More ROS1-like tab-completion for ros2topic / ros2service

[peci1]

Description

In ROS 1, bash completion after rostopic pub /topic suggested the topic type, and after rostopic pub /topic type suggested the message template.

I think this behavior was very convenient. Even though the command has more parameters that could be added.

I don't know if it's possible implementation-wise, but it'd be great to pretend for autocompletion that topic name can only be followed by type and topic type can only be followed by message prototype.

Motivation

Make ros2 CLI more user-friendly.

Design / Implementation Considerations

I know there was recently some motion with fzf, but I haven't tried myself yet, so I can't comment on whether it solves this request or not.

Additional Information

No response

[fujitatomoya]

@peci1

ros2 topic pub seems to show the type and message template as below.

root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test nav_msgs/msg/
nav_msgs/msg/Goals            nav_msgs/msg/MapMetaData      nav_msgs/msg/Odometry         nav_msgs/msg/Trajectory       
nav_msgs/msg/GridCells        nav_msgs/msg/OccupancyGrid    nav_msgs/msg/Path             nav_msgs/msg/TrajectoryPoint  
root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test nav_msgs/msg/
nav_msgs/msg/Goals            nav_msgs/msg/MapMetaData      nav_msgs/msg/Odometry         nav_msgs/msg/Trajectory       
nav_msgs/msg/GridCells        nav_msgs/msg/OccupancyGrid    nav_msgs/msg/Path             nav_msgs/msg/TrajectoryPoint  
root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test nav_msgs/msg/Trajectory 'header:
  stamp:
    sec: 0
    nanosec: 0
  frame_id: ''
points: []
' 
publisher: beginning loop
publishing #1: nav_msgs.msg.Trajectory(header=std_msgs.msg.Header(stamp=builtin_interfaces.msg.Time(sec=0, nanosec=0), frame_id='None'), points=[])

publishing #2: nav_msgs.msg.Trajectory(header=std_msgs.msg.Header(stamp=builtin_interfaces.msg.Time(sec=0, nanosec=0), frame_id='None'), points=[])
...

on the other hand, unfortunately ros2 service call does not seem to work like ros2 topic pub...

[peci1]

When exactly did you press Tab in the last example? In my experience (Kilted) you have to first type\' to get the completion.

Also, what you show is completion of a half-typed message type. That's okay. What I ask for in this issue is completion on not-yet typed parts of the command. Like ros2 topic pub /test <Tab>.

[ros-discourse]

This issue has been mentioned on Open Robotics Discourse. There might be relevant details there:

https://discourse.openrobotics.org/t/ros-news-for-the-week-of-february-23rd-2026/52787/1

[tonynajjar]

@fujitatomoya @peci1 if you can confirm that #1151 introduced a bug by comparing before and after please let me know and I'll be happy to fix it

[fujitatomoya]

@peci1

with e7bb62e (today's head),

• can list the all message types as suggestion.

root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test <tab><tab>
Display all 229 possibilities? (y or n)

• after the message type, it can also complete the default values to be published.

root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test builtin_interfaces/msg/Time <tab><tab> 
root@tomoyafujita-B760M-Pro-RS-D4:~/ros2_ws/colcon_ws# ros2 topic pub /test builtin_interfaces/msg/Time 'sec: 0
nanosec: 0
' 

[fujitatomoya]

@tonynajjar as far as i can tell, #1151 is nothing to do with ros2 topic pub because it did not change anything about it.

but the service is another thing.

[fujitatomoya]

i think root cause of this tab completion behavior is that #1151 changed some required positional arguments into optional arguments.

[peci1]

So, I don't really understand a few things.

First, what do I need to do to get the interactive selection from fzf? I've installed the latest rolling version and verified that I'm using the HEAD version of the package. However, when tab-tabbing, I only get the classical bash printout of options, not the nice interactive menu. I'm running off of Docker image ghcr.io/sloretz/ros:rolling-ros-base with a custom-built overlay with ros2cli.

I see some behavior changes towards what I asked here.

I confirm ros2 topic echo <tab><tab> autosuggests only topic names and not flags, which is great.

What I don't understand is that also the behavior of ros2 topic pub <tab><tab> changed when #1151 did not touch that verb. Maybe some underlying shared function was changed then?

Nevertheless, I confirm @fujitatomoya observations about ros2 topic pub behavior, which is now almost what I'd want. The only thing is that ros2 topic pub topic type prototype <tab><tab> suggests files in current folder and not flags. But if I add a dash, I can see the flags, so that is more or less okay.

ROS 2 service seems to be broken more than before:

ros2 service call /srv <tab><tab> lists files in current dir.

ros2 service call /srv half-written-type<tab> does nothing (I'm testing on a GetParameters service whose definition is definitely available in the system)

ros2 service call /srv /type <tab><tab> fills in the prototype which can actually be used

ros2 action send_goal seems to behave as I'd expect, though I could only test name and type completion.