fails to detect ros1 since Feature/rosbags support #31

[jgvictores]

Hi!
2526fa8 which was merged at #31 introduced from builtin_interfaces.msg import Time at

pypcd4/src/pypcd4/pypcd4.py

Line 611 in 2526fa8

from builtin_interfaces.msg import Time

which from what I've been checking belongs to ROS2. I'm working on a project that involves ROS1 (Noetic), which is not detected (in fact rosbags is recommended, which at time of writing defaults to ROS2 Dashing).

Pypi-wise, this is present in pypcd4 1.2.0, so I ended up manually commenting out the culprit line in cd /usr/local/lib/python3.8/dist-packages/pypcd4/pypcd4.py and everything works perfectly (in fact, I first tried downgrading to pypcd4 1.1.0 but colors were all messed up in rviz).

I understand that the correct way to go would be a Pull Request, but code-wise it's simply commenting out one line; however, I understand that though it works for me on Noetic, it would require some tests to not break anybody else's workflow (e.g. Melodic, ROS2...), so just writing here as a means of documentation in case anyone else runs into this issue. Cheers and thank you for the great open source!

[jacoblambert]

Sorry about this and the late reply.

ROS libraries break my testing pipeline, so it's a bit tricky, but I didn't do a good job testing it on my end, so sorry about that. I also honestly didn't consider ROS1 much with it being EOL as of this month (May 31st!!) but we understand it will continue to be used for a while.

We are putting out a PR addressing this. For reference, after this PR, pypcd4 now prioritizes ROS messages over Rosbags message, since you can't publish rosbags messages. It will try to load ROS messages, distinguishing between ROS1 and ROS2. If ROS messages are not found, it will default to Rosbags.

I tested Rosbags, ROS1, ROS2, ROS1+Rosbags and ROS2+Rosbags without issue, but of more issues should arise, let us know and we'll consider reverting this change altogether and only supporting rosbags.

See: #36