karbor/karbor/services/protection/resource_flow.py

184 lines
7.2 KiB
Python

# 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 collections import namedtuple
from karbor.common import constants
from karbor import exception
from karbor.i18n import _LI
from karbor.services.protection import graph
from oslo_log import log as logging
LOG = logging.getLogger(__name__)
HOOKS = (
HOOK_PRE_BEGIN,
HOOK_PRE_FINISH,
HOOK_MAIN,
HOOK_COMPLETE
) = (
'on_prepare_begin',
'on_prepare_finish',
'on_main',
'on_complete'
)
ResourceHooks = namedtuple('ResourceHooks', [
HOOK_PRE_BEGIN,
HOOK_PRE_FINISH,
HOOK_MAIN,
HOOK_COMPLETE,
])
OPERATION_EXTRA_ARGS = {
constants.OPERATION_RESTORE: ['heat_template'],
}
def noop_handle(*args, **kwargs):
pass
class ResourceFlowGraphWalkerListener(graph.GraphWalkerListener):
def __init__(self, resource_flow, operation_type, context, parameters,
plugins, workflow_engine):
super(ResourceFlowGraphWalkerListener, self).__init__()
self.operation_type = operation_type
self.context = context
self.parameters = parameters or {}
self.plugins = plugins
self.workflow_engine = workflow_engine
self.flow = resource_flow
self.node_tasks = {}
self.task_stack = []
self.current_resource = None
def _create_hook_tasks(self, operation_obj, resource):
pre_begin_task = self._create_hook_task(operation_obj, resource,
HOOK_PRE_BEGIN)
pre_finish_task = self._create_hook_task(operation_obj, resource,
HOOK_PRE_FINISH)
main_task = self._create_hook_task(operation_obj, resource,
HOOK_MAIN)
post_task = self._create_hook_task(operation_obj, resource,
HOOK_COMPLETE)
return ResourceHooks(pre_begin_task, pre_finish_task, main_task,
post_task)
def _create_hook_task(self, operation_obj, resource, hook_type):
method = getattr(operation_obj, hook_type, noop_handle)
assert callable(method), 'Resource {} method "{}" is not callable' \
.format(resource.type, hook_type)
task_name = "{operation_type}_{hook_type}_{type}_{id}".format(
type=resource.type,
id=resource.id,
hook_type=hook_type,
operation_type=self.operation_type,
)
parameters = {}
parameters.update(self.parameters.get(resource.type, {}))
resource_id = '{}#{}'.format(resource.type, resource.id)
parameters.update(self.parameters.get(resource_id, {}))
injects = {
'context': self.context,
'parameters': parameters,
'resource': resource,
}
requires = list(injects)
requires.append('checkpoint')
requires.extend(OPERATION_EXTRA_ARGS.get(self.operation_type, []))
task = self.workflow_engine.create_task(method,
name=task_name,
inject=injects,
requires=requires)
return task
def on_node_enter(self, node, already_visited):
resource = node.value
LOG.debug(
"Enter node (type: %(type)s id: %(id)s visited: %(visited)s)",
{"type": resource.type, "id": resource.id, "visited":
already_visited}
)
self.current_resource = resource
if already_visited:
self.task_stack.append(self.node_tasks[resource.id])
return
if resource.type not in self.plugins:
raise exception.ProtectionPluginNotFound(type=resource.type)
protection_plugin = self.plugins[resource.type]
operation_getter_name = 'get_{}_operation'.format(self.operation_type)
operation_getter = getattr(protection_plugin, operation_getter_name)
assert callable(operation_getter)
operation_obj = operation_getter(resource)
hooks = self._create_hook_tasks(operation_obj, resource)
LOG.debug("added operation %s hooks", self.operation_type)
self.node_tasks[resource.id] = hooks
self.task_stack.append(hooks)
self.workflow_engine.add_tasks(self.flow, hooks.on_prepare_begin,
hooks.on_prepare_finish, hooks.on_main,
hooks.on_complete)
self.workflow_engine.link_task(self.flow, hooks.on_prepare_begin,
hooks.on_prepare_finish)
self.workflow_engine.link_task(self.flow, hooks.on_prepare_finish,
hooks.on_main)
self.workflow_engine.link_task(self.flow, hooks.on_main,
hooks.on_complete)
def on_node_exit(self, node):
resource = node.value
LOG.debug(
"Exit node (type: %(type)s id: %(id)s)",
{"type": resource.type, "id": resource.id}
)
child_hooks = self.task_stack.pop()
if len(self.task_stack) > 0:
parent_hooks = self.task_stack[-1]
self.workflow_engine.link_task(self.flow,
parent_hooks.on_prepare_begin,
child_hooks.on_prepare_begin)
self.workflow_engine.link_task(self.flow,
child_hooks.on_prepare_finish,
parent_hooks.on_prepare_finish)
self.workflow_engine.link_task(self.flow, child_hooks.on_complete,
parent_hooks.on_complete)
def build_resource_flow(operation_type, context, workflow_engine,
plugins, resource_graph, parameters):
LOG.info(_LI("Build resource flow for operation %s"), operation_type)
resource_graph_flow = workflow_engine.build_flow(
'ResourceGraphFlow_{}'.format(operation_type),
'graph',
)
resource_walker = ResourceFlowGraphWalkerListener(resource_graph_flow,
operation_type,
context,
parameters,
plugins,
workflow_engine)
walker = graph.GraphWalker()
walker.register_listener(resource_walker)
LOG.debug("Starting resource graph walk (operation %s)", operation_type)
walker.walk_graph(resource_graph)
LOG.debug("Finished resource graph walk (operation %s)", operation_type)
return resource_graph_flow