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Posted to dev@ariatosca.apache.org by mx...@apache.org on 2016/12/18 14:30:55 UTC

[1/4] incubator-ariatosca git commit: reorded storage

Repository: incubator-ariatosca
Updated Branches:
  refs/heads/ARIA-39-Genericize-storage-models 89dfdb61c -> 24b55dacc


http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/orchestrator/workflows/executor/test_executor.py
----------------------------------------------------------------------
diff --git a/tests/orchestrator/workflows/executor/test_executor.py b/tests/orchestrator/workflows/executor/test_executor.py
index a425799..291a48c 100644
--- a/tests/orchestrator/workflows/executor/test_executor.py
+++ b/tests/orchestrator/workflows/executor/test_executor.py
@@ -20,7 +20,7 @@ from contextlib import contextmanager
 import pytest
 import retrying
 
-from aria.storage import models
+from aria.storage import model
 from aria.orchestrator import events
 from aria.orchestrator.workflows.executor import (
     thread,
@@ -104,7 +104,7 @@ class MockException(Exception):
 
 class MockTask(object):
 
-    INFINITE_RETRIES = models.Task.INFINITE_RETRIES
+    INFINITE_RETRIES = model.Task.INFINITE_RETRIES
 
     def __init__(self, func, inputs=None, ctx=None):
         self.states = []
@@ -120,7 +120,7 @@ class MockTask(object):
         self.retry_count = 0
         self.max_attempts = 1
 
-        for state in models.Task.STATES:
+        for state in model.Task.STATES:
             setattr(self, state.upper(), state)
 
     @contextmanager

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/storage/__init__.py
----------------------------------------------------------------------
diff --git a/tests/storage/__init__.py b/tests/storage/__init__.py
index c455bfa..9101fd0 100644
--- a/tests/storage/__init__.py
+++ b/tests/storage/__init__.py
@@ -17,7 +17,7 @@ import platform
 from tempfile import mkdtemp
 from shutil import rmtree
 
-from aria.storage import models
+from aria.storage import model
 from sqlalchemy import (
     create_engine,
     orm)
@@ -59,7 +59,7 @@ def get_sqlite_api_kwargs(base_dir=None, filename='db.sqlite'):
     session_factory = orm.sessionmaker(bind=engine)
     session = scoped_session(session_factory=session_factory) if base_dir else session_factory()
 
-    models.DeclarativeBase.metadata.create_all(bind=engine)
+    model.DeclarativeBase.metadata.create_all(bind=engine)
     return dict(engine=engine, session=session)
 
 
@@ -76,4 +76,4 @@ def release_sqlite_storage(storage):
             session.rollback()
             session.close()
         for engine in set(mapi._engine for mapi in mapis):
-            models.DeclarativeBase.metadata.drop_all(engine)
+            model.DeclarativeBase.metadata.drop_all(engine)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/storage/test_model_storage.py
----------------------------------------------------------------------
diff --git a/tests/storage/test_model_storage.py b/tests/storage/test_model_storage.py
index e5aee5a..7441099 100644
--- a/tests/storage/test_model_storage.py
+++ b/tests/storage/test_model_storage.py
@@ -15,47 +15,75 @@
 
 import pytest
 
+from sqlalchemy import Column, Text, Integer
+
 from aria.storage import (
     ModelStorage,
-    models,
+    model,
     exceptions,
     sql_mapi,
+    structure,
+    type as aria_type,
 )
 from aria import application_model_storage
 from tests.storage import get_sqlite_api_kwargs, release_sqlite_storage
 
 
+class MockModel(model.DeclarativeBase, structure.ModelBase):
+    __tablename__ = 'mock_models'
+    some_dict = Column(aria_type.Dict)
+    value = Column(Integer)
+    name = Column(Text)
+
+
 @pytest.fixture
 def storage():
     base_storage = ModelStorage(sql_mapi.SQLAlchemyModelAPI, api_kwargs=get_sqlite_api_kwargs())
+    base_storage.register(MockModel)
     yield base_storage
     release_sqlite_storage(base_storage)
 
 
+@pytest.fixture(scope='module', autouse=True)
+def module_cleanup():
+    model.DeclarativeBase.metadata.remove(MockModel.__table__)
+
+
 def test_storage_base(storage):
     with pytest.raises(AttributeError):
         storage.non_existent_attribute()
 
 
 def test_model_storage(storage):
-    storage.register(models.ProviderContext)
+    mock_model = MockModel(value=0, name='model_name')
+    storage.mock_model.put(mock_model)
 
-    pc = models.ProviderContext(context={}, name='context_name')
-    storage.provider_context.put(pc)
+    assert storage.mock_model.get_by_name('model_name') == mock_model
 
-    assert storage.provider_context.get_by_name('context_name') == pc
+    assert [mm_from_storage for mm_from_storage in storage.mock_model.iter()] == [mock_model]
+    assert [mm_from_storage for mm_from_storage in storage.mock_model] == [mock_model]
 
-    assert [pc_from_storage for pc_from_storage in storage.provider_context.iter()] == [pc]
-    assert [pc_from_storage for pc_from_storage in storage.provider_context] == [pc]
+    storage.mock_model.delete(mock_model)
+    with pytest.raises(exceptions.StorageError):
+        storage.mock_model.get(mock_model.id)
 
-    new_context = {'update_key': 0}
-    pc.context = new_context
-    storage.provider_context.update(pc)
-    assert storage.provider_context.get(pc.id).context == new_context
 
-    storage.provider_context.delete(pc)
-    with pytest.raises(exceptions.StorageError):
-        storage.provider_context.get(pc.id)
+def test_inner_dict_update(storage):
+    inner_dict = {'inner_value': 1}
+
+    mock_model = MockModel(some_dict={'inner_dict': inner_dict, 'value': 0})
+    storage.mock_model.put(mock_model)
+
+    storage_mm = storage.mock_model.get(mock_model.id)
+    assert storage_mm == mock_model
+
+    storage_mm.some_dict['inner_dict']['inner_value'] = 2
+    storage_mm.some_dict['value'] = -1
+    storage.mock_model.update(storage_mm)
+    storage_mm = storage.mock_model.get(storage_mm.id)
+
+    assert storage_mm.some_dict['inner_dict']['inner_value'] == 2
+    assert storage_mm.some_dict['value'] == -1
 
 
 def test_application_storage_factory():
@@ -70,6 +98,5 @@ def test_application_storage_factory():
     assert storage.deployment_update_step
     assert storage.deployment_modification
     assert storage.execution
-    assert storage.provider_context
 
     release_sqlite_storage(storage)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/storage/test_models.py
----------------------------------------------------------------------
diff --git a/tests/storage/test_models.py b/tests/storage/test_models.py
index 2985eca..80f9fd3 100644
--- a/tests/storage/test_models.py
+++ b/tests/storage/test_models.py
@@ -12,19 +12,21 @@
 # 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 contextlib import contextmanager
 from datetime import datetime
+from contextlib import contextmanager
+
 import pytest
 
 from aria import application_model_storage
-from aria.storage import exceptions
-from aria.storage import sql_mapi
-from aria.storage.models import (
+from aria.storage import (
+    exceptions,
+    sql_mapi,
+)
+from aria.storage.model import (
     DeploymentUpdateStep,
     Blueprint,
     Execution,
     Task,
-    ProviderContext,
     Plugin,
     Deployment,
     Node,
@@ -835,23 +837,3 @@ class TestTask(object):
             create_task(max_attempts=0)
         with pytest.raises(ValueError):
             create_task(max_attempts=-2)
-
-
-def test_inner_dict_update(empty_storage):
-    inner_dict = {'inner_value': 1}
-    pc = ProviderContext(name='name', context={
-        'inner_dict': inner_dict,
-        'value': 0
-    })
-    empty_storage.provider_context.put(pc)
-
-    storage_pc = empty_storage.provider_context.get(pc.id)
-    assert storage_pc == pc
-
-    storage_pc.context['inner_dict']['inner_value'] = 2
-    storage_pc.context['value'] = -1
-    empty_storage.provider_context.update(storage_pc)
-    storage_pc = empty_storage.provider_context.get(pc.id)
-
-    assert storage_pc.context['inner_dict']['inner_value'] == 2
-    assert storage_pc.context['value'] == -1


[4/4] incubator-ariatosca git commit: fixed some private fields

Posted by mx...@apache.org.
fixed some private fields


Project: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/commit/24b55dac
Tree: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/tree/24b55dac
Diff: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/diff/24b55dac

Branch: refs/heads/ARIA-39-Genericize-storage-models
Commit: 24b55daccceb22483ef92e89eb8365f082939ac1
Parents: c58987a
Author: mxmrlv <mx...@gmail.com>
Authored: Sun Dec 18 16:30:42 2016 +0200
Committer: mxmrlv <mx...@gmail.com>
Committed: Sun Dec 18 16:30:42 2016 +0200

----------------------------------------------------------------------
 aria/storage/base_model.py | 73 +++++++++++++++++++----------------------
 1 file changed, 33 insertions(+), 40 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/24b55dac/aria/storage/base_model.py
----------------------------------------------------------------------
diff --git a/aria/storage/base_model.py b/aria/storage/base_model.py
index 4fb23a2..1f1a80c 100644
--- a/aria/storage/base_model.py
+++ b/aria/storage/base_model.py
@@ -129,8 +129,8 @@ class ExecutionBase(ModelBase):
     """
     # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
     id = None
-
     __tablename__ = 'executions'
+    _private_fields = ['deployment_fk']
 
     TERMINATED = 'terminated'
     FAILED = 'failed'
@@ -150,24 +150,21 @@ class ExecutionBase(ModelBase):
         CANCELLING: END_STATES
     }
 
-    # TODO: maintenance_mode and executions tests fail when the validation is on.
-    # @orm.validates('status')
-    # def validate_status(self, key, value):
-    #     """Validation function that verifies execution status transitions are OK"""
-    #     try:
-    #         current_status = getattr(self, key)
-    #     except AttributeError:
-    #         return
-    #     valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
-    #     if all([current_status is not None,
-    #             current_status != value,
-    #             value not in valid_transitions]):
-    #         raise ValueError('Cannot change execution status from {current} to {new}'.format(
-    #             current=current_status,
-    #             new=value))
-    #     return value
-
-    _private_fields = ['deployment_id', 'blueprint_id']
+    @orm.validates('status')
+    def validate_status(self, key, value):
+        """Validation function that verifies execution status transitions are OK"""
+        try:
+            current_status = getattr(self, key)
+        except AttributeError:
+            return
+        valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
+        if all([current_status is not None,
+                current_status != value,
+                value not in valid_transitions]):
+            raise ValueError('Cannot change execution status from {current} to {new}'.format(
+                current=current_status,
+                new=value))
+        return value
 
     created_at = Column(DateTime, index=True)
     started_at = Column(DateTime, nullable=True, index=True)
@@ -210,7 +207,7 @@ class DeploymentUpdateBase(ModelBase):
 
     __tablename__ = 'deployment_updates'
 
-    _private_fields = ['execution_id', 'deployment_id']
+    _private_fields = ['execution_fk', 'deployment_fk']
 
     created_at = Column(DateTime, nullable=False, index=True)
     deployment_plan = Column(Dict, nullable=False)
@@ -257,8 +254,8 @@ class DeploymentUpdateStepBase(ModelBase):
     """
     # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
     id = None
-
     __tablename__ = 'deployment_update_steps'
+    _private_fields = ['deployment_update_fk']
 
     _action_types = namedtuple('ACTION_TYPES', 'ADD, REMOVE, MODIFY')
     ACTION_TYPES = _action_types(ADD='add', REMOVE='remove', MODIFY='modify')
@@ -280,7 +277,6 @@ class DeploymentUpdateStepBase(ModelBase):
         PLUGIN='plugin'
     )
 
-    _private_fields = ['deployment_update_id']
 
     action = Column(Enum(*ACTION_TYPES, name='action_type'), nullable=False)
     entity_id = Column(Text, nullable=False)
@@ -333,6 +329,7 @@ class DeploymentModificationBase(ModelBase):
     Deployment modification model representation.
     """
     __tablename__ = 'deployment_modifications'
+    _private_fields = ['deployment_fk']
 
     STARTED = 'started'
     FINISHED = 'finished'
@@ -341,8 +338,6 @@ class DeploymentModificationBase(ModelBase):
     STATES = [STARTED, FINISHED, ROLLEDBACK]
     END_STATES = [FINISHED, ROLLEDBACK]
 
-    _private_fields = ['deployment_id']
-
     context = Column(Dict)
     created_at = Column(DateTime, nullable=False, index=True)
     ended_at = Column(DateTime, index=True)
@@ -374,7 +369,7 @@ class NodeBase(ModelBase):
     # See base class for an explanation on these properties
     is_id_unique = False
 
-    _private_fields = ['blueprint_id', 'deployment_id', 'host_id']
+    _private_fields = ['blueprint_fk', 'host_fk']
 
