deb-murano/murano/dsl/contracts/instances.py
Stan Lagun 584571c3d8 On-demand garbage collection
Garbage collection is triggered by io.murano.system.GC.collect()
static method. Garbage collector destroys all object that are not
reachable anymore. GC can handle objects with cross-references and
isolated object graphs. When portion of object model becomes not
reachable it destroyed in predictable order such that child objects get
destroyed before their parents and, when possible, before objects
that are subscribed to their destruction notifications.

Internally, both pre-deployment garbage collection (that was done by
comparision of ``Objects`` and ``ObjectsCopy``) and post-deployment
orphan object collection are now done through the new GC.

MuranoPL GC utilizes Python GC to track and collect objects.
The main idea is to make ObjectStore have weak links only and
prevent hard links in other dsl places so that only links between objects
remain. Then prevent Python GC to automatically delete objects that
are not used anymore and use gc.collect() to obtain a list of
objects that are both not reachable and cannot be destroyed and then
destroy them in the correct order.

Targets-blueprint: dependency-driven-resource-deallocation
Closes-Bug: #1619635
Closes-Bug: #1597747
Change-Id: I653d8f71f003afa0a1ea588c9d14198571f5ad14
2016-09-14 03:43:09 +00:00

241 lines
9.2 KiB
Python

# Copyright (c) 2016 Mirantis, 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 six
from yaql.language import specs
from yaql.language import utils
from yaql.language import yaqltypes
from murano.dsl import constants
from murano.dsl import contracts
from murano.dsl import dsl
from murano.dsl import dsl_types
from murano.dsl import exceptions
from murano.dsl import helpers
from murano.dsl import serializer
class Class(contracts.ContractMethod):
name = 'class'
@specs.parameter('name', dsl.MuranoTypeParameter(
nullable=False, lazy=True))
@specs.parameter('default_name', dsl.MuranoTypeParameter(
nullable=True, lazy=True))
@specs.parameter('version_spec', yaqltypes.String(True))
def __init__(self, name, default_name=None, version_spec=None):
self.type = name(self.context).type
self.default_type = default_name(self.context) or self.type
self.version_spec = version_spec
def validate(self):
if self.value is None or helpers.is_instance_of(
self.value, self.type.name,
self.version_spec or helpers.get_names_scope(
self.root_context)):
return self.value
if not isinstance(self.value, (dsl_types.MuranoObject,
dsl_types.MuranoObjectInterface)):
raise exceptions.ContractViolationException(
'Value is not an object')
raise exceptions.ContractViolationException(
'Object of type {0} is not compatible with '
'requested type {1}'.format(self.value.type, self.type))
def transform(self):
value = self.value
object_store = helpers.get_object_store()
if isinstance(self.value, contracts.ObjRef):
value = self.value.object_id
if value is None:
return None
if isinstance(value, dsl_types.MuranoObject):
obj = value
elif isinstance(value, dsl_types.MuranoObjectInterface):
obj = value.object
elif isinstance(value, utils.MappingType):
obj = object_store.load(
value, self.owner, context=self.root_context,
default_type=self.default_type,
scope_type=self.calling_type)
elif isinstance(value, six.string_types):
obj = object_store.get(value)
if obj is None:
if not object_store.initializing:
raise exceptions.NoObjectFoundError(value)
else:
return contracts.ObjRef(value)
else:
raise exceptions.ContractViolationException(
'Value {0} cannot be represented as class {1}'.format(
helpers.format_scalar(value), self.type))
self.value = obj
return self.validate()
def generate_schema(self):
return self.generate_class_schema(self.value, self.type)
@staticmethod
def generate_class_schema(value, type_):
types = 'muranoObject'
if '_notNull' not in value:
types = [types] + ['null']
return {
'type': types,
'muranoType': type_.name
}
class Template(contracts.ContractMethod):
name = 'template'
@specs.parameter('type_', dsl.MuranoTypeParameter(
nullable=False, lazy=True))
@specs.parameter('default_type', dsl.MuranoTypeParameter(
nullable=True, lazy=True))
