add utility to import complex message and add support for nested arra…

…y in set_message

Signed-off-by: Mikael Arguedas <[email protected]>

rosidl_runtime_py/rosidl_runtime_py/import_message.py

@@ -0,0 +1,24 @@
+# Copyright 2019 Mikael Arguedas.
+#
+# Licensed 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 importlib
+from typing import Any
+
+from rosidl_parser.definition import NamespacedType
+
+
+def import_message_from_namespaced_type(message_type: NamespacedType) -> Any:
+    module = importlib.import_module(
+            '.'.join(message_type.basetype.namespaces))
+    return getattr(module, message_type.basetype.name)

rosidl_runtime_py/rosidl_runtime_py/set_message.py

@@ -15,6 +15,10 @@
 from typing import Any
 from typing import Dict
 
+from rosidl_parser.definition import NamespacedType
+from rosidl_runtime_py.convert import slot_types_dict_from_message
+from rosidl_runtime_py.import_message import import_message_from_namespaced_type
+
 
 def set_message_fields(msg: Any, values: Dict[str, str]) -> None:
     """
@@ -33,4 +37,13 @@ def set_message_fields(msg: Any, values: Dict[str, str]) -> None:
         except TypeError:
             value = field_type()
             set_message_fields(value, field_value)
+        rosidl_type = slot_types_dict_from_message(msg)[field_name]
+        # Check if field is an array of ROS messages
+        if isinstance(field_type(), list):
+            if isinstance(rosidl_type.basetype, NamespacedType):
+                field_elem_type = import_message_from_namespaced_type(rosidl_type)
+                for n in range(len(value)):
+                    submsg = field_elem_type()
+                    set_message_fields(submsg, value[n])
+                    value[n] = submsg
         setattr(msg, field_name, value)