     @declared_attr
     def host_id(cls):
@@ -465,7 +460,7 @@ class NodeInstanceBase(ModelBase):
     Node instance model representation.
     """
     __tablename__ = 'node_instances'
-    _private_fields = ['node_id', 'host_id']
+    _private_fields = ['node_fk', 'host_fk']
 
     runtime_properties = Column(Dict)
     scaling_groups = Column(List)
@@ -576,9 +571,7 @@ class TaskBase(ModelBase):
     A Model which represents an task
     """
     __tablename__ = 'tasks'
-    _private_fields = ['node_instance_id',
-                       'relationship_instance_id',
-                       'execution_id']
+    _private_fields = ['node_instance_fk', 'relationship_instance_fk', 'execution_fk']
 
     @declared_attr
     def node_instance_fk(cls):
@@ -592,17 +585,17 @@ class TaskBase(ModelBase):
     def node_instance(cls):
         return cls.one_to_many_relationship('node_instance_fk', 'NodeInstance')
 
-    # @declared_attr
-    # def relationship_instance_fk(cls):
-    #     return cls.foreign_key('relationship_instances', nullable=True)
-    #
-    # @declared_attr
-    # def relationship_instance_id(cls):
-    #     return association_proxy('relationship_instance', cls.user_id_column())
-    #
-    # @declared_attr
-    # def relationship_instance(cls):
-    #     return cls.one_to_many_relationship('relationship_instance_fk', 'RelationshipInstance')
+    @declared_attr
+    def relationship_instance_fk(cls):
+        return cls.foreign_key('relationship_instances', nullable=True)
+
+    @declared_attr
+    def relationship_instance_id(cls):
+        return association_proxy('relationship_instance', cls.user_id_column())
+
+    @declared_attr
+    def relationship_instance(cls):
+        return cls.one_to_many_relationship('relationship_instance_fk', 'RelationshipInstance')
 
     PENDING = 'pending'
     RETRYING = 'retrying'


[3/4] incubator-ariatosca git commit: wip

Posted by mx...@apache.org.
wip


Project: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/commit/c58987a9
Tree: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/tree/c58987a9
Diff: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/diff/c58987a9

Branch: refs/heads/ARIA-39-Genericize-storage-models
Commit: c58987a9a34e1f4bebbf557c1c0fb221c7993338
Parents: 3ac35f6
Author: mxmrlv <mx...@gmail.com>
Authored: Sun Dec 18 13:00:08 2016 +0200
Committer: mxmrlv <mx...@gmail.com>
Committed: Sun Dec 18 13:00:08 2016 +0200

----------------------------------------------------------------------
 aria/storage/base_model.py | 72 ++++++++++++++++++++++-------------------
 aria/storage/structure.py  | 18 ++++++-----
 2 files changed, 48 insertions(+), 42 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/c58987a9/aria/storage/base_model.py
----------------------------------------------------------------------
diff --git a/aria/storage/base_model.py b/aria/storage/base_model.py
index 77c351d..4fb23a2 100644
--- a/aria/storage/base_model.py
+++ b/aria/storage/base_model.py
@@ -150,21 +150,22 @@ class ExecutionBase(ModelBase):
         CANCELLING: END_STATES
     }
 
-    @orm.validates('status')
-    def validate_status(self, key, value):
-        """Validation function that verifies execution status transitions are OK"""
-        try:
-            current_status = getattr(self, key)
-        except AttributeError:
-            return
-        valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
-        if all([current_status is not None,
-                current_status != value,
-                value not in valid_transitions]):
-            raise ValueError('Cannot change execution status from {current} to {new}'.format(
-                current=current_status,
-                new=value))
-        return value
+    # TODO: maintenance_mode and executions tests fail when the validation is on.
+    # @orm.validates('status')
+    # def validate_status(self, key, value):
+    #     """Validation function that verifies execution status transitions are OK"""
+    #     try:
+    #         current_status = getattr(self, key)
+    #     except AttributeError:
+    #         return
+    #     valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
+    #     if all([current_status is not None,
+    #             current_status != value,
+    #             value not in valid_transitions]):
+    #         raise ValueError('Cannot change execution status from {current} to {new}'.format(
+    #             current=current_status,
+    #             new=value))
+    #     return value
 
     _private_fields = ['deployment_id', 'blueprint_id']
 
@@ -182,7 +183,7 @@ class ExecutionBase(ModelBase):
 
     @declared_attr
     def deployment_fk(cls):
-        return cls.foreign_key('deployments', nullable=False)
+        return cls.foreign_key('deployments', nullable=True)
 
     @declared_attr
     def deployment(cls):
@@ -213,9 +214,9 @@ class DeploymentUpdateBase(ModelBase):
 
     created_at = Column(DateTime, nullable=False, index=True)
     deployment_plan = Column(Dict, nullable=False)
-    deployment_update_node_instances = Column(Dict)
+    deployment_update_node_instances = Column(List)
     deployment_update_deployment = Column(Dict)
-    deployment_update_nodes = Column(Dict)
+    deployment_update_nodes = Column(List)
     modified_entity_ids = Column(Dict)
     state = Column(Text)
 
@@ -225,7 +226,7 @@ class DeploymentUpdateBase(ModelBase):
 
     @declared_attr
     def execution_id(cls):
-        return association_proxy('executions', cls.user_id_column())
+        return association_proxy('execution', cls.user_id_column())
 
     @declared_attr
     def execution(cls):
@@ -291,7 +292,7 @@ class DeploymentUpdateStepBase(ModelBase):
 
     @declared_attr
     def deployment_update_id(cls):
-        return association_proxy('deployment_updates', cls.user_id_column())
+        return association_proxy('deployment_update', cls.user_id_column())
 
     @declared_attr
     def deployment_update(cls):
@@ -373,7 +374,7 @@ class NodeBase(ModelBase):
     # See base class for an explanation on these properties
     is_id_unique = False
 
-    _private_fields = ['deployment_id', 'host_id']
+    _private_fields = ['blueprint_id', 'deployment_id', 'host_id']
 
     @declared_attr
     def host_id(cls):
@@ -399,13 +400,15 @@ class NodeBase(ModelBase):
     def deployment(cls):
         return cls.one_to_many_relationship('deployment_fk', 'Deployment')
 
+    blueprint_id = association_proxy('deployment', 'blueprint_id')
+
     deploy_number_of_instances = Column(Integer, nullable=False)
     max_number_of_instances = Column(Integer, nullable=False)
     min_number_of_instances = Column(Integer, nullable=False)
     number_of_instances = Column(Integer, nullable=False)
     planned_number_of_instances = Column(Integer, nullable=False)
     plugins = Column(List)
-    plugins_to_install = Column(Dict)
+    plugins_to_install = Column(List)
     properties = Column(Dict)
     operations = Column(Dict)
     type = Column(Text, nullable=False, index=True)
@@ -433,8 +436,9 @@ class RelationshipBase(ModelBase):
         return cls.one_to_many_relationship('source_node_fk',
                                             'Node',
                                             backreference='outbound_relationships')
+
     @declared_attr
-    def target_name(cls):
+    def target_id(cls):
         return association_proxy('target_node', cls.user_id_column())
 
     @declared_attr
@@ -588,17 +592,17 @@ class TaskBase(ModelBase):
     def node_instance(cls):
         return cls.one_to_many_relationship('node_instance_fk', 'NodeInstance')
 
-    @declared_attr
-    def relationship_instance_fk(cls):
-        return cls.foreign_key('relationship_instances', nullable=True)
-
-    @declared_attr
-    def relationship_instance_id(cls):
-        return association_proxy('relationship_instance', cls.user_id_column())
-
-    @declared_attr
-    def relationship_instance(cls):
-        return cls.one_to_many_relationship('relationship_instance_fk', 'RelationshipInstance')
+    # @declared_attr
+    # def relationship_instance_fk(cls):
+    #     return cls.foreign_key('relationship_instances', nullable=True)
+    #
+    # @declared_attr
+    # def relationship_instance_id(cls):
+    #     return association_proxy('relationship_instance', cls.user_id_column())
+    #
+    # @declared_attr
+    # def relationship_instance(cls):
+    #     return cls.one_to_many_relationship('relationship_instance_fk', 'RelationshipInstance')
 
     PENDING = 'pending'
     RETRYING = 'retrying'

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/c58987a9/aria/storage/structure.py
----------------------------------------------------------------------
diff --git a/aria/storage/structure.py b/aria/storage/structure.py
index dd757b7..2f6186d 100644
--- a/aria/storage/structure.py
+++ b/aria/storage/structure.py
@@ -92,18 +92,19 @@ class ModelBase(object):
         parent_table = cls._get_cls_by_tablename(parent_class)
         primaryjoin_str = \
             '{parent_class_name}.{parent_unique_id} == {child_class.__name__}.{foreign_key_column}'\
-                .format(
-                    parent_class_name=parent_class,
-                    parent_unique_id=parent_table.storage_id_column(),
-                    child_class=cls,
-                    foreign_key_column=foreign_key_column
-                )
+            .format(
+                parent_class_name=parent_class,
+                parent_unique_id=parent_table.storage_id_column(),
+                child_class=cls,
+                foreign_key_column=foreign_key_column
+            )
         return relationship(
             parent_class,
             primaryjoin=primaryjoin_str,
+            foreign_keys=[getattr(cls, foreign_key_column)],
             # The following line make sure that when the *parent* is
             # deleted, all its connected children are deleted as well
-            backref=backref(backreference or cls.__tablename__, cascade='all')
+            backref=backref(backreference or cls.__tablename__, cascade='all'),
         )
 
     @classmethod
@@ -119,7 +120,8 @@ class ModelBase(object):
             local_column=local_column)
         return relationship(cls.__name__,
                             primaryjoin=primaryjoin_str,
-                            remote_side=remote_side_str)
+                            remote_side=remote_side_str,
+                            post_update=True)
 
 
 class ModelIdMixin(object):


[2/4] incubator-ariatosca git commit: reorded storage

Posted by mx...@apache.org.
reorded storage


Project: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/commit/3ac35f63
Tree: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/tree/3ac35f63
Diff: http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/diff/3ac35f63

Branch: refs/heads/ARIA-39-Genericize-storage-models
Commit: 3ac35f63d1636b7a8ebfa931de6cb8880c24c055
Parents: 89dfdb6
Author: mxmrlv <mx...@gmail.com>
Authored: Thu Dec 15 12:16:34 2016 +0200
Committer: mxmrlv <mx...@gmail.com>
Committed: Thu Dec 15 12:16:34 2016 +0200

----------------------------------------------------------------------
 aria/__init__.py                                |  31 +-
 aria/orchestrator/context/workflow.py           |   4 +-
 aria/orchestrator/workflows/api/task.py         |  10 +-
 aria/orchestrator/workflows/core/engine.py      |  16 +-
 aria/orchestrator/workflows/core/task.py        |   8 +-
 aria/storage/__init__.py                        |  12 +-
 aria/storage/base_model.py                      | 671 ++++++++++++++++++
 aria/storage/model.py                           | 108 +++
 aria/storage/models.py                          | 111 ---
 aria/storage/models_base.py                     | 701 -------------------
 aria/storage/structure.py                       | 179 +++++
 aria/storage/structures.py                      | 267 -------
 aria/storage/type.py                            | 123 ++++
 tests/mock/models.py                            |  22 +-
 .../orchestrator/workflows/core/test_engine.py  |  14 +-
 .../workflows/executor/test_executor.py         |   6 +-
 tests/storage/__init__.py                       |   6 +-
 tests/storage/test_model_storage.py             |  57 +-
 tests/storage/test_models.py                    |  32 +-
 19 files changed, 1193 insertions(+), 1185 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/__init__.py
----------------------------------------------------------------------
diff --git a/aria/__init__.py b/aria/__init__.py
index b000397..04b74c7 100644
--- a/aria/__init__.py
+++ b/aria/__init__.py
@@ -61,22 +61,21 @@ def application_model_storage(api, api_kwargs=None):
     Initiate model storage for the supplied storage driver
     """
     models = [
-        storage.models.Plugin,
-        storage.models.ProviderContext,
-
-        storage.models.Blueprint,
-        storage.models.Deployment,
-        storage.models.DeploymentUpdate,
-        storage.models.DeploymentUpdateStep,
-        storage.models.DeploymentModification,
-
-        storage.models.Node,
-        storage.models.NodeInstance,
-        storage.models.Relationship,
-        storage.models.RelationshipInstance,
-
-        storage.models.Execution,
-        storage.models.Task,
+        storage.model.Plugin,
+
+        storage.model.Blueprint,
+        storage.model.Deployment,
+        storage.model.DeploymentUpdate,
+        storage.model.DeploymentUpdateStep,
+        storage.model.DeploymentModification,
+
+        storage.model.Node,
+        storage.model.NodeInstance,
+        storage.model.Relationship,
+        storage.model.RelationshipInstance,
+
+        storage.model.Execution,
+        storage.model.Task,
     ]
     # if api not in _model_storage:
     return storage.ModelStorage(api, items=models, api_kwargs=api_kwargs or {})

