or by a direct
+# parsing of the libosinfo XML files. However, it will be possible only when
+# libosinfo project will declare the XML structure to be a stable ABI.
+
+
+class _OsInfoDatabase(object):
+
+    _instance = None
+
+    def __init__(self):
+
+        global libosinfo
+        if libosinfo is None:
+            try:
+                libosinfo = importutils.import_module(
+                                             'gi.repository.Libosinfo')
+            except ImportError as exp:
+                raise exception.NovaException(
+                                _("Cannot load Libosinfo: (%s)") % exp)
+
+        self.loader = libosinfo.Loader()
+        self.loader.process_default_path()
+
+        self.db = self.loader.get_db()
+        self.oslist = self.db.get_os_list()
+
+    @classmethod
+    def get_instance(cls):
+        """Get libosinfo connection
+        """
+        if cls._instance is None:
+            cls._instance = _OsInfoDatabase()
+
+        return cls._instance
+
+    def get_os(self, os_name):
+        """Retrieve OS object based on id, unique URI identifier of the OS
+           :param os_name: id - the unique operating systemidentifier
+                           e.g. http://fedoraproject.org/fedora/21,
+                           http://microsoft.com/win/xp,
+                           or a
+                           short-id - the short name of the OS
+                           e.g. fedora21, winxp
+           :returns: The operation system object Libosinfo.Os
+           :raise exception.OsInfoNotFound: If os hasn't been found
+        """
+        if not os_name:
+            raise exception.OsInfoNotFound(os_name='Empty')
+        fltr = libosinfo.Filter.new()
+        flt_field = 'id' if os_name.startswith('http') else 'short-id'
+        fltr.add_constraint(flt_field, os_name)
+        filttered = self.oslist.new_filtered(fltr)
+        list_len = filttered.get_length()
+        if not list_len:
+            raise exception.OsInfoNotFound(os_name=os_name)
+        return filttered.get_nth(0)
+
+
+class OsInfo(object):
+    """OS Information Structure
+    """
+
+    def __init__(self, os_name):
+        self._os_obj = self._get_os_obj(os_name)
+
+    def _get_os_obj(self, os_name):
+        try:
+            return _OsInfoDatabase.get_instance().get_os(os_name)
+        except exception.NovaException as e:
+            LOG.error(_LE("Cannot find OS information - Reason: (%s)"), e)
+
+    @property
+    def network_model(self):
+        if self._os_obj is not None:
+            fltr = libosinfo.Filter()
+            fltr.add_constraint("class", "net")
+            devs = self._os_obj.get_all_devices(fltr)
+            if devs.get_length():
+                return devs.get_nth(0).get_name()
+
+    @property
+    def disk_model(self):
+        if self._os_obj is not None:
+            fltr = libosinfo.Filter()
+            fltr.add_constraint("class", "block")
+            devs = self._os_obj.get_all_devices(fltr)
+            if devs.get_length():
+                return devs.get_nth(0).get_name()