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Posted to dev@ariatosca.apache.org by em...@apache.org on 2017/02/28 23:01:27 UTC

[5/6] incubator-ariatosca git commit: Major reworking of models to make better use of SqlAlchemy; unfinished work on orchestration models

http://git-wip-us.apache.org/repos/asf/incubator-ariatosca/blob/0150da17/aria/modeling/service.py
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diff --git a/aria/modeling/service.py b/aria/modeling/service.py
new file mode 100644
index 0000000..05c21cc
--- /dev/null
+++ b/aria/modeling/service.py
@@ -0,0 +1,1275 @@
+# 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.
+
+from sqlalchemy import (
+    Column,
+    Text,
+    Integer
+)
+from sqlalchemy import DateTime
+from sqlalchemy.ext.associationproxy import association_proxy
+from sqlalchemy.ext.declarative import declared_attr
+
+from .bases import ModelMixin
+from ..parser import validation
+from ..utils import collections, formatting, console
+
+from . import (
+    utils,
+    types as modeling_types
+)
+
+# pylint: disable=no-self-argument, no-member, abstract-method
+
+
+class _InstanceModelMixin(ModelMixin):
+    """
+    Mixin for :class:`ServiceInstance` models.
+
+    All models support validation, diagnostic dumping, and representation as
+    raw data (which can be translated into JSON or YAML) via :code:`as_raw`.
+    """
+
+    @property
+    def as_raw(self):
+        raise NotImplementedError
+
+    def validate(self, context):
+        pass
+
+    def coerce_values(self, context, container, report_issues):
+        pass
+
+    def dump(self, context):
+        pass
+
+
+class ServiceBase(_InstanceModelMixin):
+    """
+    A service instance is an instance of a :class:`ServiceTemplate`.
+
+    You will usually not create it programmatically, but instead instantiate it from the template.
+
+    :ivar description: Human-readable description
+    :ivar meta_data: Dict of :class:`Metadata`
+    :ivar nodes: Dict of :class:`Node`
+    :ivar groups: Dict of :class:`Group`
+    :ivar policies: Dict of :class:`Policy`
+    :ivar substitution: :class:`Substitution`
+    :ivar inputs: Dict of :class:`Parameter`
+    :ivar outputs: Dict of :class:`Parameter`
+    :ivar operations: Dict of :class:`Operation`
+    """
+
+    __tablename__ = 'service' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['substituion_fk',
+                          'service_template_fk']
+
+    description = Column(Text)
+
+    @declared_attr
+    def meta_data(cls):
+        # Warning! We cannot use the attr name "metadata" because it's used by SqlAlchemy!
+        return cls.many_to_many_relationship('metadata', key_column_name='name')
+
+    @declared_attr
+    def nodes(cls):
+        return cls.one_to_many_relationship('node')
+
+    @declared_attr
+    def groups(cls):
+        return cls.one_to_many_relationship('group')
+
+    @declared_attr
+    def policies(cls):
+        return cls.one_to_many_relationship('policy')
+
+    @declared_attr
+    def substitution(cls):
+        return cls.one_to_one_relationship('substitution')
+
+    @declared_attr
+    def inputs(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='inputs',
+                                             key_column_name='name')
+
+    @declared_attr
+    def outputs(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='outputs',
+                                             key_column_name='name')
+
+    @declared_attr
+    def operations(cls):
+        return cls.one_to_many_relationship('operation', key_column_name='name')
+
+    @declared_attr
+    def service_template(cls):
+        return cls.many_to_one_relationship('service_template')
+
+    # region orchestrator required columns
+
+    created_at = Column(DateTime, nullable=False, index=True)
+    updated_at = Column(DateTime)
+    permalink = Column(Text)
+    scaling_groups = Column(modeling_types.Dict)
+    workflows = Column(modeling_types.Dict)
+
+    @declared_attr
+    def service_template_name(cls):
+        return association_proxy('service_template', 'name')
+
+    # endregion
+
+    # region foreign keys
+
+    # Service one-to-one to Substitution
+    @declared_attr
+    def substitution_fk(cls):
+        return cls.foreign_key('substitution', nullable=True)
+
+    # Service many-to-one to ServiceTemplate
+    @declared_attr
+    def service_template_fk(cls):
+        return cls.foreign_key('service_template')
+
+    # endregion
+
+    def satisfy_requirements(self, context):
+        satisfied = True
+        for node in self.nodes:
+            if not node.satisfy_requirements(context):
+                satisfied = False
+        return satisfied
+
+    def validate_capabilities(self, context):
+        satisfied = True
+        for node in self.nodes:
+            if not node.validate_capabilities(context):
+                satisfied = False
+        return satisfied
+
+    def find_nodes(self, node_template_name):
+        nodes = []
+        for node in self.nodes:
+            if node.node_template.name == node_template_name:
+                nodes.append(node)
+        return collections.FrozenList(nodes)
+
+    def get_node_ids(self, node_template_name):
+        return collections.FrozenList((node.name for node in self.find_nodes(node_template_name)))