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/orchestrator/context/workflow.py
----------------------------------------------------------------------
diff --git a/aria/orchestrator/context/workflow.py b/aria/orchestrator/context/workflow.py
index f5ba86b..1365888 100644
--- a/aria/orchestrator/context/workflow.py
+++ b/aria/orchestrator/context/workflow.py
@@ -76,7 +76,7 @@ class WorkflowContext(BaseContext):
         """
         return self.model.node.iter(
             filters={
-                'deployment_id': self.deployment.id
+                'deployment_id': getattr(self.deployment, self.deployment.user_id_column())
             }
         )
 
@@ -87,7 +87,7 @@ class WorkflowContext(BaseContext):
         """
         return self.model.node_instance.iter(
             filters={
-                'deployment_id': getattr(self.deployment, self.deployment.user_id_column)
+                'deployment_id': getattr(self.deployment, self.deployment.user_id_column())
             }
         )
 

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/orchestrator/workflows/api/task.py
----------------------------------------------------------------------
diff --git a/aria/orchestrator/workflows/api/task.py b/aria/orchestrator/workflows/api/task.py
index 1c12407..93c2142 100644
--- a/aria/orchestrator/workflows/api/task.py
+++ b/aria/orchestrator/workflows/api/task.py
@@ -18,7 +18,7 @@ Provides the tasks to be entered into the task graph
 """
 from uuid import uuid4
 
-from aria.storage import models
+from aria.storage import model
 
 from ... import context
 from .. import exceptions
@@ -75,8 +75,8 @@ class OperationTask(BaseTask):
         :param actor: the operation host on which this operation is registered.
         :param inputs: operation inputs.
         """
-        assert isinstance(actor, (models.NodeInstance,
-                                  models.RelationshipInstance))
+        assert isinstance(actor, (model.NodeInstance,
+                                  model.RelationshipInstance))
         super(OperationTask, self).__init__()
         self.actor = actor
         self.name = '{name}.{actor.id}'.format(name=name, actor=actor)
@@ -97,7 +97,7 @@ class OperationTask(BaseTask):
         :param instance: the node of which this operation belongs to.
         :param name: the name of the operation.
         """
-        assert isinstance(instance, models.NodeInstance)
+        assert isinstance(instance, model.NodeInstance)
         operation_details = instance.node.operations[name]
         operation_inputs = operation_details.get('inputs', {})
         operation_inputs.update(inputs or {})
@@ -119,7 +119,7 @@ class OperationTask(BaseTask):
         with 'source_operations' and 'target_operations'
         :param inputs any additional inputs to the operation
         """
-        assert isinstance(instance, models.RelationshipInstance)
+        assert isinstance(instance, model.RelationshipInstance)
         if operation_end not in [cls.TARGET_OPERATION, cls.SOURCE_OPERATION]:
             raise exceptions.TaskException('The operation end should be {0} or {1}'.format(
                 cls.TARGET_OPERATION, cls.SOURCE_OPERATION

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/orchestrator/workflows/core/engine.py
----------------------------------------------------------------------
diff --git a/aria/orchestrator/workflows/core/engine.py b/aria/orchestrator/workflows/core/engine.py
index 2f0b3f1..7b57ae4 100644
--- a/aria/orchestrator/workflows/core/engine.py
+++ b/aria/orchestrator/workflows/core/engine.py
@@ -23,7 +23,7 @@ from datetime import datetime
 import networkx
 
 from aria import logger
-from aria.storage import models
+from aria.storage import model
 from aria.orchestrator import events
 
 from .. import exceptions
@@ -80,18 +80,18 @@ class Engine(logger.LoggerMixin):
         events.on_cancelling_workflow_signal.send(self._workflow_context)
 
     def _is_cancel(self):
-        return self._workflow_context.execution.status in [models.Execution.CANCELLING,
-                                                           models.Execution.CANCELLED]
+        return self._workflow_context.execution.status in [model.Execution.CANCELLING,
+                                                           model.Execution.CANCELLED]
 
     def _executable_tasks(self):
         now = datetime.utcnow()
         return (task for task in self._tasks_iter()
-                if task.status in models.Task.WAIT_STATES and
+                if task.status in model.Task.WAIT_STATES and
                 task.due_at <= now and
                 not self._task_has_dependencies(task))
 
     def _ended_tasks(self):
-        return (task for task in self._tasks_iter() if task.status in models.Task.END_STATES)
+        return (task for task in self._tasks_iter() if task.status in model.Task.END_STATES)
 
     def _task_has_dependencies(self, task):
         return len(self._execution_graph.pred.get(task.id, {})) > 0
@@ -103,19 +103,19 @@ class Engine(logger.LoggerMixin):
         for _, data in self._execution_graph.nodes_iter(data=True):
             task = data['task']
             if isinstance(task, engine_task.OperationTask):
-                if task.model_task.status not in models.Task.END_STATES:
+                if task.model_task.status not in model.Task.END_STATES:
                     self._workflow_context.model.task.refresh(task.model_task)
             yield task
 
     def _handle_executable_task(self, task):
         if isinstance(task, engine_task.StubTask):
-            task.status = models.Task.SUCCESS
+            task.status = model.Task.SUCCESS
         else:
             events.sent_task_signal.send(task)
             self._executor.execute(task)
 
     def _handle_ended_tasks(self, task):
-        if task.status == models.Task.FAILED and not task.ignore_failure:
+        if task.status == model.Task.FAILED and not task.ignore_failure:
             raise exceptions.ExecutorException('Workflow failed')
         else:
             self._execution_graph.remove_node(task.id)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/orchestrator/workflows/core/task.py
----------------------------------------------------------------------
diff --git a/aria/orchestrator/workflows/core/task.py b/aria/orchestrator/workflows/core/task.py
index d381916..ad4bf0a 100644
--- a/aria/orchestrator/workflows/core/task.py
+++ b/aria/orchestrator/workflows/core/task.py
@@ -24,7 +24,7 @@ from functools import (
 )
 
 from aria import logger
-from aria.storage import models
+from aria.storage import model
 from aria.orchestrator.context import operation as operation_context
 
 from .. import exceptions
@@ -66,7 +66,7 @@ class StubTask(BaseTask):
 
     def __init__(self, *args, **kwargs):
         super(StubTask, self).__init__(*args, **kwargs)
-        self.status = models.Task.PENDING
+        self.status = model.Task.PENDING
         self.due_at = datetime.utcnow()
 
 
@@ -108,10 +108,10 @@ class OperationTask(BaseTask):
         self._workflow_context = api_task._workflow_context
         base_task_model = api_task._workflow_context.model.task.model_cls
 
-        if isinstance(api_task.actor, models.NodeInstance):
+        if isinstance(api_task.actor, model.NodeInstance):
             context_class = operation_context.NodeOperationContext
             task_model_cls = base_task_model.as_node_instance
-        elif isinstance(api_task.actor, models.RelationshipInstance):
+        elif isinstance(api_task.actor, model.RelationshipInstance):
             context_class = operation_context.RelationshipOperationContext
             task_model_cls = base_task_model.as_relationship_instance
         else:

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/__init__.py
----------------------------------------------------------------------
diff --git a/aria/storage/__init__.py b/aria/storage/__init__.py
index fd69d47..a1c07d7 100644
--- a/aria/storage/__init__.py
+++ b/aria/storage/__init__.py
@@ -45,19 +45,19 @@ from .core import (
 from . import (
     exceptions,
     api,
-    structures,
+    structure,
     core,
     filesystem_rapi,
     sql_mapi,
-    models
+    model
 )
 
 __all__ = (
     'exceptions',
-    'structures',
-    # 'Storage',
-    # 'ModelStorage',
-    # 'ResourceStorage',
+    'structure',
+    'Storage',
+    'ModelStorage',
+    'ResourceStorage',
     'filesystem_rapi',
     'sql_mapi',
     'api'

