deb-murano/murano/dsl/executor.py
Alexander Tivelkov c4c8be61e0 Concurrent Execution Control
Added a meta-attrbute class `io.murano.metadata.Synchronize` which may
be attached to any Murano methods to control which objects should
Murano Executor use as synchronization primitives for concurrent
exeutions of the marked methods.
No two methods cannot be called concurrently if their use the same
synhronization objects.
By default (if no attribute is present) the old behavior is preserved:
method calls are synchronized on the objects they are called for.

The attribute has two properties:

* `onThis` (defaults to true) indicates that the method calls should
  be synchronized on target object.
* `onArgs` (defaults to an empty list) indicated that the method calls
  should be synchronized on the values of arguments with the specified
  names.

Truly 'thread-safe' methods may be declared by providing this
attribute with `onThis` set to 'false' and `onArgs` set to default
empty list value.

Executor is modified to properly use this attribute.

Targets-blueprint: application-development-framework

Change-Id: Iea028df1105c57a31a22887916c2428929b83e59
2016-07-28 19:24:50 +03:00

446 lines
18 KiB
Python

# Copyright (c) 2014 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 collections
import contextlib
import itertools
import eventlet
import eventlet.event
from oslo_log import log as logging
import six
from yaql.language import exceptions as yaql_exceptions
from yaql.language import specs
from yaql.language import utils
from murano.common.i18n import _LW
from murano.dsl import attribute_store
from murano.dsl import constants
from murano.dsl import dsl
from murano.dsl import dsl_types
from murano.dsl import exceptions as dsl_exceptions
from murano.dsl import helpers
from murano.dsl import object_store
from murano.dsl.principal_objects import stack_trace
from murano.dsl import yaql_integration
LOG = logging.getLogger(__name__)
class MuranoDslExecutor(object):
def __init__(self, package_loader, context_manager, session=None):
self._package_loader = package_loader
self._context_manager = context_manager
self._session = session
self._attribute_store = attribute_store.AttributeStore()
self._object_store = object_store.ObjectStore(self)
self._locks = {}
self._root_context_cache = {}
@property
def object_store(self):
return self._object_store
@property
def execution_session(self):
return self._session
@property
def attribute_store(self):
return self._attribute_store
@property
def package_loader(self):
return self._package_loader
@property
def context_manager(self):
return self._context_manager
def invoke_method(self, method, this, context, args, kwargs,
skip_stub=False):
if isinstance(this, dsl.MuranoObjectInterface):
this = this.object
kwargs = utils.filter_parameters_dict(kwargs)
runtime_version = method.declaring_type.package.runtime_version
yaql_engine = yaql_integration.choose_yaql_engine(runtime_version)
if context is None or not skip_stub:
actions_only = context is None and not method.name.startswith('.')
method_context = self.create_method_context(
self.create_object_context(this, context), method)
method_context[constants.CTX_SKIP_FRAME] = True
method_context[constants.CTX_ACTIONS_ONLY] = actions_only
stub = method.static_stub if isinstance(
this, dsl_types.MuranoType) else method.instance_stub
if stub is None:
raise ValueError(
'Method {0} cannot be called on receiver {1}'.format(
method, this))
real_this = this.real_this if isinstance(
this, dsl_types.MuranoObject) else this.get_reference()
return stub(yaql_engine, method_context, real_this)(
*args, **kwargs)
if context[constants.CTX_ACTIONS_ONLY] and not method.is_action:
raise dsl_exceptions.MethodNotExposed(
'{0} is not an action'.format(method.name))
if method.is_static:
obj_context = self.create_object_context(
method.declaring_type, context)
else:
obj_context = self.create_object_context(this, context)
context = self.create_method_context(obj_context, method)
if isinstance(this, dsl_types.MuranoObject):
this = this.real_this
if method.arguments_scheme is not None:
args, kwargs = self._canonize_parameters(
method.arguments_scheme, args, kwargs, method.name, this)
this_lock = this
arg_values_for_lock = {}
method_meta = [m for m in method.get_meta(context)
if m.type.name == ('io.murano.metadata.'
'engine.Synchronize')]
if method_meta:
method_meta = method_meta[0]
if method_meta:
if not method_meta.get_property('onThis', context):
this_lock = None
for arg_name in method_meta.get_property('onArgs', context):
arg_val = kwargs.get(arg_name)
if arg_val is not None:
arg_values_for_lock[arg_name] = arg_val
arg_values_for_lock = utils.filter_parameters_dict(arg_values_for_lock)
with self._acquire_method_lock(method, this_lock, arg_values_for_lock):