+
+    def find_groups(self, group_template_name):
+        groups = []
+        for group in self.groups:
+            if group.template_name == group_template_name:
+                groups.append(group)
+        return collections.FrozenList(groups)
+
+    def get_group_ids(self, group_template_name):
+        return collections.FrozenList((group.name for group in self.find_groups(group_template_name)))
+
+    def is_node_a_target(self, context, target_node):
+        for node in self.nodes:
+            if self._is_node_a_target(context, node, target_node):
+                return True
+        return False
+
+    def _is_node_a_target(self, context, source_node, target_node):
+        if source_node.relationships:
+            for relationship in source_node.relationships:
+                if relationship.target_node_id == target_node.name:
+                    return True
+                else:
+                    node = context.modeling.instance.nodes.get(relationship.target_node_id)
+                    if node is not None:
+                        if self._is_node_a_target(context, node, target_node):
+                            return True
+        return False
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('description', self.description),
+            ('metadata', formatting.as_raw_dict(self.meta_data)),
+            ('nodes', formatting.as_raw_list(self.nodes)),
+            ('groups', formatting.as_raw_list(self.groups)),
+            ('policies', formatting.as_raw_list(self.policies)),
+            ('substitution', formatting.as_raw(self.substitution)),
+            ('inputs', formatting.as_raw_dict(self.inputs)),
+            ('outputs', formatting.as_raw_dict(self.outputs)),
+            ('operations', formatting.as_raw_list(self.operations))))
+
+    def validate(self, context):
+        utils.validate_dict_values(context, self.meta_data)
+        utils.validate_list_values(context, self.nodes)
+        utils.validate_list_values(context, self.groups)
+        utils.validate_list_values(context, self.policies)
+        if self.substitution is not None:
+            self.substitution.validate(context)
+        utils.validate_dict_values(context, self.inputs)
+        utils.validate_dict_values(context, self.outputs)
+        utils.validate_dict_values(context, self.operations)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.meta_data, report_issues)
+        utils.coerce_list_values(context, container, self.nodes, report_issues)
+        utils.coerce_list_values(context, container, self.groups, report_issues)
+        utils.coerce_list_values(context, container, self.policies, report_issues)
+        if self.substitution is not None:
+            self.substitution.coerce_values(context, container, report_issues)
+        utils.coerce_dict_values(context, container, self.inputs, report_issues)
+        utils.coerce_dict_values(context, container, self.outputs, report_issues)
+        utils.coerce_dict_values(context, container, self.operations, report_issues)
+
+    def dump(self, context):
+        if self.description is not None:
+            console.puts(context.style.meta(self.description))
+        utils.dump_parameters(context, self.meta_data, 'Metadata')
+        for node in self.nodes:
+            node.dump(context)
+        for group in self.groups:
+            group.dump(context)
+        for policy in self.policies:
+            policy.dump(context)
+        if self.substitution is not None:
+            self.substitution.dump(context)
+        utils.dump_parameters(context, self.inputs, 'Inputs')
+        utils.dump_parameters(context, self.outputs, 'Outputs')
+        utils.dump_dict_values(context, self.operations, 'Operations')
+
+    def dump_graph(self, context):
+        for node in self.nodes.itervalues():
+            if not self.is_node_a_target(context, node):
+                self._dump_graph_node(context, node)
+
+    def _dump_graph_node(self, context, node):
+        console.puts(context.style.node(node.name))
+        if node.relationships:
+            with context.style.indent:
+                for relationship in node.relationships:
+                    relationship_name = (context.style.node(relationship.template_name)
+                                         if relationship.template_name is not None
+                                         else context.style.type(relationship.type_name))
+                    capability_name = (context.style.node(relationship.target_capability_name)
+                                       if relationship.target_capability_name is not None
+                                       else None)
+                    if capability_name is not None:
+                        console.puts('-> {0} {1}'.format(relationship_name, capability_name))
+                    else:
+                        console.puts('-> {0}'.format(relationship_name))
+                    target_node = self.nodes.get(relationship.target_node_id)
+                    with console.indent(3):
+                        self._dump_graph_node(context, target_node)
+
+
+class NodeBase(_InstanceModelMixin):
+    """
+    An instance of a :class:`NodeTemplate`.
+
+    Nodes may have zero or more :class:`Relationship` instances to other nodes.
