def get_controller(wf_ex, wf_spec=None):
"""Gets a workflow controller instance by given workflow execution object.
:param wf_ex: Workflow execution object.
:param wf_spec: Workflow specification object. If passed, the method works
faster.
:returns: Workflow controller class.
"""
if not wf_spec:
wf_spec = spec_parser.get_workflow_spec(wf_ex['spec'])
wf_type = wf_spec.get_type()
ctrl_cls = None
for cls in u.iter_subclasses(WorkflowController):
if cls.__workflow_type__ == wf_type:
ctrl_cls = cls
break
if not ctrl_cls:
raise exc.NotFoundException(
'Failed to find a workflow controller [type=%s]' % wf_type
)
return ctrl_cls(wf_ex, wf_spec)
def register_length_validator(attr_name):
"""Register an event listener on the attribute that will
validate the size every time a 'set' occurs.
"""
for cls in utils.iter_subclasses(Execution):
if hasattr(cls, attr_name):
event.listen(
getattr(cls, attr_name), "set", lambda t, v, o, i: validate_long_type_length(cls, attr_name, v)
)
def register_secure_model_hooks():
# Make sure 'project_id' is always properly set.
for sec_model_class in utils.iter_subclasses(MistralSecureModelBase):
if '__abstract__' not in sec_model_class.__dict__:
event.listen(
sec_model_class.project_id,
'set',
_set_project_id,
retval=True
)
def _get_class(wf_type):
"""Gets a workflow controller class by given workflow type.
:param wf_type: Workflow type.
:returns: Workflow controller class.
"""
for wf_ctrl_cls in u.iter_subclasses(WorkflowController):
if wf_type == wf_ctrl_cls.__workflow_type__:
return wf_ctrl_cls
msg = 'Failed to find a workflow controller [type=%s]' % wf_type
raise exc.NotFoundException(msg)
def get_class(wf_type):
"""Gets a task specification list class by given workflow type.
:param wf_type: Workflow type
:returns: Task specification list class
"""
for spec_list_cls in utils.iter_subclasses(TaskSpecList):
if wf_type == spec_list_cls.__type__:
return spec_list_cls
msg = ("Can not find task list specification with workflow type:"
" %s" % wf_type)
raise exc.NotFoundException(msg)
def test_itersubclasses(self):
class A(object):
pass
class B(A):
pass
class C(A):
pass
class D(C):
pass
self.assertEqual([B, C, D], list(utils.iter_subclasses(A)))
def instantiate_spec(spec_cls, data):
"""Instantiates specification accounting for specification hierarchies.
:param spec_cls: Specification concrete or base class. In case if base
class or the hierarchy is provided this method relies on attributes
_polymorphic_key and _polymorphic_value in order to find a concrete
class that needs to be instantiated.
:param data: Raw specification data as a dictionary.
"""
if issubclass(spec_cls, BaseSpecList):
# Ignore polymorphic search for specification lists because
# it doesn't make sense for them.
return spec_cls(data)
if not hasattr(spec_cls, '_polymorphic_key'):
spec = spec_cls(data)
spec.validate_semantics()
return spec
key = spec_cls._polymorphic_key
if not isinstance(key, tuple):
key_name = key
key_default = None
else:
key_name = key[0]
key_default = key[1]
for cls in utils.iter_subclasses(spec_cls):
if not hasattr(cls, '_polymorphic_value'):
raise exc.DSLParsingException(
"Class '%s' is expected to have attribute '_polymorphic_value'"
" because it's a part of specification hierarchy inherited "
"from class '%s'." % (cls, spec_cls)
)
if cls._polymorphic_value == data.get(key_name, key_default):
spec = cls(data)
spec.validate_semantics()
return cls(data)
raise exc.DSLParsingException(
'Failed to find a specification class to instantiate '
'[spec_cls=%s, data=%s]' % (spec_cls, data)
)
def test_itersubclasses(self):
class A(object):
pass
class B(A):
pass
class C(A):
pass
class D(C):
pass
self.assertEqual([B, C, D], list(utils.iter_subclasses(A)))
def instantiate_spec(spec_cls, data):
"""Instantiates specification accounting for specification hierarchies.
:param spec_cls: Specification concrete or base class. In case if base
class or the hierarchy is provided this method relies on attributes
_polymorphic_key and _polymorphic_value in order to find a concrete
class that needs to be instantiated.
:param data: Raw specification data as a dictionary.
"""
if issubclass(spec_cls, BaseSpecList):
# Ignore polymorphic search for specification lists because
# it doesn't make sense for them.
return spec_cls(data)
if not hasattr(spec_cls, '_polymorphic_key'):
spec = spec_cls(data)
spec.validate_semantics()
return spec
key = spec_cls._polymorphic_key
if not isinstance(key, tuple):
key_name = key
key_default = None
else:
key_name = key[0]
key_default = key[1]
for cls in utils.iter_subclasses(spec_cls):
if not hasattr(cls, '_polymorphic_value'):
raise exc.DSLParsingException(
"Class '%s' is expected to have attribute '_polymorphic_value'"
" because it's a part of specification hierarchy inherited "
"from class '%s'." % (cls, spec_cls))
if cls._polymorphic_value == data.get(key_name, key_default):
spec = cls(data)
spec.validate_semantics()
return spec
raise exc.DSLParsingException(
'Failed to find a specification class to instantiate '
'[spec_cls=%s, data=%s]' % (spec_cls, data))
}
# Main properties.
action_spec = sa.Column(st.JsonDictType())
# Whether the task is fully processed (publishing and calculating commands
# after it). It allows to simplify workflow controller implementations
# significantly.
processed = sa.Column(sa.BOOLEAN, default=False)
# Data Flow properties.
in_context = sa.Column(st.JsonLongDictType())
published = sa.Column(st.JsonDictType())
for cls in utils.iter_subclasses(Execution):
event.listen(
# Catch and trim Execution.state_info to always fit allocated size.
cls.state_info,
'set',
lambda t, v, o, i: utils.cut(v, 1020),
retval=True
)