for i, arg in enumerate(args, 2):
context[str(i)] = arg
for key, value in six.iteritems(kwargs):
context[key] = value
def call():
if isinstance(method.body, specs.FunctionDefinition):
if isinstance(this, dsl_types.MuranoType):
native_this = this.get_reference()
else:
native_this = dsl.MuranoObjectInterface(this.cast(
method.declaring_type))
return method.body(
yaql_engine, context, native_this)(*args, **kwargs)
else:
context[constants.CTX_NAMES_SCOPE] = \
method.declaring_type
return (None if method.body is None
else method.body.execute(context))
if (not isinstance(method.body, specs.FunctionDefinition) or
not method.body.meta.get(constants.META_NO_TRACE)):
with self._log_method(context, args, kwargs) as log:
result = call()
log(result)
return result
else:
return call()
@contextlib.contextmanager
def _acquire_method_lock(self, method, this, arg_val_dict):
if this is None:
if not arg_val_dict:
# if neither "this" nor argument values are set then no
# locking is needed
key = None
else:
# if only the argument values are passed then find the lock
# list only by the method
key = (None, id(method))
else:
if method.is_static:
# find the lock list by the type and method
key = (id(method.declaring_type), id(method))
else:
# find the lock list by the object and method
key = (this.object_id, id(method))
thread_id = helpers.get_current_thread_id()
while True:
event, event_owner = None, None
if key is None: # no locking needed
break
lock_list = self._locks.setdefault(key, [])
# lock list contains a list of tuples:
# first item of each tuple is a dict with the values of locking
# arguments (it is used for argument values comparison),
# second item is an event to wait on,
# third one is the owner thread id
# If this lock list is empty it means no locks on this object and
# method at all.
for arg_vals, l_event, l_event_owner in lock_list:
if arg_vals == arg_val_dict:
event = l_event
event_owner = l_event_owner
break
if event:
if event_owner == thread_id:
# this means a re-entrant lock: the tuple with the same
# value of the first element exists in the list, but it was
# acquired by the same green thread. We may proceed with
# the call in this case
event = None
break
else:
event.wait()
else:
# this means either the lock list was empty or didn't contain a
# tuple with the first element equal to arg_val_dict.
# Then let's acquire a lock, i.e. create a new tuple and place
# it into the list
event = eventlet.event.Event()
event_owner = thread_id
lock_list.append((arg_val_dict, event, event_owner))
break
try:
yield
finally:
if event is not None:
lock_list.remove((arg_val_dict, event, event_owner))
if len(lock_list) == 0:
del self._locks[key]
event.send()
@contextlib.contextmanager
def _log_method(self, context, args, kwargs):
method = helpers.get_current_method(context)
param_gen = itertools.chain(
(six.text_type(arg) for arg in args),
(u'{0} => {1}'.format(name, value)
for name, value in six.iteritems(kwargs)))
params_str = u', '.join(param_gen)
method_name = '::'.join((method.declaring_type.name, method.name))
thread_id = helpers.get_current_thread_id()
caller_str = ''
caller_ctx = helpers.get_caller_context(context)
if caller_ctx is not None:
frame = stack_trace.compose_stack_frame(caller_ctx)
if frame['location']:
caller_str = ' called from ' + stack_trace.format_frame(frame)
LOG.trace(u'{thread}: Begin execution {method}({params}){caller}'
.format(thread=thread_id, method=method_name,
params=params_str, caller=caller_str))
try:
def log_result(result):
LOG.trace(
u'{thread}: End execution {method} with result '
u'{result}'.format(
thread=thread_id, method=method_name, result=result))
yield log_result
except Exception as e:
LOG.trace(
u'{thread}: End execution {method} with exception '
u'{exc}'.format(thread=thread_id, method=method_name, exc=e))
raise
@staticmethod
def _canonize_parameters(arguments_scheme, args, kwargs,
method_name, receiver):
arg_names = list(arguments_scheme.keys())
parameter_values = {}
varargs_arg = None
vararg_values = []
kwargs_arg = None
kwarg_values = {}
for name, definition in six.iteritems(arguments_scheme):
if definition.usage == dsl_types.MethodArgumentUsages.VarArgs:
varargs_arg = name
parameter_values[name] = vararg_values
elif definition.usage == dsl_types.MethodArgumentUsages.KwArgs:
kwargs_arg = name
parameter_values[name] = kwarg_values
for i, arg in enumerate(args):
name = None if i >= len(arg_names) else arg_names[i]
if name is None or name in (varargs_arg, kwargs_arg):
if varargs_arg:
vararg_values.append(arg)
else:
raise yaql_exceptions.NoMatchingMethodException(
method_name, receiver)
else:
parameter_values[name] = arg
for name, value in six.iteritems(utils.filter_parameters_dict(kwargs)):
if name in arguments_scheme and name not in (
varargs_arg, kwargs_arg):