+
+    :ivar name: Unique ID (prefixed with the template name)
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar properties: Dict of :class:`Parameter`
+    :ivar interfaces: Dict of :class:`Interface`
+    :ivar artifacts: Dict of :class:`Artifact`
+    :ivar capabilities: Dict of :class:`CapabilityTemplate`
+    :ivar relationships: List of :class:`Relationship`
+    """
+
+    __tablename__ = 'node' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['host_fk',
+                          'service_fk',
+                          'node_template_fk']
+
+    type_name = Column(Text)
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    @declared_attr
+    def interfaces(cls):
+        return cls.one_to_many_relationship('interface', key_column_name='name')
+
+    @declared_attr
+    def artifacts(cls):
+        return cls.one_to_many_relationship('artifact', key_column_name='name')
+
+    @declared_attr
+    def capabilities(cls):
+        return cls.one_to_many_relationship('capability', key_column_name='name')
+
+    @declared_attr
+    def outbound_relationships(cls):
+        return cls.one_to_many_relationship('relationship',
+                                            foreign_key_name='source_node_fk',
+                                            backreference='source_node')
+
+    @declared_attr
+    def inbound_relationships(cls):
+        return cls.one_to_many_relationship('relationship',
+                                            foreign_key_name='target_node_fk',
+                                            backreference='target_node')
+
+    @declared_attr
+    def host(cls):
+        return cls.relationship_to_self('host_fk')
+
+    @declared_attr
+    def node_template(cls):
+        return cls.many_to_one_relationship('node_template')
+
+    # region orchestrator required columns
+
+    runtime_properties = Column(modeling_types.Dict)
+    scaling_groups = Column(modeling_types.List)
+    state = Column(Text, nullable=False)
+    version = Column(Integer, default=1)
+
+    @declared_attr
+    def plugins(cls):
+        return association_proxy('node_template', 'plugins')
+
+    @declared_attr
+    def service_name(cls):
+        return association_proxy('service', 'name')
+
+    @property
+    def ip(self):
+        # TODO: totally broken
+        if not self.host_fk:
+            return None
+        host_node = self.host
+        if 'ip' in host_node.runtime_properties:  # pylint: disable=no-member
+            return host_node.runtime_properties['ip']  # pylint: disable=no-member
+        host_node = host_node.node_template  # pylint: disable=no-member
+        host_ip_property = [prop for prop in host_node.properties if prop.name == 'ip']
+        if host_ip_property:
+            return host_ip_property[0].value
+        return None
+
+    # endregion
+
+    # region foreign_keys
+
+    # Node one-to-one to Node
+    @declared_attr
+    def host_fk(cls):
+        return cls.foreign_key('node', nullable=True)
+
+    # Service one-to-many to Node
+    @declared_attr
+    def service_fk(cls):
+        return cls.foreign_key('service')
+
+    # Node many-to-one to NodeTemplate
+    @declared_attr
+    def node_template_fk(cls):
+        return cls.foreign_key('node_template')
+
+    # endregion
+
+    def satisfy_requirements(self, context):
+        node_template = self.node_template
+        satisfied = True
+        for requirement_template in node_template.requirement_templates:
+            # Find target template
+            target_node_template, target_node_capability = \
+                requirement_template.find_target(context, node_template)
+            if target_node_template is not None:
+                satisfied = self._satisfy_capability(context,
+                                                     target_node_capability,
+                                                     target_node_template,
+                                                     requirement_template)
+            else:
+                context.validation.report('requirement "{0}" of node "{1}" has no target node '
+                                          'template'.format(requirement_template.name, self.name),
+                                          level=validation.Issue.BETWEEN_INSTANCES)
+                satisfied = False
+        return satisfied
+
+    def _satisfy_capability(self, context, target_node_capability, target_node_template,
+                            requirement_template):
+        from . import models
+        # Find target nodes
+        target_nodes = context.modeling.instance.find_nodes(target_node_template.name)
+        if target_nodes:
+            target_node = None
+            target_capability = None
+
+            if target_node_capability is not None:
+                # Relate to the first target node that has capacity
+                for node in target_nodes:
+                    target_capability = node.capabilities.get(target_node_capability.name)
+                    if target_capability.relate():
+                        target_node = node
+                        break
+            else:
+                # Use first target node
+                target_node = target_nodes[0]
+
+            if target_node is not None:
+                relationship = models.Relationship(
+                    name=requirement_template.name,
+                    requirement_template=requirement_template,
+                    target_node=target_node,
+                    capability=target_capability
+                )
+                self.outbound_relationships.append(relationship)
+            else:
+                context.validation.report('requirement "{0}" of node "{1}" targets node '
+                                          'template "{2}" but its instantiated nodes do not '
+                                          'have enough capacity'.format(
+                                              requirement_template.name,
+                                              self.name,
+                                              target_node_template.name),
+                                          level=validation.Issue.BETWEEN_INSTANCES)
+                return False
+        else:
+            context.validation.report('requirement "{0}" of node "{1}" targets node template '
+                                      '"{2}" but it has no instantiated nodes'.format(
+                                          requirement_template.name,
+                                          self.name,
+                                          target_node_template.name),
+                                      level=validation.Issue.BETWEEN_INSTANCES)
+            return False
+
+    def validate_capabilities(self, context):
+        satisfied = False
+        for capability in self.capabilities.itervalues():
+            if not capability.has_enough_relationships:
+                context.validation.report('capability "{0}" of node "{1}" requires at least {2:d} '
+                                          'relationships but has {3:d}'.format(
+                                              capability.name,
+                                              self.name,
+                                              capability.min_occurrences,
+                                              capability.occurrences),
+                                          level=validation.Issue.BETWEEN_INSTANCES)
+                satisfied = False
+        return satisfied
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('type_name', self.type_name),
+            ('properties', formatting.as_raw_dict(self.properties)),
+            ('interfaces', formatting.as_raw_list(self.interfaces)),
+            ('artifacts', formatting.as_raw_list(self.artifacts)),
+            ('capabilities', formatting.as_raw_list(self.capabilities)),
+            ('relationships', formatting.as_raw_list(self.outbound_relationships))))
+
+    def validate(self, context):
+        if len(self.name) > context.modeling.id_max_length:
+            context.validation.report('"{0}" has an ID longer than the limit of {1:d} characters: '
+                                      '{2:d}'.format(
+                                            self.name,
+                                            context.modeling.id_max_length,
+                                            len(self.name)),
+                                      level=validation.Issue.BETWEEN_INSTANCES)
+
+        # TODO: validate that node template is of type?