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/base_model.py
----------------------------------------------------------------------
diff --git a/aria/storage/base_model.py b/aria/storage/base_model.py
new file mode 100644
index 0000000..77c351d
--- /dev/null
+++ b/aria/storage/base_model.py
@@ -0,0 +1,671 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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.
+
+"""
+Aria's storage.models module
+Path: aria.storage.models
+
+models module holds aria's models.
+
+classes:
+    * Field - represents a single field.
+    * IterField - represents an iterable field.
+    * Model - abstract model implementation.
+    * Snapshot - snapshots implementation model.
+    * Deployment - deployment implementation model.
+    * DeploymentUpdateStep - deployment update step implementation model.
+    * DeploymentUpdate - deployment update implementation model.
+    * DeploymentModification - deployment modification implementation model.
+    * Execution - execution implementation model.
+    * Node - node implementation model.
+    * Relationship - relationship implementation model.
+    * NodeInstance - node instance implementation model.
+    * RelationshipInstance - relationship instance implementation model.
+    * Plugin - plugin implementation model.
+"""
+from collections import namedtuple
+from datetime import datetime
+
+from sqlalchemy.ext.associationproxy import association_proxy
+from sqlalchemy.ext.declarative import declared_attr
+from sqlalchemy import (
+    Column,
+    Integer,
+    Text,
+    DateTime,
+    Boolean,
+    Enum,
+    String,
+    Float,
+    orm,
+)
+
+from .structure import ModelBase
+
+from .type import (
+    List,
+    Dict
+)
+
+__all__ = (
+    'BlueprintBase',
+    'DeploymentBase',
+    'DeploymentUpdateStepBase',
+    'DeploymentUpdateBase',
+    'DeploymentModificationBase',
+    'ExecutionBase',
+    'NodeBase',
+    'RelationshipBase',
+    'NodeInstanceBase',
+    'RelationshipInstanceBase',
+    'PluginBase',
+    'TaskBase'
+)
+
+#pylint: disable=no-self-argument
+
+
+class BlueprintBase(ModelBase):
+    """
+    Blueprint model representation.
+    """
+    __tablename__ = 'blueprints'
+
+    created_at = Column(DateTime, nullable=False, index=True)
+    main_file_name = Column(Text, nullable=False)
+    plan = Column(Dict, nullable=False)
+    updated_at = Column(DateTime)
+    description = Column(Text)
+
+
+class DeploymentBase(ModelBase):
+    """
+    Deployment model representation.
+    """
+    __tablename__ = 'deployments'
+
+    _private_fields = ['blueprint_fk']
+
+    created_at = Column(DateTime, nullable=False, index=True)
+    description = Column(Text)
+    inputs = Column(Dict)
+    groups = Column(Dict)
+    permalink = Column(Text)
+    policy_triggers = Column(Dict)
+    policy_types = Column(Dict)
+    outputs = Column(Dict)
+    scaling_groups = Column(List)
+    updated_at = Column(DateTime)
+    workflows = Column(List)
+
+    @declared_attr
+    def blueprint_fk(cls):
+        return cls.foreign_key('blueprints', nullable=False)
+
+    @declared_attr
+    def blueprint(cls):
+        return cls.one_to_many_relationship('blueprint_fk', 'Blueprint')
+
+    @declared_attr
+    def blueprint_id(cls):
+        return association_proxy('blueprint', cls.user_id_column())
+
+
+class ExecutionBase(ModelBase):
+    """
+    Execution model representation.
+    """
+    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
+    id = None
+
+    __tablename__ = 'executions'
+
+    TERMINATED = 'terminated'
+    FAILED = 'failed'
+    CANCELLED = 'cancelled'
+    PENDING = 'pending'
+    STARTED = 'started'
+    CANCELLING = 'cancelling'
+    FORCE_CANCELLING = 'force_cancelling'
+
+    STATES = [TERMINATED, FAILED, CANCELLED, PENDING, STARTED, CANCELLING, FORCE_CANCELLING]
+    END_STATES = [TERMINATED, FAILED, CANCELLED]
+    ACTIVE_STATES = [state for state in STATES if state not in END_STATES]
+
+    VALID_TRANSITIONS = {
+        PENDING: [STARTED, CANCELLED],
+        STARTED: END_STATES + [CANCELLING],
+        CANCELLING: END_STATES
+    }
+
+    @orm.validates('status')
+    def validate_status(self, key, value):
+        """Validation function that verifies execution status transitions are OK"""
+        try:
+            current_status = getattr(self, key)
+        except AttributeError:
+            return
+        valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
+        if all([current_status is not None,
+                current_status != value,
+                value not in valid_transitions]):
+            raise ValueError('Cannot change execution status from {current} to {new}'.format(
+                current=current_status,
+                new=value))
+        return value
+
+    _private_fields = ['deployment_id', 'blueprint_id']
+
+    created_at = Column(DateTime, index=True)
+    started_at = Column(DateTime, nullable=True, index=True)
+    ended_at = Column(DateTime, nullable=True, index=True)
+    error = Column(Text, nullable=True)
+    is_system_workflow = Column(Boolean, nullable=False, default=False)
+    parameters = Column(Dict)
+    status = Column(Enum(*STATES, name='execution_status'), default=PENDING)
+    workflow_name = Column(Text)
+
+    blueprint = association_proxy('deployment', 'blueprint')
+    blueprint_id = association_proxy('deployment', 'blueprint_id')
+
+    @declared_attr
+    def deployment_fk(cls):
+        return cls.foreign_key('deployments', nullable=False)
+
+    @declared_attr
+    def deployment(cls):
+        return cls.one_to_many_relationship('deployment_fk', 'Deployment')
+
+    @declared_attr
+    def deployment_id(cls):
+        return association_proxy('deployment', cls.user_id_column())
+
+    def __str__(self):
+        return '<{0} id=`{1}` (status={2})>'.format(
+            self.__class__.__name__,
+            self.id,
+            self.status
+        )
+
+
+class DeploymentUpdateBase(ModelBase):
+    """
+    Deployment update model representation.
+    """
+    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
+    steps = None
+
+    __tablename__ = 'deployment_updates'
+
+    _private_fields = ['execution_id', 'deployment_id']
+
+    created_at = Column(DateTime, nullable=False, index=True)
+    deployment_plan = Column(Dict, nullable=False)
+    deployment_update_node_instances = Column(Dict)
+    deployment_update_deployment = Column(Dict)
+    deployment_update_nodes = Column(Dict)
+    modified_entity_ids = Column(Dict)
+    state = Column(Text)
+
+    @declared_attr
+    def execution_fk(cls):
+        return cls.foreign_key('executions', nullable=True)
+
+    @declared_attr
+    def execution_id(cls):
+        return association_proxy('executions', cls.user_id_column())
+
+    @declared_attr
+    def execution(cls):
+        return cls.one_to_many_relationship('execution_fk', 'Execution')
+
+    @declared_attr
+    def deployment_fk(cls):
+        return cls.foreign_key('deployments')
+
+    @declared_attr
+    def deployment_id(cls):
+        return association_proxy('deployment', cls.user_id_column())
+
+    @declared_attr
+    def deployment(cls):
+        return cls.one_to_many_relationship('deployment_fk', 'Deployment')
+
+    def to_dict(self, suppress_error=False, **kwargs):
+        dep_update_dict = super(DeploymentUpdateBase, self).to_dict(suppress_error)     #pylint: disable=no-member
+        # Taking care of the fact the DeploymentSteps are _BaseModels
+        dep_update_dict['steps'] = [step.to_dict() for step in self.steps]
+        return dep_update_dict
+
+
+class DeploymentUpdateStepBase(ModelBase):
+    """
+    Deployment update step model representation.
+    """
+    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
+    id = None
+
+    __tablename__ = 'deployment_update_steps'
+
+    _action_types = namedtuple('ACTION_TYPES', 'ADD, REMOVE, MODIFY')
+    ACTION_TYPES = _action_types(ADD='add', REMOVE='remove', MODIFY='modify')
+    _entity_types = namedtuple(
+        'ENTITY_TYPES',
+        'NODE, RELATIONSHIP, PROPERTY, OPERATION, WORKFLOW, OUTPUT, DESCRIPTION, GROUP, '
+        'POLICY_TYPE, POLICY_TRIGGER, PLUGIN')
+    ENTITY_TYPES = _entity_types(
+        NODE='node',
+        RELATIONSHIP='relationship',
+        PROPERTY='property',
+        OPERATION='operation',
+        WORKFLOW='workflow',
+        OUTPUT='output',
+        DESCRIPTION='description',
+        GROUP='group',
+        POLICY_TYPE='policy_type',
+        POLICY_TRIGGER='policy_trigger',
+        PLUGIN='plugin'
+    )
+
+    _private_fields = ['deployment_update_id']
+
+    action = Column(Enum(*ACTION_TYPES, name='action_type'), nullable=False)
+    entity_id = Column(Text, nullable=False)
+    entity_type = Column(Enum(*ENTITY_TYPES, name='entity_type'), nullable=False)
+
+    @declared_attr
+    def deployment_update_fk(cls):
+        return cls.foreign_key('deployment_updates')
+
+    @declared_attr
+    def deployment_update_id(cls):
+        return association_proxy('deployment_updates', cls.user_id_column())
+
+    @declared_attr
+    def deployment_update(cls):
+        return cls.one_to_many_relationship('deployment_update_fk',
+                                            'DeploymentUpdate',
+                                            backreference='steps')
+
+    def __hash__(self):
+        return hash((self.id, self.entity_id))
+
+    def __lt__(self, other):
+        """
+        the order is 'remove' < 'modify' < 'add'
+        :param other:
+        :return:
+        """
+        if not isinstance(other, self.__class__):
+            return not self >= other
+
+        if self.action != other.action:
+            if self.action == 'remove':
+                return_value = True
+            elif self.action == 'add':
+                return_value = False
+            else:
+                return_value = other.action == 'add'
+            return return_value
+
+        if self.action == 'add':
+            return self.entity_type == 'node' and other.entity_type == 'relationship'
+        if self.action == 'remove':
+            return self.entity_type == 'relationship' and other.entity_type == 'node'
+        return False
+
+
+class DeploymentModificationBase(ModelBase):
+    """
+    Deployment modification model representation.
+    """
+    __tablename__ = 'deployment_modifications'
+
+    STARTED = 'started'
+    FINISHED = 'finished'
+    ROLLEDBACK = 'rolledback'
+
+    STATES = [STARTED, FINISHED, ROLLEDBACK]
+    END_STATES = [FINISHED, ROLLEDBACK]
+
+    _private_fields = ['deployment_id']
+
+    context = Column(Dict)
+    created_at = Column(DateTime, nullable=False, index=True)
+    ended_at = Column(DateTime, index=True)
+    modified_nodes = Column(Dict)
+    node_instances = Column(Dict)
+    status = Column(Enum(*STATES, name='deployment_modification_status'))
+
+    @declared_attr
+    def deployment_id(cls):
+        return association_proxy('deployment', cls.user_id_column())
+
+    @declared_attr
+    def deployment_fk(cls):
+        return cls.foreign_key('deployments')
+
+    @declared_attr
+    def deployment(cls):
+        return cls.one_to_many_relationship('deployment_fk',
+                                            'Deployment',
+                                            backreference='modifications')
+
+
+class NodeBase(ModelBase):
+    """
+    Node model representation.
+    """
+    __tablename__ = 'nodes'
+
+    # See base class for an explanation on these properties
+    is_id_unique = False
+
+    _private_fields = ['deployment_id', 'host_id']
+
+    @declared_attr
+    def host_id(cls):
+        return association_proxy('host', cls.user_id_column())
+
+    @declared_attr
+    def host_fk(cls):
+        return cls.foreign_key('nodes', nullable=True)
+
+    @declared_attr
+    def host(cls):
+        return cls.relationship_to_self('host_fk')
+
+    @declared_attr
+    def deployment_id(cls):
+        return association_proxy('deployment', cls.user_id_column())
+
+    @declared_attr
+    def deployment_fk(cls):
+        return cls.foreign_key('deployments')
+
+    @declared_attr
+    def deployment(cls):
+        return cls.one_to_many_relationship('deployment_fk', 'Deployment')
+
+    deploy_number_of_instances = Column(Integer, nullable=False)
+    max_number_of_instances = Column(Integer, nullable=False)
+    min_number_of_instances = Column(Integer, nullable=False)
+    number_of_instances = Column(Integer, nullable=False)
+    planned_number_of_instances = Column(Integer, nullable=False)
+    plugins = Column(List)
+    plugins_to_install = Column(Dict)
+    properties = Column(Dict)
+    operations = Column(Dict)
+    type = Column(Text, nullable=False, index=True)
+    type_hierarchy = Column(List)
+
+
+class RelationshipBase(ModelBase):
+    """
+    Relationship model representation.
+    """
+    __tablename__ = 'relationships'
+
+    _private_fields = ['source_node_id', 'target_node_id']
+
+    @declared_attr
+    def source_id(cls):
+        return association_proxy('source_node', cls.user_id_column())
+
+    @declared_attr
+    def source_node_fk(cls):
+        return cls.foreign_key('nodes')
+
+    @declared_attr
+    def source_node(cls):
+        return cls.one_to_many_relationship('source_node_fk',
+                                            'Node',
+                                            backreference='outbound_relationships')
+    @declared_attr
+    def target_name(cls):
+        return association_proxy('target_node', cls.user_id_column())
+
+    @declared_attr
+    def target_node_fk(cls):
+        return cls.foreign_key('nodes')
+
+    @declared_attr
+    def target_node(cls):
+        return cls.one_to_many_relationship('target_node_fk',
+                                            'Node',
+                                            backreference='inbound_relationships')
+
+    source_interfaces = Column(Dict)
+    source_operations = Column(Dict, nullable=False)
+    target_interfaces = Column(Dict)
+    target_operations = Column(Dict, nullable=False)
+    type = Column(String, nullable=False)
+    type_hierarchy = Column(List)
+    properties = Column(Dict)
+
+
+class NodeInstanceBase(ModelBase):
+    """
+    Node instance model representation.
+    """
+    __tablename__ = 'node_instances'
+    _private_fields = ['node_id', 'host_id']
+
+    runtime_properties = Column(Dict)
+    scaling_groups = Column(List)
+    state = Column(Text, nullable=False)
+    version = Column(Integer, default=1)
+
+    @declared_attr
+    def host_id(cls):
+        return association_proxy('host', cls.user_id_column())
+
+    @declared_attr
+    def host_fk(cls):
+        return cls.foreign_key('node_instances', nullable=True)
+
+    @declared_attr
+    def host(cls):
+        return cls.relationship_to_self('host_fk')
+
+    deployment = association_proxy('node', 'deployment')
+    deployment_id = association_proxy('node', 'deployment_id')
+    deployment_name = association_proxy('node', 'deployment_name')
+
+    @declared_attr
+    def node_id(cls):
+        return association_proxy('node', cls.user_id_column())
+
+    @declared_attr
+    def node_fk(cls):
+        return cls.foreign_key('nodes', nullable=True)
+
+    @declared_attr
+    def node(cls):
+        return cls.one_to_many_relationship('node_fk', 'Node')
+
+
+class RelationshipInstanceBase(ModelBase):
+    """
+    Relationship instance model representation.
+    """
+    __tablename__ = 'relationship_instances'
+    _private_fields = ['relationship_storage_id',
+                       'source_node_instance_id',
+                       'target_node_instance_id']
+
+    @declared_attr
+    def source_node_instance_id(cls):
+        return association_proxy('source_node_instance', cls.user_id_column())
+
+    @declared_attr
+    def source_node_instance_fk(cls):
+        return cls.foreign_key('node_instances')
+
+    @declared_attr
+    def source_node_instance(cls):
+        return cls.one_to_many_relationship('source_node_instance_fk',
+                                            'NodeInstance',
+                                            backreference='outbound_relationship_instances')
+
+    @declared_attr
+    def target_node_instance_id(cls):
+        return association_proxy('target_node_instance', cls.user_id_column())
+
+    @declared_attr
+    def target_node_instance_fk(cls):
+        return cls.foreign_key('node_instances')
+
+    @declared_attr
+    def target_node_instance(cls):
+        return cls.one_to_many_relationship('target_node_instance_fk',
+                                            'NodeInstance',
+                                            backreference='inbound_relationship_instances')
+
+    @declared_attr
+    def relationship_fk(cls):
+        return cls.foreign_key('relationships')
+
+    @declared_attr
+    def relationship_id(cls):
+        return association_proxy('relationship', cls.user_id_column())
+
+    @declared_attr
+    def relationship(cls):
+        return cls.one_to_many_relationship('relationship_fk', 'Relationship')
+
+
+class PluginBase(ModelBase):
+    """
+    Plugin model representation.
+    """
+    __tablename__ = 'plugins'
+
+    archive_name = Column(Text, nullable=False, index=True)
+    distribution = Column(Text)
+    distribution_release = Column(Text)
+    distribution_version = Column(Text)
+    excluded_wheels = Column(Dict)
+    package_name = Column(Text, nullable=False, index=True)
+    package_source = Column(Text)
+    package_version = Column(Text)
+    supported_platform = Column(Dict)
+    supported_py_versions = Column(Dict)
+    uploaded_at = Column(DateTime, nullable=False, index=True)
+    wheels = Column(Dict, nullable=False)
+
+
+class TaskBase(ModelBase):
+    """
+    A Model which represents an task
+    """
+    __tablename__ = 'tasks'
+    _private_fields = ['node_instance_id',
+                       'relationship_instance_id',
+                       'execution_id']
+
+    @declared_attr
+    def node_instance_fk(cls):
+        return cls.foreign_key('node_instances', nullable=True)
+
+    @declared_attr
+    def node_instance_id(cls):
+        return association_proxy('node_instance', cls.user_id_column())
+
+    @declared_attr
+    def node_instance(cls):
+        return cls.one_to_many_relationship('node_instance_fk', 'NodeInstance')
+
+    @declared_attr
+    def relationship_instance_fk(cls):
+        return cls.foreign_key('relationship_instances', nullable=True)
+
+    @declared_attr
+    def relationship_instance_id(cls):
+        return association_proxy('relationship_instance', cls.user_id_column())
+
+    @declared_attr
+    def relationship_instance(cls):
+        return cls.one_to_many_relationship('relationship_instance_fk', 'RelationshipInstance')
+
+    PENDING = 'pending'
+    RETRYING = 'retrying'
+    SENT = 'sent'
+    STARTED = 'started'
+    SUCCESS = 'success'
+    FAILED = 'failed'
+    STATES = (
+        PENDING,
+        RETRYING,
+        SENT,
+        STARTED,
+        SUCCESS,
+        FAILED,
+    )
+
+    WAIT_STATES = [PENDING, RETRYING]
+    END_STATES = [SUCCESS, FAILED]
+
+    @orm.validates('max_attempts')
+    def validate_max_attempts(self, _, value):                                  # pylint: disable=no-self-use
+        """Validates that max attempts is either -1 or a positive number"""
+        if value < 1 and value != TaskBase.INFINITE_RETRIES:
+            raise ValueError('Max attempts can be either -1 (infinite) or any positive number. '
+                             'Got {value}'.format(value=value))
+        return value
+
+    INFINITE_RETRIES = -1
+
+    status = Column(Enum(*STATES), name='status', default=PENDING)
+
+    due_at = Column(DateTime, default=datetime.utcnow)
+    started_at = Column(DateTime, default=None)
+    ended_at = Column(DateTime, default=None)
+    max_attempts = Column(Integer, default=1)
+    retry_count = Column(Integer, default=0)
+    retry_interval = Column(Float, default=0)
+    ignore_failure = Column(Boolean, default=False)
+
+    # Operation specific fields
+    operation_mapping = Column(String)
+    inputs = Column(Dict)
+
+    @declared_attr
+    def execution_fk(cls):
+        return cls.foreign_key('executions', nullable=True)
+
+    @declared_attr
+    def execution_id(cls):
+        return association_proxy('execution', cls.user_id_column())
+
+    @declared_attr
+    def execution(cls):
+        return cls.one_to_many_relationship('execution_fk', 'Execution')
+
+    @property
+    def actor(self):
+        """
+        Return the actor of the task
+        :return:
+      `  """
+        return self.node_instance or self.relationship_instance
+
+    @classmethod
+    def as_node_instance(cls, instance_fk, **kwargs):
+        return cls(node_instance_fk=instance_fk, **kwargs)
+
+    @classmethod
+    def as_relationship_instance(cls, instance_fk, **kwargs):
+        return cls(relationship_instance_fk=instance_fk, **kwargs)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/model.py
----------------------------------------------------------------------
diff --git a/aria/storage/model.py b/aria/storage/model.py
new file mode 100644
index 0000000..52f2612
--- /dev/null
+++ b/aria/storage/model.py
@@ -0,0 +1,108 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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.
+
+"""
+Aria's storage.models module
+Path: aria.storage.models
+
+models module holds aria's models.
+
+classes:
+    * Field - represents a single field.
+    * IterField - represents an iterable field.
+    * Model - abstract model implementation.
+    * Snapshot - snapshots implementation model.
+    * Deployment - deployment implementation model.
+    * DeploymentUpdateStep - deployment update step implementation model.
+    * DeploymentUpdate - deployment update implementation model.
+    * DeploymentModification - deployment modification implementation model.
+    * Execution - execution implementation model.
+    * Node - node implementation model.
+    * Relationship - relationship implementation model.
+    * NodeInstance - node instance implementation model.
+    * RelationshipInstance - relationship instance implementation model.
+    * ProviderContext - provider context implementation model.
+    * Plugin - plugin implementation model.
+"""
+
+from sqlalchemy.ext.declarative import declarative_base
+
+from . import structure
+from . import base_model as base
+
+__all__ = (
+    'Blueprint',
+    'Deployment',
+    'DeploymentUpdateStep',
+    'DeploymentUpdate',
+    'DeploymentModification',
+    'Execution',
+    'Node',
+    'Relationship',
+    'NodeInstance',
+    'RelationshipInstance',
+    'Plugin',
+)
+
+
+DeclarativeBase = declarative_base(cls=(structure.ARIADeclarativeBase, structure.ModelIdMixin))
+
+
+class Blueprint(DeclarativeBase, base.BlueprintBase):
+    pass
+
+
+class Deployment(DeclarativeBase, base.DeploymentBase):
+    pass
+
+
+class Execution(DeclarativeBase, base.ExecutionBase):
+    pass
+
+
+class DeploymentUpdate(DeclarativeBase, base.DeploymentUpdateBase):
+    pass
+
+
+class DeploymentUpdateStep(DeclarativeBase, base.DeploymentUpdateStepBase):
+    pass
+
+
+class DeploymentModification(DeclarativeBase, base.DeploymentModificationBase):
+    pass
+
+
+class Node(DeclarativeBase, base.NodeBase):
+    pass
+
+
+class Relationship(DeclarativeBase, base.RelationshipBase):
+    pass
+
+
+class NodeInstance(DeclarativeBase, base.NodeInstanceBase):
+    pass
+
+
+class RelationshipInstance(DeclarativeBase, base.RelationshipInstanceBase):
+    pass
+
+
+class Plugin(DeclarativeBase, base.PluginBase):
+    pass
+
+
+class Task(DeclarativeBase, base.TaskBase):
+    pass

