Organize nodes view by namespaces

[acschaefer]

Thank you for this great piece of software!

I have been using node_manager for some time now. In large projects, nodes are often organized in namespaces, for example

ground_robot/lidar/velodyne_driver
ground_robot/vision/camera_front_driver/rgb_rectifier
ground_robot/vision/camera_front_driver/nir_rectifier
ground_robot/camera_back_driver
aerial_robot/flight_controller
aerial_robot/vision/camera_1
aerial_robot/vision/camera_2
...

That is what the node_manager's node view looks like. However, I find it hard to get an overview over all the nodes, if I have a couple of dozen running. So why not use the namespace topology to create a nice nested node view like this:

ground_robot/
    lidar/
        velodyne_driver
    vision/
        camera_front_driver/
            rgb_rectifier
            nir_rectifier
        camera_back_driver
aerial_robot/
    flight_controller
    vision/
        camera_1
        camera_2
...

Capability grouping is not really an alternative. I would end up with two levels only, and I would need to iterate over all nodes and add the capability_group parameter to each of them. If the topology of the namespace changed, I would have to change all capability_group tags again.

[atiderko]

Nice to hear that the node manager is also useful to others!

We didn't need the grouping by namespaces, because we use only two level :-) But it is good point for all others with deeper namespacing. I will put this suggestion on my todo!

[acschaefer]

Great, thank you!

[atiderko]

I added a branch test_nsgroup with new grouping. Can you take a look on the node manager. Is it what you imagine?

[acschaefer]

Thank you for reacting so quickly! I checked out the test_nsgroup branch and reinstalled the node manager. However, I cannot see any changes in the nodes view compared to the previous version (see screenshot below).

Hopefully, you can reproduce that by loading the little test launch file I wrote. It is contained in my pull request.

[atiderko]

Thank you for testing!

But I can not reproduce your issue, see image:

I removed a warning while loading this file and updated a version tag. After update you should see the same node manager version if you click on info button. Only to see if the same version is started ;-)

[acschaefer]

Yes, you were right, I was still using the old version. With your new version, it worked like a charm! =) I also added some parameters to the dummy nodes in the test script in order to make sure they start up alright. They do:

[acschaefer]

This new feature makes it a lot easier to get an overview over large ROS systems.

I think namespace grouping could be a good idea for topics and services as well. Would the changes you made to the nodes view be easily transferable to the topics and services views?

As a motivational example, here is the beginning of my current topics view:

[atiderko]

good to hear that it works.

Unfortunately it is not so easily to transfer, but it is also on my todo! I will merge this changes into the master branch after topic and service view is changed.

In the meantime you can test the topic view and new group/node highlighting ;-)

[acschaefer]

Sounds great! I am testing every day. =)

One minor remark: Should namespaces that contain only one node be opened automatically in the nodes view?

[atiderko]

I made some changes:

• no groups with one node are created
• namespace groups for topics
• namespace groups for services

[acschaefer]

I have been testing for the last few days and it worked great!

Just one minor remark: As all topics and services start with a slash, I always see a single / as top node. I suggest to ignore the slash prefix when creating namespace groups.

I attached a screenshot for illustration:

[atiderko]

thank you for testing!

Since I can not easily replace the root item of the TreeView I changed the name of /

Can you try again, please?

[acschaefer]

Thank you for updating the code so quickly!

The screenshot below shows the services view after updating to the most recent version of node_manager. The slash at the top is still there. Moreover, I do not understand the subdivision of services into / and {SYSTEM} yet. Many services are listed as system services which I would not consider being core ROS services.

I hope this is helpful. =)

[atiderko]

I put get_loggers and set_logger_level to {SYSTEM} group since this services are created by core ROS for each node and you did not actively use them.

The same is for topics: rosout and rosout_agg are always there, so I put them to {SYSTEM} group.

/ in services was also changed, but in the second commit. Perhaps you use not the newest commit?

[acschaefer]

Sorry, it happened again! =) With catkin, you can have an installed version that is different from the built, but not installed version.

So I upgraded to your newest version and it works perfectly! I also understood the distinction between system services and other services. That makes sense.

Thank you for this nice extension!

[acschaefer]

Here comes some more feedback from testing the namespace grouping.

I have a project with about 20 nodes and around 100 topics. When I select a node in the node view and then try to change to the services view, the node_manager crashes reproducibly every time.

[atiderko]

Thanky for testing!

I fixed the bug on change to service view.

[acschaefer]

Confirmed! The bug is gone. I really like the namespace grouping.

[acschaefer]

I found a bug in the topics view: The publisher/subscriber counts are not correct. Take a look at the following screenshot. Although robot/joint_states is published by Gazebo as shown in the panel on the left-hand side, the publisher count for the topic displayed in the main panel is 0.

[atiderko]

Thank you for reporting! I fixed this issue.

[acschaefer]

Confirmed, it is fixed!

[atiderko]

thank you for confirmation!

I merged this branch into the master branch.