+
+        utils.validate_dict_values(context, self.properties)
+        utils.validate_dict_values(context, self.interfaces)
+        utils.validate_dict_values(context, self.artifacts)
+        utils.validate_dict_values(context, self.capabilities)
+        utils.validate_list_values(context, self.outbound_relationships)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, self, self.properties, report_issues)
+        utils.coerce_dict_values(context, self, self.interfaces, report_issues)
+        utils.coerce_dict_values(context, self, self.artifacts, report_issues)
+        utils.coerce_dict_values(context, self, self.capabilities, report_issues)
+        utils.coerce_list_values(context, self, self.outbound_relationships, report_issues)
+
+    def dump(self, context):
+        console.puts('Node: {0}'.format(context.style.node(self.name)))
+        with context.style.indent:
+            console.puts('Template: {0}'.format(context.style.node(self.node_template.name)))
+            console.puts('Type: {0}'.format(context.style.type(self.type_name)))
+            utils.dump_parameters(context, self.properties)
+            utils.dump_interfaces(context, self.interfaces)
+            utils.dump_dict_values(context, self.artifacts, 'Artifacts')
+            utils.dump_dict_values(context, self.capabilities, 'Capabilities')
+            utils.dump_list_values(context, self.outbound_relationships, 'Relationships')
+
+
+class GroupBase(_InstanceModelMixin):
+    """
+    An instance of a :class:`GroupTemplate`.
+
+    :ivar name: Unique ID (prefixed with the template name)
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar template_name: Must be represented in the :class:`ServiceTemplate`
+    :ivar properties: Dict of :class:`Parameter`
+    :ivar interfaces: Dict of :class:`Interface`
+    :ivar member_node_ids: Must be represented in the :class:`ServiceInstance`
+    :ivar member_group_ids: Must be represented in the :class:`ServiceInstance`
+    """
+
+    __tablename__ = 'group' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['service_fk',
+                          'group_template_fk']
+
+    type_name = Column(Text)
+    template_name = Column(Text)
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    @declared_attr
+    def interfaces(cls):
+        return cls.one_to_many_relationship('interface', key_column_name='name')
+
+    member_node_ids = Column(modeling_types.StrictList(basestring))
+    member_group_ids = Column(modeling_types.StrictList(basestring))
+
+    @declared_attr
+    def group_template(cls):
+        return cls.many_to_one_relationship('group_template')
+
+    # region foreign_keys
+
+    # Service one-to-many to Group
+    @declared_attr
+    def service_fk(cls):
+        return cls.foreign_key('service')
+
+    # Group many-to-one to GroupTemplate
+    @declared_attr
+    def group_template_fk(cls):
+        return cls.foreign_key('group_template')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('type_name', self.type_name),
+            ('template_name', self.template_name),
+            ('properties', formatting.as_raw_dict(self.properties)),
+            ('interfaces', formatting.as_raw_list(self.interfaces)),
+            ('member_node_ids', self.member_node_ids),
+            ('member_group_ids', self.member_group_ids)))
+
+    def validate(self, context):
+        if context.modeling.group_types.get_descendant(self.type_name) is None:
+            context.validation.report('group "{0}" has an unknown type: {1}'.format(
+                                        self.name,  # pylint: disable=no-member
+                                        # TODO fix self.name reference
+                                        formatting.safe_repr(self.type_name)),
+                                      level=validation.Issue.BETWEEN_TYPES)
+
+        utils.validate_dict_values(context, self.properties)
+        utils.validate_dict_values(context, self.interfaces)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.properties, report_issues)
+        utils.coerce_dict_values(context, container, self.interfaces, report_issues)
+
+    def dump(self, context):
+        console.puts('Group: {0}'.format(context.style.node(self.name)))
+        with context.style.indent:
+            console.puts('Type: {0}'.format(context.style.type(self.type_name)))
+            console.puts('Template: {0}'.format(context.style.type(self.template_name)))
+            utils.dump_parameters(context, self.properties)
+            utils.dump_interfaces(context, self.interfaces)
+            if self.member_node_ids:
+                console.puts('Member nodes:')
+                with context.style.indent:
+                    for node_id in self.member_node_ids:
+                        console.puts(context.style.node(node_id))
+
+
+class PolicyBase(_InstanceModelMixin):
+    """
+    An instance of a :class:`PolicyTemplate`.
