We have some ROS graph information available through our C++ and Python API’s:
- http://docs.ros2.org/ardent/api/rclcpp/index.html (search for “introspecting the ROS graph”)
- https://github.com/ros2/rclpy/blob/5b219126664ee4bed352aa9ebd15e92d93d0f69c/rclpy/rclpy/node.py#L290-L297 (sorry no docs for these yet)