# Many-to-one for 'Execution' and 'TaskExecution'.
Execution.task_execution_id = sa.Column(
sa.String(36),
sa.ForeignKey(TaskExecution.id),
nullable=True
)
def instantiate_spec(spec_cls, data, validate=False):
"""Instantiates specification accounting for specification hierarchies.
:param spec_cls: Specification concrete or base class. In case if base
class or the hierarchy is provided this method relies on attributes
_polymorphic_key and _polymorphic_value in order to find a concrete
class that needs to be instantiated.
:param data: Raw specification data as a dictionary.
:type data: dict
:param validate: If it equals False then semantics and schema validation
will be skipped
:type validate: bool
"""
if issubclass(spec_cls, BaseSpecList):
# Ignore polymorphic search for specification lists because
# it doesn't make sense for them.
return spec_cls(data, validate)
if not hasattr(spec_cls, '_polymorphic_key'):
spec = spec_cls(data, validate)
if validate:
spec.validate_semantics()
return spec
# In order to do polymorphic search we need to make sure that
# a spec is backed by a dictionary. Otherwise we can't extract
# a polymorphic key.
if not isinstance(data, dict):
raise exc.InvalidModelException(
"A specification with polymorphic key must be backed by"
" a dictionary [spec_cls=%s, data=%s]" % (spec_cls, data))
key = spec_cls._polymorphic_key
if not isinstance(key, tuple):
key_name = key
key_default = None
else:
key_name = key[0]
key_default = key[1]
for cls in utils.iter_subclasses(spec_cls):
if not hasattr(cls, '_polymorphic_value'):
raise exc.DSLParsingException(
"Class '%s' is expected to have attribute '_polymorphic_value'"
" because it's a part of specification hierarchy inherited "
"from class '%s'." % (cls, spec_cls))
if cls._polymorphic_value == data.get(key_name, key_default):
spec = cls(data, validate)
if validate:
spec.validate_semantics()
return spec
raise exc.DSLParsingException(
'Failed to find a specification class to instantiate '
'[spec_cls=%s, data=%s]' % (spec_cls, data))
processed = sa.Column(sa.BOOLEAN, default=False)
# Data Flow properties.
in_context = sa.Column(st.JsonLongDictType())
published = sa.Column(st.JsonLongDictType())
@property
def executions(self):
return (
self.action_executions
if not self.spec.get('workflow')
else self.workflow_executions
)
for cls in utils.iter_subclasses(Execution):
event.listen(
# Catch and trim Execution.state_info to always fit allocated size.
# Note that the limit is 65500 which is less than 65535 (2^16 -1).
# The reason is that utils.cut() is not exactly accurate in case if
# the value is not a string, but, for example, a dictionary. If we
# limit it exactly to 65535 then once in a while it may go slightly
# beyond the allowed maximum size. It may depend on the order of
# keys in a string representation and other things that are hidden
# inside utils.cut_dict() method.
cls.state_info,
'set',
lambda t, v, o, i: utils.cut(v, 65500),
retval=True
)
def instantiate_spec(spec_cls, data, validate=False):
"""Instantiates specification accounting for specification hierarchies.
:param spec_cls: Specification concrete or base class. In case if base
class or the hierarchy is provided this method relies on attributes
_polymorphic_key and _polymorphic_value in order to find a concrete
class that needs to be instantiated.
:param data: Raw specification data as a dictionary.
:type data: dict
:param validate: If it equals False then semantics and schema validation
will be skipped
:type validate: bool
"""
if issubclass(spec_cls, BaseSpecList):
# Ignore polymorphic search for specification lists because
# it doesn't make sense for them.
return spec_cls(data, validate)
if not hasattr(spec_cls, '_polymorphic_key'):
spec = spec_cls(data, validate)
if validate:
spec.validate_semantics()
return spec
# In order to do polymorphic search we need to make sure that
# a spec is backed by a dictionary. Otherwise we can't extract
# a polymorphic key.
if not isinstance(data, dict):
raise exc.InvalidModelException(
"A specification with polymorphic key must be backed by"
" a dictionary [spec_cls=%s, data=%s]" % (spec_cls, data)
)
key = spec_cls._polymorphic_key
if not isinstance(key, tuple):
key_name = key
key_default = None
else:
key_name = key[0]
key_default = key[1]
for cls in utils.iter_subclasses(spec_cls):
if not hasattr(cls, '_polymorphic_value'):
raise exc.DSLParsingException(
"Class '%s' is expected to have attribute '_polymorphic_value'"
" because it's a part of specification hierarchy inherited "
"from class '%s'." % (cls, spec_cls)
)
if cls._polymorphic_value == data.get(key_name, key_default):
spec = cls(data, validate)
if validate:
spec.validate_semantics()
return spec
raise exc.DSLParsingException(
'Failed to find a specification class to instantiate '
'[spec_cls=%s, data=%s]' % (spec_cls, data)
)