+
+    :ivar name: Name
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar properties: Dict of :class:`Parameter`
+    :ivar target_node_ids: Must be represented in the :class:`ServiceInstance`
+    :ivar target_group_ids: Must be represented in the :class:`ServiceInstance`
+    """
+
+    __tablename__ = 'policy' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['service_fk',
+                          'policy_template_fk']
+
+    type_name = Column(Text)
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    target_node_ids = Column(modeling_types.StrictList(basestring))
+    target_group_ids = Column(modeling_types.StrictList(basestring))
+
+    @declared_attr
+    def policy_template(cls):
+        return cls.many_to_one_relationship('policy_template')
+
+    # region foreign_keys
+
+    # Service one-to-many to Policy
+    @declared_attr
+    def service_fk(cls):
+        return cls.foreign_key('service')
+
+    # Policy many-to-one to PolicyTemplate
+    @declared_attr
+    def policy_template_fk(cls):
+        return cls.foreign_key('policy_template')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('type_name', self.type_name),
+            ('properties', formatting.as_raw_dict(self.properties)),
+            ('target_node_ids', self.target_node_ids),
+            ('target_group_ids', self.target_group_ids)))
+
+    def validate(self, context):
+        if context.modeling.policy_types.get_descendant(self.type_name) is None:
+            context.validation.report('policy "{0}" has an unknown type: {1}'.format(
+                                        self.name, formatting.safe_repr(self.type_name)),
+                                      level=validation.Issue.BETWEEN_TYPES)
+
+        utils.validate_dict_values(context, self.properties)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.properties, report_issues)
+
+    def dump(self, context):
+        console.puts('Policy: {0}'.format(context.style.node(self.name)))
+        with context.style.indent:
+            console.puts('Type: {0}'.format(context.style.type(self.type_name)))
+            utils.dump_parameters(context, self.properties)
+            if self.target_node_ids:
+                console.puts('Target nodes:')
+                with context.style.indent:
+                    for node_id in self.target_node_ids:
+                        console.puts(context.style.node(node_id))
+            if self.target_group_ids:
+                console.puts('Target groups:')
+                with context.style.indent:
+                    for group_id in self.target_group_ids:
+                        console.puts(context.style.node(group_id))
+
+
+class SubstitutionBase(_InstanceModelMixin):
+    """
+    An instance of a :class:`SubstitutionTemplate`.
+
+    :ivar node_type_name: Must be represented in the :class:`ModelingContext`
+    :ivar mappings: Dict of :class:` SubstitutionMapping`
+    """
+
+    __tablename__ = 'substitution' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['substitution_template_fk']
+
+    node_type_name = Column(Text)
+
+    @declared_attr
+    def mappings(cls):
+        return cls.one_to_many_relationship('substitution_mapping', key_column_name='name')
+
+    @declared_attr
+    def substitution_template(cls):
+        return cls.many_to_one_relationship('substitution_template')
+
+    # region foreign_keys
+
+    # Substitution many-to-one to SubstitutionTemplate
+    @declared_attr
+    def substitution_template_fk(cls):
+        return cls.foreign_key('substitution_template')
+
+    # endregion
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('node_type_name', self.node_type_name),
+            ('mappings', formatting.as_raw_dict(self.mappings))))
+
+    def validate(self, context):
+        if context.modeling.node_types.get_descendant(self.node_type_name) is None:
+            context.validation.report('substitution "{0}" has an unknown type: {1}'.format(
+                                        self.name,  # pylint: disable=no-member
+                                        # TODO fix self.name reference
+                                        formatting.safe_repr(self.node_type_name)),
+                                      level=validation.Issue.BETWEEN_TYPES)
+
+        utils.validate_dict_values(context, self.mappings)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.mappings, report_issues)
+
+    def dump(self, context):
+        console.puts('Substitution:')
+        with context.style.indent:
+            console.puts('Node type: {0}'.format(context.style.type(self.node_type_name)))
+            utils.dump_dict_values(context, self.mappings, 'Mappings')
+
+
+class SubstitutionMappingBase(_InstanceModelMixin):
+    """
+    An instance of a :class:`SubstitutionMappingTemplate`.
+
+    :ivar mapped_name: Exposed capability or requirement name
+    :ivar node_id: Must be represented in the :class:`ServiceInstance`
+    :ivar name: Name of capability or requirement at the node
+    """
+
+    __tablename__ = 'substitution_mapping' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['substitution_fk']
+
+    mapped_name = Column(Text)
+    node_id = Column(Text)
+
+    # region foreign keys
+
+    # Substitution one-to-many to SubstitutionMapping
+    @declared_attr
+    def substitution_fk(cls):
+        return cls.foreign_key('substitution')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('mapped_name', self.mapped_name),
+            ('node_id', self.node_id),
+            ('name', self.name)))
+
+    def dump(self, context):
+        console.puts('{0} -> {1}.{2}'.format(
+                        context.style.node(self.mapped_name),
+                        context.style.node(self.node_id),
+                        context.style.node(self.name)))
+
+
+class RelationshipBase(_InstanceModelMixin):
+    """
+    Connects :class:`Node` to another node.
