# -*- encoding: utf-8 -*-
# Copyright (c) 2015 b<>com
#
# 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 collections
from lxml import etree
import six
from watcher._i18n import _
from watcher.common import exception
from watcher.common import utils
from watcher.decision_engine.model import element
from watcher.decision_engine.model import mapping
[docs]class ModelRoot(object):
def __init__(self, stale=False):
self._nodes = utils.Struct()
self._instances = utils.Struct()
self.mapping = mapping.Mapping(self)
self.resource = utils.Struct()
self.stale = stale
def __nonzero__(self):
return not self.stale
__bool__ = __nonzero__
[docs] def assert_node(self, obj):
if not isinstance(obj, element.ComputeNode):
raise exception.IllegalArgumentException(
message=_("'obj' argument type is not valid"))
[docs] def assert_instance(self, obj):
if not isinstance(obj, element.Instance):
raise exception.IllegalArgumentException(
message=_("'obj' argument type is not valid"))
[docs] def add_node(self, node):
self.assert_node(node)
self._nodes[node.uuid] = node
[docs] def remove_node(self, node):
self.assert_node(node)
if str(node.uuid) not in self._nodes:
raise exception.ComputeNodeNotFound(name=node.uuid)
else:
del self._nodes[node.uuid]
[docs] def add_instance(self, instance):
self.assert_instance(instance)
self._instances[instance.uuid] = instance
[docs] def remove_instance(self, instance):
self.assert_instance(instance)
del self._instances[instance.uuid]
[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.add_instance(instance)
self.mapping.map(node, instance)
[docs] def unmap_instance(self, instance, node):
"""Unmap an instance from 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.add_instance(instance)
self.mapping.unmap(node, instance)
[docs] def delete_instance(self, instance, node=None):
if node is not None:
self.mapping.unmap(node, instance)
self.remove_instance(instance)
for resource in self.resource.values():
try:
resource.unset_capacity(instance)
except KeyError:
pass
[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:
"""
if source_node == destination_node:
return False
# unmap
self.mapping.unmap(source_node, instance)
# map
self.mapping.map(destination_node, instance)
return True
[docs] def get_all_compute_nodes(self):
return self._nodes
[docs] def get_node_by_uuid(self, node_uuid):
if str(node_uuid) not in self._nodes:
raise exception.ComputeNodeNotFound(name=node_uuid)
return self._nodes[str(node_uuid)]
[docs] def get_instance_by_uuid(self, uuid):
if str(uuid) not in self._instances:
raise exception.InstanceNotFound(name=uuid)
return self._instances[str(uuid)]
[docs] def get_node_by_instance_uuid(self, instance_uuid):
"""Getting host information from the guest instance
:param instance_uuid: the uuid of the instance
:return: node
"""
if str(instance_uuid) not in self.mapping.instance_mapping:
raise exception.InstanceNotFound(name=instance_uuid)
return self.get_node_by_uuid(
self.mapping.instance_mapping[str(instance_uuid)])
[docs] def get_all_instances(self):
return self._instances
[docs] def get_mapping(self):
return self.mapping
[docs] def create_resource(self, r):
self.resource[str(r.name)] = r
[docs] def get_resource_by_uuid(self, resource_id):
return self.resource[str(resource_id)]
[docs] def get_node_instances(self, node):
return self.mapping.get_node_instances(node)
def _build_compute_node_element(self, compute_node):
attrib = collections.OrderedDict(
id=six.text_type(compute_node.id), uuid=compute_node.uuid,
human_id=compute_node.human_id, hostname=compute_node.hostname,
state=compute_node.state, status=compute_node.status)
for resource_name, resource in sorted(
self.resource.items(), key=lambda x: x[0]):
res_value = resource.get_capacity(compute_node)
if res_value is not None:
attrib[resource_name] = six.text_type(res_value)
compute_node_el = etree.Element("ComputeNode", attrib=attrib)
return compute_node_el
def _build_instance_element(self, instance):
attrib = collections.OrderedDict(
uuid=instance.uuid, human_id=instance.human_id,
hostname=instance.hostname, state=instance.state)
for resource_name, resource in sorted(
self.resource.items(), key=lambda x: x[0]):
res_value = resource.get_capacity(instance)
if res_value is not None:
attrib[resource_name] = six.text_type(res_value)
instance_el = etree.Element("Instance", attrib=attrib)
return instance_el
[docs] def to_string(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 = self._build_compute_node_element(cn)
# Build mapped instance tree
node_instance_uuids = self.get_node_instances(cn)
for instance_uuid in sorted(node_instance_uuids):
instance = self.get_instance_by_uuid(instance_uuid)
instance_el = self._build_instance_element(instance)
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:
root.append(self._build_instance_element(instance))
return etree.tostring(root, pretty_print=True).decode('utf-8')
@classmethod
[docs] def from_xml(cls, data):
model = cls()
root = etree.fromstring(data)
mem = element.Resource(element.ResourceType.memory)
num_cores = element.Resource(element.ResourceType.cpu_cores)
disk = element.Resource(element.ResourceType.disk)
disk_capacity = element.Resource(element.ResourceType.disk_capacity)
model.create_resource(mem)
model.create_resource(num_cores)
model.create_resource(disk)
model.create_resource(disk_capacity)
for cn in root.findall('.//ComputeNode'):
node = element.ComputeNode(cn.get('id'))
node.uuid = cn.get('uuid')
node.hostname = cn.get('hostname')
# set capacity
mem.set_capacity(node, int(cn.get(str(mem.name))))
disk.set_capacity(node, int(cn.get(str(disk.name))))
disk_capacity.set_capacity(
node, int(cn.get(str(disk_capacity.name))))
num_cores.set_capacity(node, int(cn.get(str(num_cores.name))))
node.state = cn.get('state')
node.status = cn.get('status')
model.add_node(node)
for inst in root.findall('.//Instance'):
instance = element.Instance()
instance.uuid = inst.get('uuid')
instance.state = inst.get('state')
mem.set_capacity(instance, int(inst.get(str(mem.name))))
disk.set_capacity(instance, int(inst.get(str(disk.name))))
disk_capacity.set_capacity(
instance, int(inst.get(str(disk_capacity.name))))
num_cores.set_capacity(
instance, int(inst.get(str(num_cores.name))))
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