Namespace doesn't get applied to target container when using load_composable_node tag

[mbharatheesha]

So, I have an xml launch (let's say: pkg.launch.xml) from binaries as follows:

<launch>
    <arg name="some_arg" default="true"/>
   
    <node pkg="rclcpp_components" exec="component_container" name="container" >
    </node>
    <load_composable_node if="$(var some_arg)" target="container">
        <composable_node  pkg="pkg" plugin="pkg::SomePlugin" name="c_node" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>   

    <load_composable_node unless="$(var some_arg)" target="container">
        <composable_node  pkg="pkg" plugin="pkg::SomeOtherPlugin" name="c_node" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>
  
    <load_composable_node target="container">
        <composable_node  pkg="pkg" plugin="pkg::Plugin" name="c_node1" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>
</launch>

And, I have a top level launch file top_level.launch.xml as follows:

<launch>
    <arg name="my_arg" default="my_default" />

    <group>
    <push_ros_namespace namespace="$(var my_arg)" />
        <include file="$(find-pkg-share pkg)/launch/pkg.launch.xml" >
            <arg name="some_arg" value="false" />
        </include>
    </group>
</launch>

• Operating System:
  • ubuntu 24.04 LTS
• Installation type:
  • ROS2 Jazzy from binaries
• DDS implementation:
  • CycloneDDS

Steps to reproduce issue

ros2 launch top_level.launch.xml

Expected behavior

I expect that all composable nodes should get loaded into my_default/container

Actual behavior

The composable nodes seem to be looking for container instead

Additional information

The only way to get the composable nodes loaded into the namespaced container is to accept the namespace string as a launch argument and append it to the target tag, like so:

<?xml version="1.0"?>
<launch>
    <arg name="some_arg" default="true"/>
    <arg namespace="namespace" default="my_ns"/>

   
    <node pkg="rclcpp_components" exec="component_container" name="container" >
    </node>
    <load_composable_node if="$(var some_arg)" target="$(var namespace)/container">
        <composable_node  pkg="pkg" plugin="pkg::SomePlugin" name="c_node" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>   

    <load_composable_node unless="$(var some_arg)" target="$(var namespace)/container">
        <composable_node  pkg="pkg" plugin="pkg::SomeOtherPlugin" name="c_node" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>
  
    <load_composable_node target="$(var namespace)/container">
        <composable_node  pkg="pkg" plugin="pkg::Plugin" name="c_node1" namespace="">
            <param name="param" value="value" />
        </composable_node>
    </load_composable_node>
</launch>

And modify, the top_level.launch.xml like so:

<launch>
    <arg name="my_arg" default="my_default" />

    <group>
    <push_ros_namespace namespace="$(var my_arg)" />
        <include file="$(find-pkg-share pkg)/launch/pkg.launch.xml" >
            <arg name="some_arg" value="false" />
            <arg namespace="$(var namespace)" />
        </include>
    </group>
</launch>

But, this would only work, if the binary installed xml launch file has already considered the option to append namespaces to target container names.

---

Feature request

Enable the target containers in load_composable_node tags to acquire the namespace from the push_ros_namespace tag, if one is specified.

Note:

I am not sure if this is a bug or if there's a different way the <load_composable_node> tag is to be used when using namespaces.

[sloretz]

I am not sure if this is a bug

Seems like a bug 🧇

[mbharatheesha]

I am not sure if this is a bug

Seems like a bug 🧇

@sloretz
Alright.
I took a stab at it with #429 . And it seems to introduce the expected behavior. If you have any suggestions on doing it differently, I look forward to hearing the same and help out if I can.