+
+    An instance of a :class:`RelationshipTemplate`.
+
+    :ivar name: Name (usually the name of the requirement at the source node template)
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar properties: Dict of :class:`Parameter`
+    :ivar interfaces: Dict of :class:`Interface`
+    """
+
+    __tablename__ = 'relationship' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['source_node_fk',
+                          'target_node_fk',
+                          'capability_fk',
+                          'requirement_template_fk',
+                          'relationship_template_fk']
+
+    type_name = Column(Text)
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    @declared_attr
+    def interfaces(cls):
+        return cls.one_to_many_relationship('interface', key_column_name='name')
+
+    @declared_attr
+    def capability(cls):
+        return cls.one_to_one_relationship('capability')
+
+    @declared_attr
+    def requirement_template(cls):
+        return cls.many_to_one_relationship('requirement_template')
+
+    @declared_attr
+    def relationship_template(cls):
+        return cls.many_to_one_relationship('relationship_template')
+
+    # region orchestrator required columns
+
+    source_position = Column(Integer) # ???
+    target_position = Column(Integer) # ???
+
+    # endregion
+
+    # region foreign keys
+
+    # Node one-to-many to Relationship
+    @declared_attr
+    def source_node_fk(cls):
+        return cls.foreign_key('node')
+
+    # Node one-to-many to Relationship
+    @declared_attr
+    def target_node_fk(cls):
+        return cls.foreign_key('node')
+
+    # Relationship one-to-one to Capability
+    @declared_attr
+    def capability_fk(cls):
+        return cls.foreign_key('capability', nullable=True)
+
+    # Relationship many-to-one to RequirementTemplate
+    @declared_attr
+    def requirement_template_fk(cls):
+        return cls.foreign_key('requirement_template')
+
+    # Relationship many-to-one to RelationshipTemplate
+    @declared_attr
+    def relationship_template_fk(cls):
+        return cls.foreign_key('relationship_template', nullable=True)
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('target_node_id', self.target_node.name),
+            ('type_name', self.type_name),
+            ('template_name', self.template_name),
+            ('properties', formatting.as_raw_dict(self.properties)),
+            ('interfaces', formatting.as_raw_list(self.interfaces))))
+
+    def validate(self, context):
+        if self.type_name:
+            if context.modeling.relationship_types.get_descendant(self.type_name) is None:
+                context.validation.report('relationship "{0}" has an unknown type: {1}'.format(
+                                            self.name,
+                                            formatting.safe_repr(self.type_name)),
+                                          level=validation.Issue.BETWEEN_TYPES)
+        utils.validate_dict_values(context, self.properties)
+        utils.validate_dict_values(context, self.interfaces)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.properties, report_issues)
+        utils.coerce_dict_values(context, container, self.interfaces, report_issues)
+
+    def dump(self, context):
+        if self.name:
+            console.puts('{0} ->'.format(context.style.node(self.name)))
+        else:
+            console.puts('->')
+        with context.style.indent:
+            console.puts('Node: {0}'.format(context.style.node(self.target_node.name)))
+            if self.type_name is not None:
+                console.puts('Relationship type: {0}'.format(context.style.type(self.type_name)))
+            #if self.template_name is not None:
+            #    console.puts('Relationship template: {0}'.format(
+            #        context.style.node(self.template_name)))
+            utils.dump_parameters(context, self.properties)
+            utils.dump_interfaces(context, self.interfaces, 'Interfaces')
+
+
+class CapabilityBase(_InstanceModelMixin):
+    """
+    A capability of a :class:`Node`.
+
+    An instance of a :class:`CapabilityTemplate`.
+
+    :ivar name: Name
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar min_occurrences: Minimum number of requirement matches required
+    :ivar max_occurrences: Maximum number of requirement matches allowed
+    :ivar properties: Dict of :class:`Parameter`
+    """
+
+    __tablename__ = 'capability' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['node_fk',
+                          'capability_template_fk']
+
+    type_name = Column(Text)
+    min_occurrences = Column(Integer, default=None) # optional
+    max_occurrences = Column(Integer, default=None) # optional
+    occurrences = Column(Integer, default=0)
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    @declared_attr
+    def capability_template(cls):
+        return cls.many_to_one_relationship('capability_template')
+
+    # region foreign_keys
+
+    # Node one-to-many to Capability
+    @declared_attr
+    def node_fk(cls):
+        return cls.foreign_key('node')
+
+    # Capability many-to-one to CapabilityTemplate
+    @declared_attr
+    def capability_template_fk(cls):
+        return cls.foreign_key('capability_template')
+
+    # endregion
+
+    @property
+    def has_enough_relationships(self):
+        if self.min_occurrences is not None:
+            return self.occurrences >= self.min_occurrences
+        return True
+
+    def relate(self):
+        if self.max_occurrences is not None:
+            if self.occurrences == self.max_occurrences:
+                return False
+        self.occurrences += 1
+        return True
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('type_name', self.type_name),
+            ('properties', formatting.as_raw_dict(self.properties))))
+
+    def validate(self, context):
+        if context.modeling.capability_types.get_descendant(self.type_name) is None:
+            context.validation.report('capability "{0}" has an unknown type: {1}'.format(
+                                        self.name,
+                                        formatting.safe_repr(self.type_name)),
+                                      level=validation.Issue.BETWEEN_TYPES)
+
+        utils.validate_dict_values(context, self.properties)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.properties, report_issues)
+
+    def dump(self, context):
+        console.puts(context.style.node(self.name))
+        with context.style.indent:
+            console.puts('Type: {0}'.format(context.style.type(self.type_name)))
+            console.puts('Occurrences: {0:d} ({1:d}{2})'.format(
+                            self.occurrences,
+                            self.min_occurrences or 0,
+                            ' to {0:d}'.format(self.max_occurrences)
+                                if self.max_occurrences is not None
+                                else ' or more'))
+            utils.dump_parameters(context, self.properties)
+
+
+class InterfaceBase(_InstanceModelMixin):
+    """
+    A typed set of :class:`Operation`.