parameter_values[name] = value
elif kwargs_arg:
kwarg_values[name] = value
else:
raise yaql_exceptions.NoMatchingMethodException(
method_name, receiver)
return tuple(), parameter_values
def load(self, data):
with helpers.with_object_store(self.object_store):
return self._load(data)
def _load(self, data):
if not isinstance(data, dict):
raise TypeError()
self._attribute_store.load(data.get(constants.DM_ATTRIBUTES) or [])
model = data.get(constants.DM_OBJECTS)
if model is None:
return None
result = self._object_store.load(model, None, keep_ids=True)
return dsl.MuranoObjectInterface(result)
def cleanup(self, data):
objects_copy = data.get(constants.DM_OBJECTS_COPY)
if not objects_copy:
return
gc_object_store = object_store.ObjectStore(self)
with helpers.with_object_store(gc_object_store):
gc_object_store.load(objects_copy, None, keep_ids=True)
objects_to_clean = []
for object_id in self._list_potential_object_ids(objects_copy):
if (gc_object_store.has(object_id) and
not self._object_store.has(object_id)):
obj = gc_object_store.get(object_id)
objects_to_clean.append(obj)
if objects_to_clean:
for obj in objects_to_clean:
self._destroy_object(obj)
def cleanup_orphans(self, alive_object_ids):
orphan_ids = self._collect_orphans(alive_object_ids)
self._destroy_orphans(orphan_ids)
return len(orphan_ids)
def _collect_orphans(self, alive_object_ids):
orphan_ids = []
for obj_id in self._object_store.iterate():
if obj_id not in alive_object_ids:
orphan_ids.append(obj_id)
return orphan_ids
def _destroy_orphans(self, orphan_ids):
with helpers.with_object_store(self.object_store):
for obj_id in orphan_ids:
self._destroy_object(self._object_store.get(obj_id))
self._object_store.remove(obj_id)
def _destroy_object(self, obj):
methods = obj.type.find_methods(lambda m: m.name == '.destroy')
for method in methods:
try:
method.invoke(obj, (), {}, None)
except Exception as e:
LOG.warning(_LW(
'Muted exception during execution of .destroy '
'on {0}: {1}').format(obj, e), exc_info=True)
def _list_potential_object_ids(self, data):
if isinstance(data, dict):
for val in six.itervalues(data):
for res in self._list_potential_object_ids(val):
yield res
sys_dict = data.get('?')
if (isinstance(sys_dict, dict) and
sys_dict.get('id') and sys_dict.get('type')):
yield sys_dict['id']
elif isinstance(data, collections.Iterable) and not isinstance(
data, six.string_types):
for val in data:
for res in self._list_potential_object_ids(val):
yield res
def create_root_context(self, runtime_version):
context = self._root_context_cache.get(runtime_version)
if not context:
context = self.context_manager.create_root_context(runtime_version)
self._root_context_cache[runtime_version] = context
return context
def create_package_context(self, package):
root_context = self.create_root_context(package.runtime_version)
context = helpers.link_contexts(
root_context,
self.context_manager.create_package_context(package))
return context
def create_type_context(self, murano_type, caller_context=None):
package_context = self.create_package_context(
murano_type.package)
context = helpers.link_contexts(
package_context,
self.context_manager.create_type_context(
murano_type)).create_child_context()
context[constants.CTX_TYPE] = murano_type
if caller_context:
context[constants.CTX_NAMES_SCOPE] = caller_context[
constants.CTX_NAMES_SCOPE]
return context
def create_object_context(self, obj, caller_context=None):
if isinstance(obj, dsl_types.MuranoClass):
obj_type = obj
obj = None
else:
obj_type = obj.type
class_context = self.create_type_context(obj_type)
if obj is not None:
context = helpers.link_contexts(
class_context, self.context_manager.create_object_context(
obj)).create_child_context()
context[constants.CTX_THIS] = obj.real_this
context['this'] = obj.real_this
context[''] = obj.real_this
else:
context = class_context.create_child_context()
type_ref = obj_type.get_reference()
context[constants.CTX_THIS] = type_ref
context['this'] = type_ref
context[''] = type_ref
if caller_context is not None:
caller = caller_context
while caller is not None and caller[constants.CTX_SKIP_FRAME]:
caller = caller[constants.CTX_CALLER_CONTEXT]
context[constants.CTX_NAMES_SCOPE] = caller_context[
constants.CTX_NAMES_SCOPE]
context[constants.CTX_CALLER_CONTEXT] = caller
context[constants.CTX_ALLOW_PROPERTY_WRITES] = caller_context[
constants.CTX_ALLOW_PROPERTY_WRITES]
else:
context[constants.CTX_NAMES_SCOPE] = obj_type
return context
@staticmethod
def create_method_context(object_context, method):
context = object_context.create_child_context()
context[constants.CTX_CURRENT_METHOD] = method
return context
def run(self, cls, method_name, this, args, kwargs):
with helpers.with_object_store(self.object_store):
return cls.invoke(method_name, this, args, kwargs)