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/models.py
----------------------------------------------------------------------
diff --git a/aria/storage/models.py b/aria/storage/models.py
deleted file mode 100644
index 96af8cc..0000000
--- a/aria/storage/models.py
+++ /dev/null
@@ -1,111 +0,0 @@
-# Licensed to the Apache Software Foundation (ASF) under one or more
-# contributor license agreements.  See the NOTICE file distributed with
-# this work for additional information regarding copyright ownership.
-# The ASF licenses this file to You 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.
-
-"""
-Aria's storage.models module
-Path: aria.storage.models
-
-models module holds aria's models.
-
-classes:
-    * Field - represents a single field.
-    * IterField - represents an iterable field.
-    * Model - abstract model implementation.
-    * Snapshot - snapshots implementation model.
-    * Deployment - deployment implementation model.
-    * DeploymentUpdateStep - deployment update step implementation model.
-    * DeploymentUpdate - deployment update implementation model.
-    * DeploymentModification - deployment modification implementation model.
-    * Execution - execution implementation model.
-    * Node - node implementation model.
-    * Relationship - relationship implementation model.
-    * NodeInstance - node instance implementation model.
-    * RelationshipInstance - relationship instance implementation model.
-    * ProviderContext - provider context implementation model.
-    * Plugin - plugin implementation model.
-"""
-
-from . import structures
-from . import models_base as base
-
-__all__ = (
-    'Blueprint',
-    'Deployment',
-    'DeploymentUpdateStep',
-    'DeploymentUpdate',
-    'DeploymentModification',
-    'Execution',
-    'Node',
-    'Relationship',
-    'NodeInstance',
-    'RelationshipInstance',
-    'ProviderContext',
-    'Plugin',
-)
-
-
-DeclarativeBase = structures.declarative_base(structures.ModelBase)
-
-
-class Blueprint(base.ModelCommon, base.BlueprintBase, DeclarativeBase):
-    pass
-
-
-class Deployment(base.ModelCommon, base.DeploymentBase, DeclarativeBase):
-    pass
-
-
-class Execution(base.ModelCommon, base.ExecutionBase, DeclarativeBase):
-    pass
-
-
-class DeploymentUpdate(base.ModelCommon, base.DeploymentUpdateBase, DeclarativeBase):
-    pass
-
-
-class DeploymentUpdateStep(base.ModelCommon, base.DeploymentUpdateStepBase, DeclarativeBase):
-    pass
-
-
-class DeploymentModification(base.ModelCommon, base.DeploymentModificationBase, DeclarativeBase):
-    pass
-
-
-class Node(base.ModelCommon, base.NodeBase, DeclarativeBase):
-    pass
-
-
-class Relationship(base.ModelCommon, base.RelationshipBase, DeclarativeBase):
-    pass
-
-
-class NodeInstance(base.ModelCommon, base.NodeInstanceBase, DeclarativeBase):
-    pass
-
-
-class RelationshipInstance(base.ModelCommon, base.RelationshipInstanceBase, DeclarativeBase):
-    pass
-
-
-class ProviderContext(base.ModelCommon, base.ProviderContextBase, DeclarativeBase):
-    pass
-
-
-class Plugin(base.ModelCommon, base.PluginBase, DeclarativeBase):
-    pass
-
-
-class Task(base.ModelCommon, base.TaskBase, DeclarativeBase):
-    pass