+
+    :ivar name: Name
+    :ivar description: Description
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar inputs: Dict of :class:`Parameter`
+    :ivar operations: Dict of :class:`Operation`
+    """
+
+    __tablename__ = 'interface' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['node_fk',
+                          'group_fk',
+                          'relationship_fk',
+                          'interface_template_fk']
+
+    description = Column(Text)
+    type_name = Column(Text)
+
+    @declared_attr
+    def inputs(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='inputs',
+                                             key_column_name='name')
+
+    @declared_attr
+    def operations(cls):
+        return cls.one_to_many_relationship('operation', key_column_name='name')
+
+    @declared_attr
+    def interface_template(cls):
+        return cls.many_to_one_relationship('interface_template')
+
+    # region foreign_keys
+
+    # Node one-to-many to Interface
+    @declared_attr
+    def node_fk(cls):
+        return cls.foreign_key('node', nullable=True)
+
+    # Group one-to-many to Interface
+    @declared_attr
+    def group_fk(cls):
+        return cls.foreign_key('group', nullable=True)
+
+    # Relationship one-to-many to Interface
+    @declared_attr
+    def relationship_fk(cls):
+        return cls.foreign_key('relationship', nullable=True)
+
+    # Interface many-to-one to InterfaceTemplate
+    @declared_attr
+    def interface_template_fk(cls):
+        return cls.foreign_key('interface_template')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('description', self.description),
+            ('type_name', self.type_name),
+            ('inputs', formatting.as_raw_dict(self.inputs)),
+            ('operations', formatting.as_raw_list(self.operations))))
+
+    def validate(self, context):
+        if self.type_name:
+            if context.modeling.interface_types.get_descendant(self.type_name) is None:
+                context.validation.report('interface "{0}" has an unknown type: {1}'.format(
+                                            self.name,
+                                            formatting.safe_repr(self.type_name)),
+                                          level=validation.Issue.BETWEEN_TYPES)
+
+        utils.validate_dict_values(context, self.inputs)
+        utils.validate_dict_values(context, self.operations)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.inputs, report_issues)
+        utils.coerce_dict_values(context, container, self.operations, report_issues)
+
+    def dump(self, context):
+        console.puts(context.style.node(self.name))
+        if self.description:
+            console.puts(context.style.meta(self.description))
+        with context.style.indent:
+            console.puts('Interface type: {0}'.format(context.style.type(self.type_name)))
+            utils.dump_parameters(context, self.inputs, 'Inputs')
+            utils.dump_dict_values(context, self.operations, 'Operations')
+
+
+class OperationBase(_InstanceModelMixin):
+    """
+    An operation in a :class:`Interface`.
