ros2 / ros2/ros2cli

Ros2 node info does not show info for nodes of the same name

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Dominant language
Python
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Forks
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Merged PRs (30d)
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Description

It is possible to launch multiple nodes of the same name. When this happens, those multiple nodes show up in ros2 node list but it is impossible to get info on these nodes with ros2 node info.

In the below example, I have launched a single amcl process which spins up 3 nodes. But since the three nodes were assigned the same name, I can't introspect to see what topics those nodes are listening/publishing on.

$ ros2 node list
/KeystrokeListen
/launch_ros
/launch_ros
/launch_ros
/rover_serial
/ArrowsToTwist
/se_node
/bno055_driver
/rviz
/robot_state_publisher
/joint_state_publisher
/amcl
/rplidar_node
/amcl
/rover
/se_node/transform_listener_impl/transform_listener_impl
/amcl

$ ros2 node info /amcl
/amcl
  Subscribers:
    /parameter_events: rcl_interfaces/msg/ParameterEvent
  Publishers:
    /amcl/transition_event: lifecycle_msgs/msg/TransitionEvent
    /parameter_events: rcl_interfaces/msg/ParameterEvent
    /rosout: rcl_interfaces/msg/Log
  Services:
    /amcl/change_state: lifecycle_msgs/srv/ChangeState
    /amcl/describe_parameters: rcl_interfaces/srv/DescribeParameters
    /amcl/get_available_states: lifecycle_msgs/srv/GetAvailableStates
    /amcl/get_available_transitions: lifecycle_msgs/srv/GetAvailableTransitions
    /amcl/get_parameter_types: rcl_interfaces/srv/GetParameterTypes
    /amcl/get_parameters: rcl_interfaces/srv/GetParameters
    /amcl/get_state: lifecycle_msgs/srv/GetState
    /amcl/get_transition_graph: lifecycle_msgs/srv/GetAvailableTransitions
    /amcl/list_parameters: rcl_interfaces/srv/ListParameters
    /amcl/set_parameters: rcl_interfaces/srv/SetParameters
    /amcl/set_parameters_atomically: rcl_interfaces/srv/SetParametersAtomically

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the duplicate-name case with ros2 node list and ros2 node info /amcl, using the commands and output in the issue. Trace the ros2 node info entry point and determine how it can select among same-named nodes; done means each duplicate node can be introspected distinctly.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
cli
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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