[Bug] Iron and Rolling: errors on ros_discovery_info messages

[JEnoch]

Describe the bug

Following ros2/rmw_dds_common#68 the Gid type used in ros_discovery_info topic changed from char[24] data to char[16] data.

This leads the bridge to be incompatible with Iron and latest Rolling.
The incompatibility can be seen with such logs in the bridge:
[2023-11-29T14:51:27Z WARN zenoh_plugin_ros2dds::ros_discovery] Error receiving ParticipantEntitiesInfo on ros_discovery_info: invalid utf-8 sequence of 1 bytes from index 4

Or in a ROS Node:
[WARN] [1701269487.404903002] [rmw_cyclonedds_cpp]: Failed to parse type hash for topic 'ros_discovery_info' with type 'rmw_dds_common::msg::dds_::ParticipantEntitiesInfo_' from USER_DATA '(null)'.

To reproduce

In Iron, run zenoh-bridge-dds -f with any ROS Node and see the logs.

System info

• commit: 55a1385
• ROS distro: Iron and Rolling
• Platform: all

[Timple]

Is there any update here? On ROS Iron I'm still getting:

[rmw_cyclonedds_cpp]: Failed to parse type hash for topic 'rt/tf' with type 'tf2_msgs::msg::dds_::TFMessage_' from USER_DATA '(null)'.

[JEnoch]

I don't think the error message you get is related to this issue.
This issue is specifically related to the ros_discovery_info which is published and subscribed and decoded by the bridge.
You error message is related to the tf topic which the bridge is routing un-touched.
Therefore I think more of an incompatibility between your ROS Node publishing on tf topic and your ROS Node subscribing to this same topic.

Wrt. this issue, it has already been fixed for the zenoh-plugin-ros2dds: eclipse-zenoh/zenoh-plugin-ros2dds#21
And we advise all ROS 2 users to use this new zenoh-bridge-ros2dds instead of the zenoh-bridge-dds.
So I think we will fix this issue only if some ROS 2 user have good reasons to not switch to the new bridge.

[Timple]

Ah, we are actually using the zenoh-plugin-ros2dds. So my issue must indeed be different. Sorry for the confusion.