Deduplicate scope node checks (#97)

Signed-off-by: Michel Hidalgo <[email protected]>

bdai_ros2_wrappers/bdai_ros2_wrappers/action.py

@@ -358,7 +358,8 @@ def __init__(self, action_type: Type, action_name: str, node: Optional[Node] = N
             kwargs: other keyword arguments are forwarded to the underlying action client.
             See `rclpy.action.ActionClient` documentation for further reference.
         """
-        node = node or scope.node()
+        if node is None:
+            node = scope.ensure_node()
         self._action_type = action_type
         self._action_name = action_name
         self._action_client = ActionClient(node, action_type, action_name, **kwargs)

bdai_ros2_wrappers/bdai_ros2_wrappers/action_client.py

@@ -27,9 +27,8 @@ def __init__(
             node (Optional[Node]): optional node for action client, defaults to the current process node
             wait_for_server (bool): Whether to wait for the server
         """
-        node = node or scope.node()
         if node is None:
-            raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+            node = scope.ensure_node()
         self._node = node
         super().__init__(self._node, action_type, action_name)
         if wait_for_server:

bdai_ros2_wrappers/bdai_ros2_wrappers/scope.py

@@ -529,6 +529,14 @@ def node() -> typing.Optional[rclpy.node.Node]:
     return scope.node
 
 
+def ensure_node() -> rclpy.node.Node:
+    """Gets a node from the current ROS 2 aware scope or fails trying"""
+    current_node = node()
+    if current_node is None:
+        raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+    return current_node
+
+
 def tf_listener() -> typing.Optional[TFListenerWrapper]:
     """Gets the tf listener of the current ROS 2 aware scope, if any."""
     scope = current()

bdai_ros2_wrappers/bdai_ros2_wrappers/service.py

@@ -40,9 +40,8 @@ class Serviced(ComposableCallable, VectorizingCallable):
     """
 
     def __init__(self, service_type: Type, service_name: str, node: Optional[Node] = None, **kwargs: Any) -> None:
-        node = node or scope.node()
         if node is None:
-            raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+            node = scope.ensure_node()
         self._service_type = service_type
         self._service_name = service_name
         self._client = node.create_client(service_type, service_name, **kwargs)

bdai_ros2_wrappers/bdai_ros2_wrappers/subscription.py

@@ -45,9 +45,8 @@ def __init__(
             kwargs: other keyword arguments are used to create the underlying native subscription.
             See `rclpy.node.Node.create_subscription` documentation for further reference.
         """
-        node = node or scope.node()
         if node is None:
-            raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+            node = scope.ensure_node()
         self._node = node
         if history_length is None:
             history_length = 1
@@ -150,9 +149,8 @@ def wait_for_message_async(
     Raises:
         RuntimeError: if no node is available.
     """
-    node = node or scope.node()
     if node is None:
-        raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+        node = scope.ensure_node()
     future = Future()
 
     def callback(msg: MessageT) -> None:
@@ -187,9 +185,8 @@ def wait_for_message(
     Returns:
         The message received, or None on timeout.
     """
-    node = node or scope.node()
     if node is None:
-        raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+        node = scope.ensure_node()
     future = wait_for_message_async(msg_type, topic_name, node=node, **kwargs)
     if not wait_for_future(future, timeout_sec, context=node.context):
         future.cancel()
@@ -224,9 +221,8 @@ def wait_for_messages(
     See `wait_for_messages_async` documentation for a reference on
     additional keyword arguments.
     """
-    node = node or scope.node()
     if node is None:
-        raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+        node = scope.ensure_node()
     future = wait_for_messages_async(topic_names, message_types, node=node, **kwargs)
     if not wait_for_future(future, timeout_sec, context=node.context):
         future.cancel()
@@ -261,9 +257,8 @@ def wait_for_messages_async(
         process-wide node (if any).
         callback_group: optional callback group for the message filter subscribers.
     """
-    node = node or scope.node()
     if node is None:
-        raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+        node = scope.ensure_node()
 
     if qos_profiles is None:
         qos_profiles = [None] * len(topic_names)

bdai_ros2_wrappers/bdai_ros2_wrappers/tf_listener_wrapper.py

@@ -71,11 +71,10 @@ def __init__(self, node: Optional[Node] = None, cache_time_s: Optional[float] =
             node: optional node for transform listening, defaults to the current scope node.
             cache_time_s: optional transform buffer size, in seconds.
         """
-        import bdai_ros2_wrappers.scope  # locally to avoid circular import
+        import bdai_ros2_wrappers.scope as scope  # locally to avoid circular import
 
-        node = node or bdai_ros2_wrappers.scope.node()
         if node is None:
-            raise ValueError("no ROS 2 node available (did you use bdai_ros2_wrapper.process.main?)")
+            node = scope.ensure_node()
         self._node = node
         cache_time_py = None
         if cache_time_s is not None: