refactor: remove Model from hydration where possible

Author: yt-ms

src/structurizr/mixin/model_ref_mixin.py

@@ -20,7 +20,7 @@
 from weakref import ref
 
 
-if TYPE_CHECKING:
+if TYPE_CHECKING:  # pragma: no cover
     from ..model import Model
 
 
@@ -40,6 +40,11 @@ def model(self) -> "Model":
         """Return the referenced model."""
         return self.get_model()
 
+    @property
+    def is_in_model(self) -> bool:
+        """Return whether a model has been set."""
+        return self._model() is not None
+
     def get_model(self) -> "Model":
         """
         Retrieve the model instance from the reference.

src/structurizr/model/component.py

@@ -27,7 +27,6 @@
 
 if TYPE_CHECKING:  # pragma: no cover
     from .container import Container
-    from .model import Model
 
 
 __all__ = ("Component", "ComponentIO")
@@ -109,9 +108,7 @@ def __init__(
         self.tags.add(Tags.COMPONENT)
 
     @classmethod
-    def hydrate(
-        cls, component_io: ComponentIO, container: "Container", model: "Model"
-    ) -> "Component":
+    def hydrate(cls, component_io: ComponentIO, container: "Container") -> "Component":
         """Create and hydrate a new `Component` instance from its IO.
 
         This will also automatically register with the model.
@@ -123,5 +120,4 @@ def hydrate(
             # TODO: code_elements=map(CodeElement.hydrate, component_io.components),
             size=component_io.size,
         )
-        model += component
         return component

src/structurizr/model/container.py

@@ -25,7 +25,6 @@
 
 
 if TYPE_CHECKING:  # pragma: no cover
-    from .model import Model
     from .software_system import SoftwareSystem
 
 
@@ -117,23 +116,16 @@ def hydrate(
         cls,
         container_io: ContainerIO,
         software_system: "SoftwareSystem",
-        model: "Model",
     ) -> "Container":
-        """Hydrate a new Container instance from its IO.
-
-        This will also automatically register with the model.
-        """
+        """Hydrate a new Container instance from its IO."""
         container = cls(
             **cls.hydrate_arguments(container_io),
             parent=software_system,
             technology=container_io.technology,
         )
-        model += container
 
         for component_io in container_io.components:
-            component = Component.hydrate(
-                component_io, container=container, model=model
-            )
+            component = Component.hydrate(component_io, container=container)
             container += component
 
         return container
@@ -164,8 +156,9 @@ def __iadd__(self, component: Component) -> "Container":
                 f"{component.parent}. Cannot add to {self}."
             )
         self._components.add(component)
-        model = self.model
-        model += component
+        if self.is_in_model:
+            model = self.model
+            model += component
         return self
 
     def get_component_with_name(self, name: str) -> Component:

src/structurizr/model/deployment_node.py

@@ -280,8 +280,9 @@ def _add_child_deployment_node(self, node: "DeploymentNode"):
                 f"{node.parent}. Cannot add to {self}."
             )
         self._children.add(node)
-        model = self.model
-        model += node
+        if self.is_in_model:
+            model = self.model
+            model += node
 
     @classmethod
     def hydrate(
@@ -290,15 +291,11 @@ def hydrate(
         model: "Model",
         parent: "DeploymentNode" = None,
     ) -> "DeploymentNode":
-        """Hydrate a new DeploymentNode instance from its IO.
-
-        This will also automatically register with the model.
-        """
+        """Hydrate a new DeploymentNode instance from its IO."""
         node = cls(
             **cls.hydrate_arguments(deployment_node_io),
             parent=parent,
         )
-        model += node
 
         for child_io in deployment_node_io.children:
             child_node = DeploymentNode.hydrate(child_io, model=model, parent=node)
@@ -315,9 +312,7 @@ def hydrate(
             node._software_system_instances.add(instance)
 
         for infra_node_io in deployment_node_io.infrastructure_nodes:
-            infra_node = InfrastructureNode.hydrate(
-                infra_node_io, model=model, parent=node
-            )
+            infra_node = InfrastructureNode.hydrate(infra_node_io, parent=node)
             node._infrastructure_nodes.add(infra_node)
 
         return node

src/structurizr/model/infrastructure_node.py

@@ -21,7 +21,6 @@
 
 if TYPE_CHECKING:  # pragma: no cover
     from .deployment_node import DeploymentNode
-    from .model import Model
 
 
 __all__ = ("InfrastructureNode", "InfrastructureNodeIO")
@@ -69,17 +68,12 @@ def __init__(
     def hydrate(
         cls,
         node_io: InfrastructureNodeIO,
-        model: "Model",
         parent: "DeploymentNode",
     ) -> "InfrastructureNode":
-        """Hydrate a new InfrastructureNode instance from its IO.
-
-        This will also automatically register with the model.
-        """
+        """Hydrate a new InfrastructureNode instance from its IO."""
         node = cls(
             **cls.hydrate_arguments(node_io),
             technology=node_io.technology,
             parent=parent,
         )
-        model += node
         return node

src/structurizr/model/model.py

@@ -153,13 +153,13 @@ def hydrate(cls, model_io: ModelIO) -> "Model":
         )
 
         for person_io in model_io.people:
-            Person.hydrate(person_io, model=model)
+            model += Person.hydrate(person_io)
 
         for software_system_io in model_io.software_systems:
-            SoftwareSystem.hydrate(software_system_io, model=model)
+            model += SoftwareSystem.hydrate(software_system_io)
 
         for deployment_node_io in model_io.deployment_nodes:
-            DeploymentNode.hydrate(deployment_node_io, model=model)
+            model += DeploymentNode.hydrate(deployment_node_io, model=model)
 
         for element in model.get_elements():
             for relationship in element.relationships:
@@ -368,6 +368,8 @@ def _add_element(self, element: Element) -> None:
         self._elements_by_id[element.id] = element
         element.set_model(self)
         self._id_generator.found(element.id)
+        for child in element.child_elements:
+            self += child
 
     def _add_relationship(
         self, relationship: Relationship, create_implied_relationships: bool

src/structurizr/model/person.py

@@ -16,7 +16,7 @@
 """Provide a person model."""
 