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/models_base.py
----------------------------------------------------------------------
diff --git a/aria/storage/models_base.py b/aria/storage/models_base.py
deleted file mode 100644
index 95ad01e..0000000
--- a/aria/storage/models_base.py
+++ /dev/null
@@ -1,701 +0,0 @@
-# Licensed to the Apache Software Foundation (ASF) under one or more
-# contributor license agreements.  See the NOTICE file distributed with
-# this work for additional information regarding copyright ownership.
-# The ASF licenses this file to You 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.
-
-"""
-Aria's storage.models module
-Path: aria.storage.models
-
-models module holds aria's models.
-
-classes:
-    * Field - represents a single field.
-    * IterField - represents an iterable field.
-    * Model - abstract model implementation.
-    * Snapshot - snapshots implementation model.
-    * Deployment - deployment implementation model.
-    * DeploymentUpdateStep - deployment update step implementation model.
-    * DeploymentUpdate - deployment update implementation model.
-    * DeploymentModification - deployment modification implementation model.
-    * Execution - execution implementation model.
-    * Node - node implementation model.
-    * Relationship - relationship implementation model.
-    * NodeInstance - node instance implementation model.
-    * RelationshipInstance - relationship instance implementation model.
-    * ProviderContext - provider context implementation model.
-    * Plugin - plugin implementation model.
-"""
-from collections import namedtuple
-from datetime import datetime
-
-from sqlalchemy.ext.associationproxy import association_proxy
-
-from .structures import (
-    Column,
-    Integer,
-    Text,
-    DateTime,
-    Boolean,
-    Enum,
-    String,
-    Float,
-    List,
-    Dict,
-    foreign_key,
-    one_to_many_relationship,
-    relationship_to_self,
-    orm,
-    declared_attr,
-)
-
-__all__ = (
-    'ModelCommon',
-    'BlueprintBase',
-    'DeploymentBase',
-    'DeploymentUpdateStepBase',
-    'DeploymentUpdateBase',
-    'DeploymentModificationBase',
-    'ExecutionBase',
-    'NodeBase',
-    'RelationshipBase',
-    'NodeInstanceBase',
-    'RelationshipInstanceBase',
-    'ProviderContextBase',
-    'PluginBase',
-    'TaskBase'
-)
-
-#pylint: disable=no-self-argument
-
-
-class ModelCommon(object):
-    id = Column(Integer, primary_key=True, autoincrement=True)
-    storage_id_column = 'id'
-    user_id_column = 'name'
-
-
-class BlueprintBase(object):
-    """
-    Blueprint model representation.
-    """
-    __tablename__ = 'blueprints'
-
-    name = Column(Text, index=True)
-    created_at = Column(DateTime, nullable=False, index=True)
-    main_file_name = Column(Text, nullable=False)
-    plan = Column(Dict, nullable=False)
-    updated_at = Column(DateTime)
-    description = Column(Text)
-
-
-class DeploymentBase(object):
-    """
-    Deployment model representation.
-    """
-    __tablename__ = 'deployments'
-
-    _private_fields = ['blueprint_fk']
-
-    name = Column(Text, index=True)
-    created_at = Column(DateTime, nullable=False, index=True)
-    description = Column(Text)
-    inputs = Column(Dict)
-    groups = Column(Dict)
-    permalink = Column(Text)
-    policy_triggers = Column(Dict)
-    policy_types = Column(Dict)
-    outputs = Column(Dict)
-    scaling_groups = Column(List)
-    updated_at = Column(DateTime)
-    workflows = Column(List)
-
-    @declared_attr
-    def blueprint_fk(cls):
-        return foreign_key(cls, 'blueprints', nullable=False)
-
-    @declared_attr
-    def blueprint(cls):
-        return one_to_many_relationship(cls, 'blueprint_fk', 'Blueprint')
-
-    @declared_attr
-    def blueprint_id(cls):
-        return association_proxy('blueprint', cls.user_id_column)
-
-
-class ExecutionBase(object):
-    """
-    Execution model representation.
-    """
-    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
-    id = None
-
-    __tablename__ = 'executions'
-
-    TERMINATED = 'terminated'
-    FAILED = 'failed'
-    CANCELLED = 'cancelled'
-    PENDING = 'pending'
-    STARTED = 'started'
-    CANCELLING = 'cancelling'
-    FORCE_CANCELLING = 'force_cancelling'
-
-    STATES = [TERMINATED, FAILED, CANCELLED, PENDING, STARTED, CANCELLING, FORCE_CANCELLING]
-    END_STATES = [TERMINATED, FAILED, CANCELLED]
-    ACTIVE_STATES = [state for state in STATES if state not in END_STATES]
-
-    VALID_TRANSITIONS = {
-        PENDING: [STARTED, CANCELLED],
-        STARTED: END_STATES + [CANCELLING],
-        CANCELLING: END_STATES
-    }
-
-    @orm.validates('status')
-    def validate_status(self, key, value):
-        """Validation function that verifies execution status transitions are OK"""
-        try:
-            current_status = getattr(self, key)
-        except AttributeError:
-            return
-        valid_transitions = ExecutionBase.VALID_TRANSITIONS.get(current_status, [])
-        if all([current_status is not None,
-                current_status != value,
-                value not in valid_transitions]):
-            raise ValueError('Cannot change execution status from {current} to {new}'.format(
-                current=current_status,
-                new=value))
-        return value
-
-    _private_fields = ['deployment_id', 'blueprint_id']
-
-    created_at = Column(DateTime, index=True)
-    started_at = Column(DateTime, nullable=True, index=True)
-    ended_at = Column(DateTime, nullable=True, index=True)
-    error = Column(Text, nullable=True)
-    is_system_workflow = Column(Boolean, nullable=False, default=False)
-    parameters = Column(Dict)
-    status = Column(Enum(*STATES, name='execution_status'), default=PENDING)
-    workflow_name = Column(Text)
-
-    blueprint = association_proxy('deployment', 'blueprint')
-    blueprint_id = association_proxy('deployment', 'blueprint_id')
-
-    @declared_attr
-    def deployment_fk(cls):
-        return foreign_key(cls, 'deployments', nullable=False)
-
-    @declared_attr
-    def deployment(cls):
-        return one_to_many_relationship(cls, 'deployment_fk', 'Deployment')
-
-    @declared_attr
-    def deployment_id(cls):
-        return association_proxy('deployment', cls.user_id_column)
-
-    def __str__(self):
-        return '<{0} id=`{1}` (status={2})>'.format(
-            self.__class__.__name__,
-            self.id,
-            self.status
-        )
-
-
-class DeploymentUpdateBase(object):
-    """
-    Deployment update model representation.
-    """
-    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
-    steps = None
-
-    __tablename__ = 'deployment_updates'
-
-    _private_fields = ['execution_id', 'deployment_id']
-
-    created_at = Column(DateTime, nullable=False, index=True)
-    deployment_plan = Column(Dict, nullable=False)
-    deployment_update_node_instances = Column(Dict)
-    deployment_update_deployment = Column(Dict)
-    deployment_update_nodes = Column(Dict)
-    modified_entity_ids = Column(Dict)
-    state = Column(Text)
-
-    @declared_attr
-    def execution_fk(cls):
-        return foreign_key(cls, 'executions', nullable=True)
-
-    @declared_attr
-    def execution_id(cls):
-        return association_proxy('executions', cls.user_id_column)
-
-    @declared_attr
-    def execution(cls):
-        return one_to_many_relationship(cls, 'execution_fk', 'Execution')
-
-    @declared_attr
-    def deployment_fk(cls):
-        return foreign_key(cls, 'deployments')
-
-    @declared_attr
-    def deployment_id(cls):
-        return association_proxy('deployment', cls.user_id_column)
-
-    @declared_attr
-    def deployment(cls):
-        return one_to_many_relationship(cls, 'deployment_fk', 'Deployment')
-
-    def to_dict(self, suppress_error=False, **kwargs):
-        dep_update_dict = super(DeploymentUpdateBase, self).to_dict(suppress_error)     #pylint: disable=no-member
-        # Taking care of the fact the DeploymentSteps are _BaseModels
-        dep_update_dict['steps'] = [step.to_dict() for step in self.steps]
-        return dep_update_dict
-
-
-class DeploymentUpdateStepBase(object):
-    """
-    Deployment update step model representation.
-    """
-    # Needed only for pylint. the id will be populated by sqlalcehmy and the proper column.
-    id = None
-
-    __tablename__ = 'deployment_update_steps'
-
-    _action_types = namedtuple('ACTION_TYPES', 'ADD, REMOVE, MODIFY')
-    ACTION_TYPES = _action_types(ADD='add', REMOVE='remove', MODIFY='modify')
-    _entity_types = namedtuple(
-        'ENTITY_TYPES',
-        'NODE, RELATIONSHIP, PROPERTY, OPERATION, WORKFLOW, OUTPUT, DESCRIPTION, GROUP, '
-        'POLICY_TYPE, POLICY_TRIGGER, PLUGIN')
-    ENTITY_TYPES = _entity_types(
-        NODE='node',
-        RELATIONSHIP='relationship',
-        PROPERTY='property',
-        OPERATION='operation',
-        WORKFLOW='workflow',
-        OUTPUT='output',
-        DESCRIPTION='description',
-        GROUP='group',
-        POLICY_TYPE='policy_type',
-        POLICY_TRIGGER='policy_trigger',
-        PLUGIN='plugin'
-    )
-
-    _private_fields = ['deployment_update_id']
-
-    action = Column(Enum(*ACTION_TYPES, name='action_type'), nullable=False)
-    entity_id = Column(Text, nullable=False)
-    entity_type = Column(Enum(*ENTITY_TYPES, name='entity_type'), nullable=False)
-
-    @declared_attr
-    def deployment_update_fk(cls):
-        return foreign_key(cls, 'deployment_updates')
-
-    @declared_attr
-    def deployment_update_id(cls):
-        return association_proxy('deployment_updates', cls.user_id_column)
-
-    @declared_attr
-    def deployment_update(cls):
-        return one_to_many_relationship(cls,
-                                        'deployment_update_fk',
-                                        'DeploymentUpdate',
-                                        backreference='steps')
-
-    def __hash__(self):
-        return hash((self.id, self.entity_id))
-
-    def __lt__(self, other):
-        """
-        the order is 'remove' < 'modify' < 'add'
-        :param other:
-        :return:
-        """
-        if not isinstance(other, self.__class__):
-            return not self >= other
-
-        if self.action != other.action:
-            if self.action == 'remove':
-                return_value = True
-            elif self.action == 'add':
-                return_value = False
-            else:
-                return_value = other.action == 'add'
-            return return_value
-
-        if self.action == 'add':
-            return self.entity_type == 'node' and other.entity_type == 'relationship'
-        if self.action == 'remove':
-            return self.entity_type == 'relationship' and other.entity_type == 'node'
-        return False
-
-
-class DeploymentModificationBase(object):
-    """
-    Deployment modification model representation.
-    """
-    __tablename__ = 'deployment_modifications'
-
-    STARTED = 'started'
-    FINISHED = 'finished'
-    ROLLEDBACK = 'rolledback'
-
-    STATES = [STARTED, FINISHED, ROLLEDBACK]
-    END_STATES = [FINISHED, ROLLEDBACK]
-
-    _private_fields = ['deployment_id']
-
-    context = Column(Dict)
-    created_at = Column(DateTime, nullable=False, index=True)
-    ended_at = Column(DateTime, index=True)
-    modified_nodes = Column(Dict)
-    node_instances = Column(Dict)
-    status = Column(Enum(*STATES, name='deployment_modification_status'))
-
-    @declared_attr
-    def deployment_id(cls):
-        return association_proxy('deployment', cls.user_id_column)
-
-    @declared_attr
-    def deployment_fk(cls):
-        return foreign_key(cls, 'deployments')
-
-    @declared_attr
-    def deployment(cls):
-        return one_to_many_relationship(cls,
-                                        'deployment_fk',
-                                        'Deployment',
-                                        backreference='modifications')
-
-
-class NodeBase(object):
-    """
-    Node model representation.
-    """
-    __tablename__ = 'nodes'
-
-    # See base class for an explanation on these properties
-    is_id_unique = False
-
-    _private_fields = ['deployment_id', 'host_id']
-
-    @declared_attr
-    def host_id(cls):
-        return association_proxy('host', cls.user_id_column)
-
-    @declared_attr
-    def host_fk(cls):
-        return foreign_key(cls, 'nodes', nullable=True)
-
-    @declared_attr
-    def host(cls):
-        return relationship_to_self(cls, 'host_fk')
-
-    @declared_attr
-    def deployment_id(cls):
-        return association_proxy('deployment', cls.user_id_column)
-
-    @declared_attr
-    def deployment_fk(cls):
-        return foreign_key(cls, 'deployments')
-
-    @declared_attr
-    def deployment(cls):
-        return one_to_many_relationship(cls, 'deployment_fk', 'Deployment')
-
-    name = Column(Text, index=True)
-    deploy_number_of_instances = Column(Integer, nullable=False)
-    max_number_of_instances = Column(Integer, nullable=False)
-    min_number_of_instances = Column(Integer, nullable=False)
-    number_of_instances = Column(Integer, nullable=False)
-    planned_number_of_instances = Column(Integer, nullable=False)
-    plugins = Column(List)
-    plugins_to_install = Column(Dict)
-    properties = Column(Dict)
-    operations = Column(Dict)
-    type = Column(Text, nullable=False, index=True)
-    type_hierarchy = Column(List)
-
-
-class RelationshipBase(object):
-    """
-    Relationship model representation.
-    """
-    __tablename__ = 'relationships'
-
-    _private_fields = ['source_node_id', 'target_node_id']
-
-    @declared_attr
-    def source_id(cls):
-        return association_proxy('source_node', cls.user_id_column)
-
-    @declared_attr
-    def source_node_fk(cls):
-        return foreign_key(cls, 'nodes')
-
-    @declared_attr
-    def source_node(cls):
-        return one_to_many_relationship(cls,
-                                        'source_node_fk',
-                                        'Node',
-                                        backreference='outbound_relationships')
-    @declared_attr
-    def target_name(cls):
-        return association_proxy('target_node', cls.user_id_column)
-
-    @declared_attr
-    def target_node_fk(cls):
-        return foreign_key(cls, 'nodes')
-
-    @declared_attr
-    def target_node(cls):
-        return one_to_many_relationship(cls,
-                                        'target_node_fk',
-                                        'Node',
-                                        backreference='inbound_relationships')
-
-    source_interfaces = Column(Dict)
-    source_operations = Column(Dict, nullable=False)
-    target_interfaces = Column(Dict)
-    target_operations = Column(Dict, nullable=False)
-    type = Column(String, nullable=False)
-    type_hierarchy = Column(List)
-    properties = Column(Dict)
-
-
-class NodeInstanceBase(object):
-    """
-    Node instance model representation.
-    """
-    __tablename__ = 'node_instances'
-    _private_fields = ['node_id', 'host_id']
-
-    name = Column(Text, index=True)
-    runtime_properties = Column(Dict)
-    scaling_groups = Column(List)
-    state = Column(Text, nullable=False)
-    version = Column(Integer, default=1)
-
-    @declared_attr
-    def host_id(cls):
-        return association_proxy('host', cls.user_id_column)
-
-    @declared_attr
-    def host_fk(cls):
-        return foreign_key(cls, 'node_instances', nullable=True)
-
-    @declared_attr
-    def host(cls):
-        return relationship_to_self(cls, 'host_fk')
-
-    deployment = association_proxy('node', 'deployment')
-    deployment_id = association_proxy('node', 'deployment_id')
-    deployment_name = association_proxy('node', 'deployment_name')
-
-    @declared_attr
-    def node_id(cls):
-        return association_proxy('node', cls.user_id_column)
-
-    @declared_attr
-    def node_fk(cls):
-        return foreign_key(cls, 'nodes', nullable=True)
-
-    @declared_attr
-    def node(cls):
-        return one_to_many_relationship(cls, 'node_fk', 'Node')
-
-
-class RelationshipInstanceBase(object):
-    """
-    Relationship instance model representation.
-    """
-    __tablename__ = 'relationship_instances'
-    _private_fields = ['relationship_storage_id',
-                       'source_node_instance_id',
-                       'target_node_instance_id']
-
-    @declared_attr
-    def source_node_instance_id(cls):
-        return association_proxy('source_node_instance', cls.user_id_column)
-
-    @declared_attr
-    def source_node_instance_fk(cls):
-        return foreign_key(cls, 'node_instances')
-
-    @declared_attr
-    def source_node_instance(cls):
-        return one_to_many_relationship(cls,
-                                        'source_node_instance_fk',
-                                        'NodeInstance',
-                                        backreference='outbound_relationship_instances')
-
-    @declared_attr
-    def target_node_instance_id(cls):
-        return association_proxy('target_node_instance', cls.user_id_column)
-
-    @declared_attr
-    def target_node_instance_fk(cls):
-        return foreign_key(cls, 'node_instances')
-
-    @declared_attr
-    def target_node_instance(cls):
-        return one_to_many_relationship(cls,
-                                        'target_node_instance_fk',
-                                        'NodeInstance',
-                                        backreference='inbound_relationship_instances')
-
-    @declared_attr
-    def relationship_fk(cls):
-        return foreign_key(cls, 'relationships')
-
-    @declared_attr
-    def relationship_id(cls):
-        return association_proxy('relationship',  cls.user_id_column)
-
-    @declared_attr
-    def relationship(cls):
-        return one_to_many_relationship(cls, 'relationship_fk', 'Relationship')
-
-
-class ProviderContextBase(object):
-    """
-    Provider context model representation.
-    """
-    __tablename__ = 'provider_context'
-
-    name = Column(Text, nullable=True)
-    id = Column(Text, nullable=False)
-    context = Column(Dict, nullable=False)
-
-
-class PluginBase(object):
-    """
-    Plugin model representation.
-    """
-    __tablename__ = 'plugins'
-
-    archive_name = Column(Text, nullable=False, index=True)
-    distribution = Column(Text)
-    distribution_release = Column(Text)
-    distribution_version = Column(Text)
-    excluded_wheels = Column(Dict)
-    package_name = Column(Text, nullable=False, index=True)
-    package_source = Column(Text)
-    package_version = Column(Text)
-    supported_platform = Column(Dict)
-    supported_py_versions = Column(Dict)
-    uploaded_at = Column(DateTime, nullable=False, index=True)
-    wheels = Column(Dict, nullable=False)
-
-
-class TaskBase(object):
-    """
-    A Model which represents an task
-    """
-    __tablename__ = 'tasks'
-    _private_fields = ['node_instance_id',
-                       'relationship_instance_id',
-                       'execution_id']
-
-    @declared_attr
-    def node_instance_fk(cls):
-        return foreign_key(cls, 'node_instances', nullable=True)
-
-    @declared_attr
-    def node_instance_id(cls):
-        return association_proxy('node_instance', cls.user_id_column)
-
-    @declared_attr
-    def node_instance(cls):
-        return one_to_many_relationship(cls, 'node_instance_fk', 'NodeInstance')
-
-    @declared_attr
-    def relationship_instance_fk(cls):
-        return foreign_key(cls, 'relationship_instances', nullable=True)
-
-    @declared_attr
-    def relationship_instance_id(cls):
-        return association_proxy('relationship_instance', cls.user_id_column)
-
-    @declared_attr
-    def relationship_instance(cls):
-        return one_to_many_relationship(cls, 'relationship_instance_fk', 'RelationshipInstance')
-
-    PENDING = 'pending'
-    RETRYING = 'retrying'
-    SENT = 'sent'
-    STARTED = 'started'
-    SUCCESS = 'success'
-    FAILED = 'failed'
-    STATES = (
-        PENDING,
-        RETRYING,
-        SENT,
-        STARTED,
-        SUCCESS,
-        FAILED,
-    )
-
-    WAIT_STATES = [PENDING, RETRYING]
-    END_STATES = [SUCCESS, FAILED]
-
-    @orm.validates('max_attempts')
-    def validate_max_attempts(self, _, value):                                  # pylint: disable=no-self-use
-        """Validates that max attempts is either -1 or a positive number"""
-        if value < 1 and value != TaskBase.INFINITE_RETRIES:
-            raise ValueError('Max attempts can be either -1 (infinite) or any positive number. '
-                             'Got {value}'.format(value=value))
-        return value
-
-    INFINITE_RETRIES = -1
-
-    status = Column(Enum(*STATES), name='status', default=PENDING)
-
-    due_at = Column(DateTime, default=datetime.utcnow)
-    started_at = Column(DateTime, default=None)
-    ended_at = Column(DateTime, default=None)
-    max_attempts = Column(Integer, default=1)
-    retry_count = Column(Integer, default=0)
-    retry_interval = Column(Float, default=0)
-    ignore_failure = Column(Boolean, default=False)
-
-    # Operation specific fields
-    name = Column(String)
-    operation_mapping = Column(String)
-    inputs = Column(Dict)
-
-    @declared_attr
-    def execution_fk(cls):
-        return foreign_key(cls, 'executions', nullable=True)
-
-    @declared_attr
-    def execution_id(cls):
-        return association_proxy('execution', cls.user_id_column)
-
-    @declared_attr
-    def execution(cls):
-        return one_to_many_relationship(cls, 'execution_fk', 'Execution')
-
-    @property
-    def actor(self):
-        """
-        Return the actor of the task
-        :return:
-      `  """
-        return self.node_instance or self.relationship_instance
-
-    @classmethod
-    def as_node_instance(cls, instance_fk, **kwargs):
-        return cls(node_instance_fk=instance_fk, **kwargs)
-
-    @classmethod
-    def as_relationship_instance(cls, instance_fk, **kwargs):
-        return cls(relationship_instance_fk=instance_fk, **kwargs)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/structure.py
----------------------------------------------------------------------
diff --git a/aria/storage/structure.py b/aria/storage/structure.py
new file mode 100644
index 0000000..dd757b7
--- /dev/null
+++ b/aria/storage/structure.py
@@ -0,0 +1,179 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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.
+
+"""
+Aria's storage.structures module
+Path: aria.storage.structures
+
+models module holds aria's models.
+
+classes:
+    * Field - represents a single field.
+    * IterField - represents an iterable field.
+    * PointerField - represents a single pointer field.
+    * IterPointerField - represents an iterable pointers field.
+    * Model - abstract model implementation.
+"""
+
+from sqlalchemy.orm import relationship, backref
+from sqlalchemy import (
+    Column,
+    ForeignKey,
+    Integer,
+    Text
+)
+
+
+class ModelBase(object):
+
+    # overriding pylint stuff
+    __tablename__ = None
+
+    @classmethod
+    def storage_id_column(cls):
+        raise NotImplementedError
+
+    @classmethod
+    def user_id_column(cls):
+        raise NotImplementedError
+
+    @classmethod
+    def _get_cls_by_tablename(cls, tablename):
+        """Return class reference mapped to table.
+
+         :param tablename: String with name of table.
+         :return: Class reference or None.
+         """
+        if tablename in (cls.__name__, cls.__tablename__):
+            return cls
+
+        for table_cls in cls._decl_class_registry.values():
+            if tablename in (getattr(table_cls, '__name__', None),
+                             getattr(table_cls, '__tablename__', None)):
+                return table_cls
+
+    @classmethod
+    def foreign_key(cls, tablename, nullable=False):
+        """Return a ForeignKey object with the relevant
+
+        :param tablename: Unique id column in the parent table
+        :param nullable: Should the column be allowed to remain empty
+        """
+        table = cls._get_cls_by_tablename(tablename)
+        foreign_key_str = '{tablename}.{unique_id}'.format(tablename=tablename,
+                                                           unique_id=table.storage_id_column())
+        return Column(ForeignKey(foreign_key_str, ondelete='CASCADE'), nullable=nullable)
+
+    @classmethod
+    def one_to_many_relationship(cls,
+                                 foreign_key_column,
+                                 parent_class,
+                                 backreference=None):
+        """Return a one-to-many SQL relationship object
+        Meant to be used from inside the *child* object
+
+        :param parent_class: Class of the parent table
+        :param cls: Class of the child table
+        :param foreign_key_column: The column of the foreign key (from the child table)
+        :param backreference: The name to give to the reference to the child (on the parent table)
+        """
+        parent_table = cls._get_cls_by_tablename(parent_class)
+        primaryjoin_str = \
+            '{parent_class_name}.{parent_unique_id} == {child_class.__name__}.{foreign_key_column}'\
+                .format(
+                    parent_class_name=parent_class,
+                    parent_unique_id=parent_table.storage_id_column(),
+                    child_class=cls,
+                    foreign_key_column=foreign_key_column
+                )
+        return relationship(
+            parent_class,
+            primaryjoin=primaryjoin_str,
+            # The following line make sure that when the *parent* is
+            # deleted, all its connected children are deleted as well
+            backref=backref(backreference or cls.__tablename__, cascade='all')
+        )
+
+    @classmethod
+    def relationship_to_self(cls, local_column):
+
+        remote_side_str = '{cls.__name__}.{remote_column}'.format(
+            cls=cls,
+            remote_column=cls.storage_id_column()
+        )
+        primaryjoin_str = '{remote_side_str} == {cls.__name__}.{local_column}'.format(
+            remote_side_str=remote_side_str,
+            cls=cls,
+            local_column=local_column)
+        return relationship(cls.__name__,
+                            primaryjoin=primaryjoin_str,
+                            remote_side=remote_side_str)
+
+
+class ModelIdMixin(object):
+    id = Column(Integer, primary_key=True, autoincrement=True)
+    name = Column(Text, nullable=True, index=True)
+
+    @classmethod
+    def storage_id_column(cls):
+        return 'id'
+
+    @classmethod
+    def user_id_column(cls):
+        return 'name'
+
+
+class ARIADeclarativeBase(object):
+    """
+    Abstract base class for all SQL models that allows [de]serialization
+    """
+    # This would be overridden once the models are created. Created for pylint.
+    __table__ = None
+
+    _private_fields = []
+
+    def to_dict(self, suppress_error=False):
+        """Return a dict representation of the model
+
+        :param suppress_error: If set to True, sets `None` to attributes that
+        it's unable to retrieve (e.g., if a relationship wasn't established
+        yet, and so it's impossible to access a property through it)
+        """
+        if suppress_error:
+            res = dict()
+            for field in self.fields():
+                try:
+                    field_value = getattr(self, field)
+                except AttributeError:
+                    field_value = None
+                res[field] = field_value
+        else:
+            # Can't simply call here `self.to_response()` because inheriting
+            # class might override it, but we always need the same code here
+            res = dict((f, getattr(self, f)) for f in self.fields())
+        return res
+
+    @classmethod
+    def fields(cls):
+        """Return the list of field names for this table
+
+        Mostly for backwards compatibility in the code (that uses `fields`)
+        """
+        return set(cls.__table__.columns.keys()) - set(cls._private_fields)
+
+    def __repr__(self):
+        return '<{__class__.__name__} id=`{id}`>'.format(
+            __class__=self.__class__,
+            id=getattr(self, self.user_id_column()))