@specs.parameter('version_spec', yaqltypes.String(True))
@specs.parameter(
'exclude_properties', yaqltypes.Sequence(nullable=True))
def __init__(self, engine, type_, default_type=None, version_spec=None,
exclude_properties=None):
self.type = type_(self.context).type
self.default_type = default_type(self.context) or self.type
self.version_spec = version_spec
self.exclude_properties = exclude_properties
self.engine = engine
def validate(self):
if self.value is None or helpers.is_instance_of(
self.value, self.type.name,
self.version_spec or helpers.get_names_scope(
self.root_context)):
return self.value
if not isinstance(self.value, (dsl_types.MuranoObject,
dsl_types.MuranoObjectInterface)):
raise exceptions.ContractViolationException(
'Value is not an object')
raise exceptions.ContractViolationException(
'Object of type {0} is not compatible with '
'requested type {1}'.format(self.value.type, self.type))
def check_type(self):
if isinstance(self.value, utils.MappingType):
return self.value
return self.validate()
def transform(self):
object_store = helpers.get_object_store()
if self.value is None:
return None
if isinstance(self.value, dsl_types.MuranoObject):
obj = self.value
elif isinstance(self.value, dsl_types.MuranoObjectInterface):
obj = self.value.object
elif isinstance(self.value, utils.MappingType):
passkey = utils.create_marker('<Contract Passkey>')
if self.exclude_properties:
parsed = helpers.parse_object_definition(
self.value, self.calling_type, self.context)
props = dsl.to_mutable(parsed['properties'], self.engine)
for p in self.exclude_properties:
helpers.patch_dict(props, p, passkey)
parsed['properties'] = props
value = helpers.assemble_object_definition(parsed)
else:
value = self.value
with helpers.thread_local_attribute(
constants.TL_CONTRACT_PASSKEY, passkey):
with helpers.thread_local_attribute(
constants.TL_OBJECTS_DRY_RUN, True):
obj = object_store.load(
value, self.owner, context=self.context,
default_type=self.default_type,
scope_type=self.calling_type)
obj.__passkey__ = passkey
else:
raise exceptions.ContractViolationException(
'Value {0} cannot be represented as class {1}'.format(
helpers.format_scalar(self.value), self.type))
self.value = obj
return self.validate()
def finalize(self):
if self.value is None:
return None
object_store = helpers.get_object_store()
passkey = getattr(self.value, '__passkey__', None)
with helpers.thread_local_attribute(
constants.TL_CONTRACT_PASSKEY, passkey):
result = serializer.serialize(
self.value.real_this, object_store.executor,
dsl_types.DumpTypes.Mixed)
if self.exclude_properties:
for p in self.exclude_properties:
helpers.patch_dict(result, p, utils.NO_VALUE)
return result
def generate_schema(self):
result = Class.generate_class_schema(self.value, self.type)
result['owned'] = True
if self.exclude_properties:
result['excludedProperties'] = self.exclude_properties
return result
class Owned(contracts.ContractMethod):
name = 'owned'
def validate(self):
if self.value is None or isinstance(self.value, contracts.ObjRef):
return self.value
if isinstance(self.value, dsl_types.MuranoObject):
if helpers.find_object_owner(self.value, lambda t: t is self.this):
return self.value
raise exceptions.ContractViolationException(
'Object {0} violates owned() contract'.format(self.value))
raise exceptions.ContractViolationException(
'Value {0} is not an object'.format(self.value))
def transform(self):
return self.validate()
def generate_schema(self):
self.value['owned'] = True
return self.value
class NotOwned(contracts.ContractMethod):
name = 'not_owned'
def validate(self):
if self.value is None or isinstance(self.value, contracts.ObjRef):
return self.value
if isinstance(self.value, dsl_types.MuranoObject):
if helpers.find_object_owner(self.value, lambda t: t is self.this):
raise exceptions.ContractViolationException(
'Object {0} violates notOwned() contract'.format(
self.value))
return self.value
raise exceptions.ContractViolationException(
'Value {0} is not an object'.format(self.value))
def transform(self):
return self.validate()
def generate_schema(self):
self.value['owned'] = False
return self.value