 
-from typing import TYPE_CHECKING, Optional
+from typing import Optional
 
 from pydantic import Field
 
@@ -26,9 +26,6 @@
 from .tags import Tags
 
 
-if TYPE_CHECKING:  # pragma: no cover
-    from .model import Model
-
 __all__ = ("PersonIO", "Person")
 
 
@@ -63,16 +60,12 @@ def __init__(self, *, location: Location = Location.Unspecified, **kwargs) -> No
         self.tags.add(Tags.PERSON)
 
     @classmethod
-    def hydrate(cls, person_io: PersonIO, model: "Model") -> "Person":
-        """Create a new person and hydrate from its IO.
-
-        This will also automatically register with the model.
-        """
+    def hydrate(cls, person_io: PersonIO) -> "Person":
+        """Create a new person and hydrate from its IO."""
         person = cls(
             **cls.hydrate_arguments(person_io),
             location=person_io.location,
         )
-        model += person
         return person
 
     def interacts_with(

src/structurizr/model/software_system.py

@@ -16,7 +16,7 @@
 """Provide a software system element model."""
 
 
-from typing import TYPE_CHECKING, Iterable, List, Set
+from typing import Iterable, List, Set
 
 from pydantic import Field
 
@@ -26,10 +26,6 @@
 from .tags import Tags
 
 
-if TYPE_CHECKING:  # pragma: no cover
-    from .model import Model
-
-
 __all__ = ("SoftwareSystem", "SoftwareSystemIO")
 
 
@@ -114,33 +110,27 @@ def __iadd__(self, container: Container) -> "SoftwareSystem":
                 f"{container.parent}. Cannot add to {self}."
             )
         self._containers.add(container)
-        model = self.model
-        model += container
+        if self.is_in_model:
+            model = self.model
+            model += container
         return self
 
     def get_container_with_name(self, name: str) -> Container:
         """Return the container with the given name, or None."""
         return next((c for c in self._containers if c.name == name), None)
 
     @classmethod
-    def hydrate(
-        cls, software_system_io: SoftwareSystemIO, model: "Model"
-    ) -> "SoftwareSystem":
-        """Create a new SoftwareSystem instance and hydrate it from its IO.
-
-        This will also automatically register with the model.
-        """
+    def hydrate(cls, software_system_io: SoftwareSystemIO) -> "SoftwareSystem":
+        """Create a new SoftwareSystem instance and hydrate it from its IO."""
         software_system = cls(
             **cls.hydrate_arguments(software_system_io),
             location=software_system_io.location,
         )
-        model += software_system
 
         for container_io in software_system_io.containers:
             software_system += Container.hydrate(
                 container_io,
                 software_system=software_system,
-                model=model,
             )
 
         return software_system

src/structurizr/model/software_system_instance.py

@@ -67,15 +67,11 @@ def hydrate(
         model: "Model",
         parent: "DeploymentNode",
     ) -> "SoftwareSystemInstance":
-        """Hydrate a new SoftwareSystemInstance instance from its IO.
-
-        This will also automatically register with the model.
-        """
+        """Hydrate a new SoftwareSystemInstance instance from its IO."""
         system = model.get_element(system_instance_io.software_system_id)
         instance = cls(
             **cls.hydrate_arguments(system_instance_io),
             software_system=system,
             parent=parent,
         )
-        model += instance
         return instance

tests/unit/model/test_deployment_node.py

@@ -128,7 +128,6 @@ def test_deployment_node_serialization_of_recursive_nodes(model_with_node):
     new_child = new_top_node.children[0]
     assert new_child.name == "child"
     assert new_child.parent is new_top_node
-    assert new_child.model is model_with_node
 
 
 def test_deployment_node_add_container(model_with_node):
@@ -190,7 +189,6 @@ def test_deployment_node_serialising_container(model_with_node):
     instance = node2.container_instances[0]
     assert instance.instance_id == 1
     assert instance.container is container
-    assert instance.model is model_with_node
     assert instance.parent is node2
 
 
@@ -226,7 +224,6 @@ def test_deployment_node_serialising_software_system(model_with_node):
     instance = node2.software_system_instances[0]
     assert instance.instance_id == 1
     assert instance.software_system is system
-    assert instance.model is model_with_node
     assert instance.parent is node2
 
 
@@ -258,5 +255,4 @@ def test_deployment_node_serialising_infrastructure_nodes(model_with_node):
     assert len(node2.infrastructure_nodes) == 1
     infra_node = node2.infrastructure_nodes[0]
     assert infra_node.name == "infraNode"
-    assert infra_node.model is model_with_node
     assert infra_node.parent is node2