# -*- encoding: utf-8 -*-
# Copyright (c) 2016 Intel Innovation and Research Ireland Ltd.
#
# 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.
"""
Openstack implementation of the cluster graph.
"""
from lxml import etree
import networkx as nx
from oslo_concurrency import lockutils
from oslo_log import log
import six
from watcher._i18n import _
from watcher.common import exception
from watcher.decision_engine.model import base
from watcher.decision_engine.model import element
LOG = log.getLogger(__name__)
[docs]class ModelRoot(nx.DiGraph, base.Model):
"""Cluster graph for an Openstack cluster."""
def __init__(self, stale=False):
super(ModelRoot, self).__init__()
self.stale = stale
def __nonzero__(self):
return not self.stale
__bool__ = __nonzero__
@staticmethod
[docs] def assert_node(obj):
if not isinstance(obj, element.ComputeNode):
raise exception.IllegalArgumentException(
message=_("'obj' argument type is not valid: %s") % type(obj))
@staticmethod
[docs] def assert_instance(obj):
if not isinstance(obj, element.Instance):
raise exception.IllegalArgumentException(
message=_("'obj' argument type is not valid"))
@lockutils.synchronized("model_root")
[docs] def add_node(self, node):
self.assert_node(node)
super(ModelRoot, self).add_node(node.uuid, node)
@lockutils.synchronized("model_root")
[docs] def remove_node(self, node):
self.assert_node(node)
try:
super(ModelRoot, self).remove_node(node.uuid)
except nx.NetworkXError as exc:
LOG.exception(exc)
raise exception.ComputeNodeNotFound(name=node.uuid)
@lockutils.synchronized("model_root")
[docs] def add_instance(self, instance):
self.assert_instance(instance)
try:
super(ModelRoot, self).add_node(instance.uuid, instance)
except nx.NetworkXError as exc:
LOG.exception(exc)
raise exception.InstanceNotFound(name=instance.uuid)
@lockutils.synchronized("model_root")
[docs] def remove_instance(self, instance):
self.assert_instance(instance)
super(ModelRoot, self).remove_node(instance.uuid)
@lockutils.synchronized("model_root")
[docs] def map_instance(self, instance, node):
"""Map a newly created instance to a node
:param instance: :py:class:`~.Instance` object or instance UUID
:type instance: str or :py:class:`~.Instance`
:param node: :py:class:`~.ComputeNode` object or node UUID
:type node: str or :py:class:`~.Instance`
"""
if isinstance(instance, six.string_types):
instance = self.get_instance_by_uuid(instance)
if isinstance(node, six.string_types):
node = self.get_node_by_uuid(node)
self.assert_node(node)
self.assert_instance(instance)
self.add_edge(instance.uuid, node.uuid)
@lockutils.synchronized("model_root")
[docs] def unmap_instance(self, instance, node):
if isinstance(instance, six.string_types):
instance = self.get_instance_by_uuid(instance)
if isinstance(node, six.string_types):
node = self.get_node_by_uuid(node)
self.remove_edge(instance.uuid, node.uuid)
[docs] def delete_instance(self, instance, node=None):
self.assert_instance(instance)
self.remove_instance(instance)
@lockutils.synchronized("model_root")
[docs] def migrate_instance(self, instance, source_node, destination_node):
"""Migrate single instance from source_node to destination_node
:param instance:
:param source_node:
:param destination_node:
:return:
"""
self.assert_instance(instance)
self.assert_node(source_node)
self.assert_node(destination_node)
if source_node == destination_node:
return False
# unmap
self.remove_edge(instance.uuid, source_node.uuid)
# map
self.add_edge(instance.uuid, destination_node.uuid)
return True
@lockutils.synchronized("model_root")
[docs] def get_all_compute_nodes(self):
return {uuid: cn for uuid, cn in self.nodes(data=True)
if isinstance(cn, element.ComputeNode)}
@lockutils.synchronized("model_root")
[docs] def get_node_by_uuid(self, uuid):
try:
return self._get_by_uuid(uuid)
except exception.ComputeResourceNotFound:
raise exception.ComputeNodeNotFound(name=uuid)
@lockutils.synchronized("model_root")
[docs] def get_instance_by_uuid(self, uuid):
try:
return self._get_by_uuid(uuid)
except exception.ComputeResourceNotFound:
raise exception.InstanceNotFound(name=uuid)
def _get_by_uuid(self, uuid):
try:
return self.node[uuid]
except Exception as exc:
LOG.exception(exc)
raise exception.ComputeResourceNotFound(name=uuid)
@lockutils.synchronized("model_root")
[docs] def get_node_by_instance_uuid(self, instance_uuid):
instance = self._get_by_uuid(instance_uuid)
for node_uuid in self.neighbors(instance.uuid):
node = self._get_by_uuid(node_uuid)
if isinstance(node, element.ComputeNode):
return node
raise exception.ComputeNodeNotFound(name=instance_uuid)
@lockutils.synchronized("model_root")
[docs] def get_all_instances(self):
return {uuid: inst for uuid, inst in self.nodes(data=True)
if isinstance(inst, element.Instance)}
@lockutils.synchronized("model_root")
[docs] def get_node_instances(self, node):
self.assert_node(node)
node_instances = []
for instance_uuid in self.predecessors(node.uuid):
instance = self._get_by_uuid(instance_uuid)
if isinstance(instance, element.Instance):
node_instances.append(instance)
return node_instances
[docs] def to_string(self):
return self.to_xml()
[docs] def to_xml(self):
root = etree.Element("ModelRoot")
# Build compute node tree
for cn in sorted(self.get_all_compute_nodes().values(),
key=lambda cn: cn.uuid):
compute_node_el = cn.as_xml_element()
# Build mapped instance tree
node_instances = self.get_node_instances(cn)
for instance in sorted(node_instances, key=lambda x: x.uuid):
instance_el = instance.as_xml_element()
compute_node_el.append(instance_el)
root.append(compute_node_el)
# Build unmapped instance tree (i.e. not assigned to any compute node)
for instance in sorted(self.get_all_instances().values(),
key=lambda inst: inst.uuid):
try:
self.get_node_by_instance_uuid(instance.uuid)
except (exception.InstanceNotFound, exception.ComputeNodeNotFound):
root.append(instance.as_xml_element())
return etree.tostring(root, pretty_print=True).decode('utf-8')
@classmethod
[docs] def from_xml(cls, data):
model = cls()
root = etree.fromstring(data)
for cn in root.findall('.//ComputeNode'):
node = element.ComputeNode(**cn.attrib)
model.add_node(node)
for inst in root.findall('.//Instance'):
instance = element.Instance(**inst.attrib)
model.add_instance(instance)
parent = inst.getparent()
if parent.tag == 'ComputeNode':
node = model.get_node_by_uuid(parent.get('uuid'))
model.map_instance(instance, node)
else:
model.add_instance(instance)
return model