Enable TransformListener node-based constructor in Intra-process enabled components

[roncapat]

Fixes #571

With this patch, TransformListener can be constructed using existing node references, when those nodes are in fact Intra-Process Enabled C++ ROS2 Components.

Intra-process communication is disabled per-subscription.

[FranzAlbers]

I'm running into a similar issue like #571, but with a StaticTransformBroadcaster.

Maybe this PR can be extended for the StaticTransformBroadcaster and TransformBroadcaster?

[roncapat]

@FranzAlbers so you compose a StaticTransformBroadcaster and it doesn't work when intra_process_Comms are enabled via component param?

EDIT: since I will probably try to compose some StaticTransformBroadcaster in my launchers, additional feedback from you could help me fix the problem you are mentioning.

[FranzAlbers]

@roncapat I want to compose a node with my camera driver, image_proc::RectifyNode, and image_proc::FlipNode (see ros-perception/image_pipeline#756) as components. To avoid unnecessary copies of the images, I want to use_intra_process_comms.

This works fine for my camera driver and the RectifyNode, but not for the FlipNode since it also uses a StaticTransformBroadcaster with transient_local durability. Thus, I am running into the following error during startup:
Component constructor threw an exception: intraprocess communication allowed only with volatile durability
Without the StaticTransformBroadcaster, intraprocess communications run fine for the FlipNode.

However, I quickly tried this myself by setting options.use_intra_process_comm = rclcpp::IntraProcessSetting::Disable; in line 67 of static_transform_broadcaster.h, but I am still running into the same error. Not sure what I am missing here.

[roncapat]

Ok, I will check also that. Seems a simple job, like what already included in this PR.

[FranzAlbers]

After cleaning and rebuilding the image_flip package it works as expected.

I think editing static_transform_broadcaster.h similarly to this PR should do the trick.

[roncapat]

@clalancette is there anything I should do to improve the PR?

[clalancette]

@clalancette is there anything I should do to improve the PR?

Can you please add in a test to show that this fixes the problem?

[roncapat]

Of course, I'll try (and write back if not able to figure out how to do it properly).

[roncapat]

@clalancette I force-pushed a commit with a new test triggering the issue with intraprocess enabled.

So that:

• if you check out the first commit, a new test appear (and fails)
• if you then check the second one, the new test passes

Hope this covers your request :)

[clalancette]

Can you please retarget this to the rolling branch? Once we have it in there, we can consider backporting to humble. Thanks.

[roncapat]

@clalancette yes (did a mess now with github portal trying to switch base branch...). During weekend I'll do the proper moves/rebase sorry :)

[roncapat]

What's the difference between Hpr and Rpr build?
Is it Humble vs. Rolling?

Anyway, I rebased on rolling :)

[clalancette]

What's the difference between Hpr and Rpr build?
Is it Humble vs. Rolling?

Yes, exactly. There is some bug here where if you change branches, it still tries to build on the old branch. So that's why the Hpr job is failing, but we can ignore that.

[clalancette]

One more small thing to fix, then I think this is ready for CI.

[clalancette]

(trailing whitespace makes uncrustify unhappy)

We are getting closer.

[clalancette]

(it's probably best if you run colcon test --packages-select tf2_ros before submitting again)

[roncapat]

Checked offline, this should be the last lint fix!

[clalancette]

CI:

• Linux
• Linux-aarch64
• Windows