Derive Messages from Base Classes (#230)

Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
Co-authored-by: Christophe Bedard <bedard.christophe@gmail.com>

Author: InvincibleRMC

rosidl_generator_py/resource/_action.py.em

@@ -42,7 +42,7 @@ TEMPLATE(
 }@
 
 
-class Metaclass_@(action.namespaced_type.name)(type):
+class Metaclass_@(action.namespaced_type.name)(rosidl_pycommon.interface_base_classes.ActionTypeSupportMeta):
     """Metaclass of action '@(action.namespaced_type.name)'."""
 
     _TYPE_SUPPORT: typing.ClassVar[typing.Optional[PyCapsule]] = None
@@ -79,14 +79,18 @@ class Metaclass_@(action.namespaced_type.name)(type):
                 @(module_name).Metaclass_@(action.feedback_message.structure.namespaced_type.name).__import_type_support__()
 
 
-class @(action.namespaced_type.name)(metaclass=Metaclass_@(action.namespaced_type.name)):
+class @(action.namespaced_type.name)(rosidl_pycommon.interface_base_classes.BaseAction[
+    @(action.goal.structure.namespaced_type.name),
+    @(action.result.structure.namespaced_type.name),
+    @(action.feedback.structure.namespaced_type.name)
+], metaclass=Metaclass_@(action.namespaced_type.name)):
 
     # The goal message defined in the action definition.
-    from @('.'.join(action.namespaced_type.namespaces)).@(module_name) import @(action.goal.structure.namespaced_type.name) as Goal
+    Goal: type[@(action.goal.structure.namespaced_type.name)] = @(action.goal.structure.namespaced_type.name)
     # The result message defined in the action definition.
-    from @('.'.join(action.namespaced_type.namespaces)).@(module_name) import @(action.result.structure.namespaced_type.name) as Result
+    Result: type[@(action.result.structure.namespaced_type.name)] = @(action.result.structure.namespaced_type.name)
     # The feedback message defined in the action definition.
-    from @('.'.join(action.namespaced_type.namespaces)).@(module_name) import @(action.feedback.structure.namespaced_type.name) as Feedback
+    Feedback: type[@(action.feedback.structure.namespaced_type.name)] = @(action.feedback.structure.namespaced_type.name)
 
     class Impl:
 

rosidl_generator_py/resource/_idl.py.em

@@ -8,6 +8,8 @@ import collections.abc
 from os import getenv
 import typing
 
+import rosidl_pycommon.interface_base_classes
+
 # This is being done at the module level and not on the instance level to avoid looking
 # for the same variable multiple times on each instance. This variable is not supposed to
 # change during runtime so it makes sense to only look for it once.

rosidl_generator_py/resource/_msg.py.em

@@ -138,7 +138,7 @@ for member in message.structure.members:
 @#>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
 
 
-class Metaclass_@(message.structure.namespaced_type.name)(type):
+class Metaclass_@(message.structure.namespaced_type.name)(rosidl_pycommon.interface_base_classes.MessageTypeSupportMeta):
     """Metaclass of message '@(message.structure.namespaced_type.name)'."""
 
     _CREATE_ROS_MESSAGE: typing.ClassVar[typing.Optional[PyCapsule]] = None
@@ -244,7 +244,7 @@ for member in message.structure.members:
 @[end for]@
 
 
-class @(message.structure.namespaced_type.name)(metaclass=Metaclass_@(message.structure.namespaced_type.name)):
+class @(message.structure.namespaced_type.name)(rosidl_pycommon.interface_base_classes.BaseMessage, metaclass=Metaclass_@(message.structure.namespaced_type.name)):
 @[if not message.constants]@
     """Message class '@(message.structure.namespaced_type.name)'."""
 @[else]@

rosidl_generator_py/resource/_srv.py.em

@@ -26,7 +26,7 @@ TEMPLATE(
 }@
 
 
-class Metaclass_@(service.namespaced_type.name)(type):
+class Metaclass_@(service.namespaced_type.name)(rosidl_pycommon.interface_base_classes.ServiceTypeSupportMeta):
     """Metaclass of service '@(service.namespaced_type.name)'."""
 
     _TYPE_SUPPORT: typing.ClassVar[typing.Optional[PyCapsule]] = None
@@ -56,9 +56,12 @@ class Metaclass_@(service.namespaced_type.name)(type):
                 @(module_name).Metaclass_@(service.event_message.structure.namespaced_type.name).__import_type_support__()
 
 
-class @(service.namespaced_type.name)(metaclass=Metaclass_@(service.namespaced_type.name)):
-    from @('.'.join(service.namespaced_type.namespaces)).@(module_name) import @(service.request_message.structure.namespaced_type.name) as Request
-    from @('.'.join(service.namespaced_type.namespaces)).@(module_name) import @(service.response_message.structure.namespaced_type.name) as Response
+class @(service.namespaced_type.name)(rosidl_pycommon.interface_base_classes.BaseService[
+    @(service.request_message.structure.namespaced_type.name),
+    @(service.response_message.structure.namespaced_type.name)
+], metaclass=Metaclass_@(service.namespaced_type.name)):
+    Request: type[@(service.request_message.structure.namespaced_type.name)] = @(service.request_message.structure.namespaced_type.name)
+    Response: type[@(service.response_message.structure.namespaced_type.name)] = @(service.response_message.structure.namespaced_type.name)
     from @('.'.join(service.namespaced_type.namespaces)).@(module_name) import @(service.event_message.structure.namespaced_type.name) as Event
 
     # Should eventually be typing.NoReturn. See mypy#14044