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/structures.py
----------------------------------------------------------------------
diff --git a/aria/storage/structures.py b/aria/storage/structures.py
deleted file mode 100644
index 6949305..0000000
--- a/aria/storage/structures.py
+++ /dev/null
@@ -1,267 +0,0 @@
-# Licensed to the Apache Software Foundation (ASF) under one or more
-# contributor license agreements.  See the NOTICE file distributed with
-# this work for additional information regarding copyright ownership.
-# The ASF licenses this file to You 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.
-
-"""
-Aria's storage.structures module
-Path: aria.storage.structures
-
-models module holds aria's models.
-
-classes:
-    * Field - represents a single field.
-    * IterField - represents an iterable field.
-    * PointerField - represents a single pointer field.
-    * IterPointerField - represents an iterable pointers field.
-    * Model - abstract model implementation.
-"""
-import json
-
-from sqlalchemy.ext.mutable import Mutable
-from sqlalchemy.orm import relationship, backref
-# pylint: disable=unused-import
-from sqlalchemy.ext.associationproxy import association_proxy
-from sqlalchemy.ext.declarative import declared_attr, declarative_base
-from sqlalchemy import (
-    schema,
-    VARCHAR,
-    ARRAY,
-    Column,
-    Integer,
-    Text,
-    DateTime,
-    Boolean,
-    Enum,
-    String,
-    PickleType,
-    Float,
-    TypeDecorator,
-    ForeignKey,
-    orm,
-    Table,
-)
-
-from aria.storage import exceptions
-
-
-def _get_cls_by_tablename(cls, tablename):
-    """Return class reference mapped to table.
-
-     :param tablename: String with name of table.
-     :return: Class reference or None.
-     """
-    if tablename in (cls.__name__, cls.__tablename__):
-        return cls
-
-    for table_cls in cls._decl_class_registry.values():
-        if tablename in (getattr(table_cls, '__name__', None),
-                         getattr(table_cls, '__tablename__', None)):
-            return table_cls
-
-
-def foreign_key(child_class, tablename, nullable=False):
-    """Return a ForeignKey object with the relevant
-
-    :param tablename: Unique id column in the parent table
-    :param nullable: Should the column be allowed to remain empty
-    """
-    table = _get_cls_by_tablename(child_class, tablename)
-    foreign_key_str = '{tablename}.{unique_id}'.format(tablename=tablename,
-                                                       unique_id=table.storage_id_column)
-    return Column(ForeignKey(foreign_key_str, ondelete='CASCADE'), nullable=nullable)
-
-
-def one_to_many_relationship(child_class,
-                             foreign_key_column,
-                             parent_class,
-                             backreference=None):
-    """Return a one-to-many SQL relationship object
-    Meant to be used from inside the *child* object
-
-    :param parent_class: Class of the parent table
-    :param child_class: Class of the child table
-    :param foreign_key_column: The column of the foreign key (from the child table)
-    :param backreference: The name to give to the reference to the child (on the parent table)
-    """
-    parent_table = _get_cls_by_tablename(child_class, parent_class)
-    primaryjoin_str = \
-        '{parent_class_name}.{parent_unique_id} == {child_class.__name__}.{foreign_key_column}'\
-        .format(
-            parent_class_name=parent_class,
-            parent_unique_id=parent_table.storage_id_column,
-            child_class=child_class,
-            foreign_key_column=foreign_key_column
-        )
-    return relationship(
-        parent_class,
-        primaryjoin=primaryjoin_str,
-        # The following line make sure that when the *parent* is
-        # deleted, all its connected children are deleted as well
-        backref=backref(backreference or child_class.__tablename__, cascade='all')
-    )
-
-
-def relationship_to_self(cls, local_column):
-
-    remote_side_str = '{cls.__name__}.{remote_column}'.format(cls=cls,
-                                                              remote_column=cls.storage_id_column)
-    primaryjoin_str = '{remote_side_str} == {cls.__name__}.{local_column}'.format(
-        remote_side_str=remote_side_str,
-        cls=cls,
-        local_column=local_column)
-    return relationship(cls.__name__,
-                        primaryjoin=primaryjoin_str,
-                        remote_side=remote_side_str)
-
-
-class ModelBase(object):
-    """
-    Abstract base class for all SQL models that allows [de]serialization
-    """
-    # This would be overridden once the models are created. Created for pylint.
-    __table__ = None
-    id = None
-
-    _private_fields = []
-
-    def to_dict(self, suppress_error=False):
-        """Return a dict representation of the model
-
-        :param suppress_error: If set to True, sets `None` to attributes that
-        it's unable to retrieve (e.g., if a relationship wasn't established
-        yet, and so it's impossible to access a property through it)
-        """
-        if suppress_error:
-            res = dict()
-            for field in self.fields():
-                try:
-                    field_value = getattr(self, field)
-                except AttributeError:
-                    field_value = None
-                res[field] = field_value
-        else:
-            # Can't simply call here `self.to_response()` because inheriting
-            # class might override it, but we always need the same code here
-            res = dict((f, getattr(self, f)) for f in self.fields())
-        return res
-
-    @classmethod
-    def fields(cls):
-        """Return the list of field names for this table
-
-        Mostly for backwards compatibility in the code (that uses `fields`)
-        """
-        return set(cls.__table__.columns.keys()) - set(cls._private_fields)
-
-    def __repr__(self):
-        return '<{0} id=`{1}`>'.format(self.__class__.__name__, self.id)
-
-
-class _MutableType(TypeDecorator):
-    """
-    Dict representation of type.
-    """
-    @property
-    def python_type(self):
-        raise NotImplementedError
-
-    def process_literal_param(self, value, dialect):
-        pass
-
-    impl = VARCHAR
-
-    def process_bind_param(self, value, dialect):
-        if value is not None:
-            value = json.dumps(value)
-        return value
-
-    def process_result_value(self, value, dialect):
-        if value is not None:
-            value = json.loads(value)
-        return value
-
-
-class Dict(_MutableType):
-    @property
-    def python_type(self):
-        return dict
-
-
-class List(_MutableType):
-    @property
-    def python_type(self):
-        return list
-
-
-class _MutableDict(Mutable, dict):
-    """
-    Enables tracking for dict values.
-    """
-    @classmethod
-    def coerce(cls, key, value):
-        "Convert plain dictionaries to MutableDict."
-
-        if not isinstance(value, _MutableDict):
-            if isinstance(value, dict):
-                return _MutableDict(value)
-
-            # this call will raise ValueError
-            try:
-                return Mutable.coerce(key, value)
-            except ValueError as e:
-                raise exceptions.StorageError('SQL Storage error: {0}'.format(str(e)))
-        else:
-            return value
-
-    def __setitem__(self, key, value):
-        "Detect dictionary set events and emit change events."
-
-        dict.__setitem__(self, key, value)
-        self.changed()
-
-    def __delitem__(self, key):
-        "Detect dictionary del events and emit change events."
-
-        dict.__delitem__(self, key)
-        self.changed()
-
-
-class _MutableList(Mutable, list):
-
-    @classmethod
-    def coerce(cls, key, value):
-        "Convert plain dictionaries to MutableDict."
-
-        if not isinstance(value, _MutableList):
-            if isinstance(value, list):
-                return _MutableList(value)
-
-            # this call will raise ValueError
-            try:
-                return Mutable.coerce(key, value)
-            except ValueError as e:
-                raise exceptions.StorageError('SQL Storage error: {0}'.format(str(e)))
-        else:
-            return value
-
-    def __setitem__(self, key, value):
-        list.__setitem__(self, key, value)
-        self.changed()
-
-    def __delitem__(self, key):
-        list.__delitem__(self, key)
-
-
-_MutableDict.associate_with(Dict)
-_MutableList.as_mutable(List)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/aria/storage/type.py
----------------------------------------------------------------------
diff --git a/aria/storage/type.py b/aria/storage/type.py
new file mode 100644
index 0000000..b168b7f
--- /dev/null
+++ b/aria/storage/type.py
@@ -0,0 +1,123 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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 json
+
+from sqlalchemy import (
+    TypeDecorator,
+    VARCHAR
+)
+
+from sqlalchemy.ext import mutable
+
+from . import exceptions
+
+
+class _MutableType(TypeDecorator):
+    """
+    Dict representation of type.
+    """
+    @property
+    def python_type(self):
+        raise NotImplementedError
+
+    def process_literal_param(self, value, dialect):
+        pass
+
+    impl = VARCHAR
+
+    def process_bind_param(self, value, dialect):
+        if value is not None:
+            value = json.dumps(value)
+        return value
+
+    def process_result_value(self, value, dialect):
+        if value is not None:
+            value = json.loads(value)
+        return value
+
+
+class Dict(_MutableType):
+    @property
+    def python_type(self):
+        return dict
+
+
+class List(_MutableType):
+    @property
+    def python_type(self):
+        return list
+
+
+class _MutableDict(mutable.Mutable, dict):
+    """
+    Enables tracking for dict values.
+    """
+    @classmethod
+    def coerce(cls, key, value):
+        "Convert plain dictionaries to MutableDict."
+
+        if not isinstance(value, _MutableDict):
+            if isinstance(value, dict):
+                return _MutableDict(value)
+
+            # this call will raise ValueError
+            try:
+                return mutable.Mutable.coerce(key, value)
+            except ValueError as e:
+                raise exceptions.StorageError('SQL Storage error: {0}'.format(str(e)))
+        else:
+            return value
+
+    def __setitem__(self, key, value):
+        "Detect dictionary set events and emit change events."
+
+        dict.__setitem__(self, key, value)
+        self.changed()
+
+    def __delitem__(self, key):
+        "Detect dictionary del events and emit change events."
+
+        dict.__delitem__(self, key)
+        self.changed()
+
+
+class _MutableList(mutable.Mutable, list):
+
+    @classmethod
+    def coerce(cls, key, value):
+        "Convert plain dictionaries to MutableDict."
+
+        if not isinstance(value, _MutableList):
+            if isinstance(value, list):
+                return _MutableList(value)
+
+            # this call will raise ValueError
+            try:
+                return mutable.Mutable.coerce(key, value)
+            except ValueError as e:
+                raise exceptions.StorageError('SQL Storage error: {0}'.format(str(e)))
+        else:
+            return value
+
+    def __setitem__(self, key, value):
+        list.__setitem__(self, key, value)
+        self.changed()
+
+    def __delitem__(self, key):
+        list.__delitem__(self, key)
+
+
+_MutableDict.associate_with(Dict)
+_MutableList.as_mutable(List)