+
+    :ivar name: Name
+    :ivar description: Description
+    :ivar implementation: Implementation string (interpreted by the orchestrator)
+    :ivar dependencies: List of strings (interpreted by the orchestrator)
+    :ivar executor: Executor string (interpreted by the orchestrator)
+    :ivar max_retries: Maximum number of retries allowed in case of failure
+    :ivar retry_interval: Interval between retries
+    :ivar inputs: Dict of :class:`Parameter`
+    """
+
+    __tablename__ = 'operation' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['service_fk',
+                          'interface_fk',
+                          'plugin_fk',
+                          'operation_template_fk']
+
+    description = Column(Text)
+    implementation = Column(Text)
+    dependencies = Column(modeling_types.StrictList(item_cls=basestring))
+    executor = Column(Text)
+    max_retries = Column(Integer)
+    retry_interval = Column(Integer)
+
+    @declared_attr
+    def inputs(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='inputs',
+                                             key_column_name='name')
+
+    @declared_attr
+    def plugin(cls):
+        return cls.one_to_one_relationship('plugin')
+
+    @declared_attr
+    def operation_template(cls):
+        return cls.many_to_one_relationship('operation_template')
+
+    # region foreign_keys
+
+    # Service one-to-many to Operation
+    @declared_attr
+    def service_fk(cls):
+        return cls.foreign_key('service', nullable=True)
+
+    # Interface one-to-many to Operation
+    @declared_attr
+    def interface_fk(cls):
+        return cls.foreign_key('interface', nullable=True)
+
+    # Operation one-to-one to Plugin
+    @declared_attr
+    def plugin_fk(cls):
+        return cls.foreign_key('plugin', nullable=True)
+
+    # Operation many-to-one to OperationTemplate
+    @declared_attr
+    def operation_template_fk(cls):
+        return cls.foreign_key('operation_template')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('description', self.description),
+            ('implementation', self.implementation),
+            ('dependencies', self.dependencies),
+            ('executor', self.executor),
+            ('max_retries', self.max_retries),
+            ('retry_interval', self.retry_interval),
+            ('inputs', formatting.as_raw_dict(self.inputs))))
+
+    def validate(self, context):
+        utils.validate_dict_values(context, self.inputs)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.inputs, report_issues)
+
+    def dump(self, context):
+        console.puts(context.style.node(self.name))
+        if self.description:
+            console.puts(context.style.meta(self.description))
+        with context.style.indent:
+            if self.implementation is not None:
+                console.puts('Implementation: {0}'.format(
+                    context.style.literal(self.implementation)))
+            if self.dependencies:
+                console.puts(
+                    'Dependencies: {0}'.format(
+                        ', '.join((str(context.style.literal(v)) for v in self.dependencies))))
+            if self.executor is not None:
+                console.puts('Executor: {0}'.format(context.style.literal(self.executor)))
+            if self.max_retries is not None:
+                console.puts('Max retries: {0}'.format(context.style.literal(self.max_retries)))
+            if self.retry_interval is not None:
+                console.puts('Retry interval: {0}'.format(
+                    context.style.literal(self.retry_interval)))
+            utils.dump_parameters(context, self.inputs, 'Inputs')
+
+
+class ArtifactBase(_InstanceModelMixin):
+    """
+    A file associated with a :class:`Node`.
+
+    :ivar name: Name
+    :ivar description: Description
+    :ivar type_name: Must be represented in the :class:`ModelingContext`
+    :ivar source_path: Source path (CSAR or repository)
+    :ivar target_path: Path at destination machine
+    :ivar repository_url: Repository URL
+    :ivar repository_credential: Dict of string
+    :ivar properties: Dict of :class:`Parameter`
+    """
+
+    __tablename__ = 'artifact' # redundancy for PyLint: SqlAlchemy injects this
+
+    __private_fields__ = ['node_fk',
+                          'artifact_template_fk']
+
+    description = Column(Text)
+    type_name = Column(Text)
+    source_path = Column(Text)
+    target_path = Column(Text)
+    repository_url = Column(Text)
+    repository_credential = Column(modeling_types.StrictDict(basestring, basestring))
+
+    @declared_attr
+    def properties(cls):
+        return cls.many_to_many_relationship('parameter', table_prefix='properties',
+                                             key_column_name='name')
+
+    @declared_attr
+    def artifact_template(cls):
+        return cls.many_to_one_relationship('artifact_template')
+
+    # region foreign_keys
+
+    # Node one-to-many to Artifact
+    @declared_attr
+    def node_fk(cls):
+        return cls.foreign_key('node')
+
+    # Artifact many-to-one to ArtifactTemplate
+    @declared_attr
+    def artifact_template_fk(cls):
+        return cls.foreign_key('artifact_template')
+
+    # endregion
+
+    @property
+    def as_raw(self):
+        return collections.OrderedDict((
+            ('name', self.name),
+            ('description', self.description),
+            ('type_name', self.type_name),
+            ('source_path', self.source_path),
+            ('target_path', self.target_path),
+            ('repository_url', self.repository_url),
+            ('repository_credential', formatting.as_agnostic(self.repository_credential)),
+            ('properties', formatting.as_raw_dict(self.properties))))
+
+    def validate(self, context):
+        if context.modeling.artifact_types.get_descendant(self.type_name) is None:
+            context.validation.report('artifact "{0}" has an unknown type: {1}'.format(
+                                        self.name,
+                                        formatting.safe_repr(self.type_name)),
+                                      level=validation.Issue.BETWEEN_TYPES)
+        utils.validate_dict_values(context, self.properties)
+
+    def coerce_values(self, context, container, report_issues):
+        utils.coerce_dict_values(context, container, self.properties, report_issues)
+
+    def dump(self, context):
+        console.puts(context.style.node(self.name))
+        if self.description:
+            console.puts(context.style.meta(self.description))
+        with context.style.indent:
+            console.puts('Artifact type: {0}'.format(context.style.type(self.type_name)))
+            console.puts('Source path: {0}'.format(context.style.literal(self.source_path)))
+            if self.target_path is not None:
+                console.puts('Target path: {0}'.format(context.style.literal(self.target_path)))
+            if self.repository_url is not None:
+                console.puts('Repository URL: {0}'.format(
+                    context.style.literal(self.repository_url)))
+            if self.repository_credential:
+                console.puts('Repository credential: {0}'.format(
+                    context.style.literal(self.repository_credential)))
+            utils.dump_parameters(context, self.properties)