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/mock/models.py
----------------------------------------------------------------------
diff --git a/tests/mock/models.py b/tests/mock/models.py
index aeda7ca..c14f2f6 100644
--- a/tests/mock/models.py
+++ b/tests/mock/models.py
@@ -15,7 +15,7 @@
 
 from datetime import datetime
 
-from aria.storage import models
+from aria.storage import model
 
 from . import operations
 
@@ -35,7 +35,7 @@ RELATIONSHIP_INSTANCE_NAME = 'relationship_instance'
 
 
 def get_dependency_node(deployment):
-    return models.Node(
+    return model.Node(
         name=DEPENDENCY_NODE_NAME,
         type='test_node_type',
         type_hierarchy=[],
@@ -51,7 +51,7 @@ def get_dependency_node(deployment):
 
 
 def get_dependency_node_instance(dependency_node):
-    return models.NodeInstance(
+    return model.NodeInstance(
         name=DEPENDENCY_NODE_INSTANCE_NAME,
         runtime_properties={'ip': '1.1.1.1'},
         version=None,
@@ -62,7 +62,7 @@ def get_dependency_node_instance(dependency_node):
 
 
 def get_relationship(source=None, target=None):
-    return models.Relationship(
+    return model.Relationship(
         source_node_fk=source.id,
         target_node_fk=target.id,
         source_interfaces={},
@@ -76,7 +76,7 @@ def get_relationship(source=None, target=None):
 
 
 def get_relationship_instance(source_instance, target_instance, relationship):
-    return models.RelationshipInstance(
+    return model.RelationshipInstance(
         relationship_fk=relationship.id,
         target_node_instance_fk=target_instance.id,
         source_node_instance_fk=source_instance.id,
@@ -84,7 +84,7 @@ def get_relationship_instance(source_instance, target_instance, relationship):
 
 
 def get_dependent_node(deployment):
-    return models.Node(
+    return model.Node(
         name=DEPENDENT_NODE_NAME,
         deployment_fk=deployment.id,
         type='test_node_type',
@@ -100,7 +100,7 @@ def get_dependent_node(deployment):
 
 
 def get_dependent_node_instance(dependent_node):
-    return models.NodeInstance(
+    return model.NodeInstance(
         name=DEPENDENT_NODE_INSTANCE_NAME,
         runtime_properties={},
         version=None,
@@ -112,7 +112,7 @@ def get_dependent_node_instance(dependent_node):
 
 def get_blueprint():
     now = datetime.now()
-    return models.Blueprint(
+    return model.Blueprint(
         plan={},
         name=BLUEPRINT_NAME,
         description=None,
@@ -123,9 +123,9 @@ def get_blueprint():
 
 
 def get_execution(deployment):
-    return models.Execution(
+    return model.Execution(
         deployment_fk=deployment.id,
-        status=models.Execution.STARTED,
+        status=model.Execution.STARTED,
         workflow_name=WORKFLOW_NAME,
         started_at=datetime.utcnow(),
         parameters=None
@@ -134,7 +134,7 @@ def get_execution(deployment):
 
 def get_deployment(blueprint):
     now = datetime.utcnow()
-    return models.Deployment(
+    return model.Deployment(
         name=DEPLOYMENT_NAME,
         blueprint_fk=blueprint.id,
         description='',

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/3ac35f63/tests/orchestrator/workflows/core/test_engine.py
----------------------------------------------------------------------
diff --git a/tests/orchestrator/workflows/core/test_engine.py b/tests/orchestrator/workflows/core/test_engine.py
index 44f7cc1..a6b55ba 100644
--- a/tests/orchestrator/workflows/core/test_engine.py
+++ b/tests/orchestrator/workflows/core/test_engine.py
@@ -23,7 +23,7 @@ from aria.orchestrator import (
     workflow,
     operation,
 )
-from aria.storage import models
+from aria.storage import model
 from aria.orchestrator.workflows import (
     api,
     exceptions,
@@ -116,9 +116,7 @@ class BaseTest(object):
 
     @pytest.fixture
     def executor(self):
-        from aria.orchestrator.workflows.executor import blocking
-        result = blocking.CurrentThreadBlockingExecutor()
-        # result = thread.ThreadExecutor()
+        result = thread.ThreadExecutor()
         try:
             yield result
         finally:
@@ -148,7 +146,7 @@ class TestEngine(BaseTest):
         execution = workflow_context.execution
         assert execution.started_at <= execution.ended_at <= datetime.utcnow()
         assert execution.error is None
-        assert execution.status == models.Execution.TERMINATED
+        assert execution.status == model.Execution.TERMINATED
 
     def test_single_task_successful_execution(self, workflow_context, executor):
         @workflow
@@ -177,7 +175,7 @@ class TestEngine(BaseTest):
         execution = workflow_context.execution
         assert execution.started_at <= execution.ended_at <= datetime.utcnow()
         assert execution.error is not None
-        assert execution.status == models.Execution.FAILED
+        assert execution.status == model.Execution.FAILED
 
     def test_two_tasks_execution_order(self, workflow_context, executor):
         @workflow
@@ -238,7 +236,7 @@ class TestCancel(BaseTest):
         execution = workflow_context.execution
         assert execution.started_at <= execution.ended_at <= datetime.utcnow()
         assert execution.error is None
-        assert execution.status == models.Execution.CANCELLED
+        assert execution.status == model.Execution.CANCELLED
 
     def test_cancel_pending_execution(self, workflow_context, executor):
         @workflow
@@ -249,7 +247,7 @@ class TestCancel(BaseTest):
                            executor=executor)
         eng.cancel_execution()
         execution = workflow_context.execution
-        assert execution.status == models.Execution.CANCELLED
+        assert execution.status == model.Execution.CANCELLED
 
 
 class TestRetries(BaseTest):