Ability to playback bags with unknown message types

[clalancette]

Description

Sometimes I am handed a bagfile that has messages I don't have the sources for. Right now if I try to play those bag files back with ros2 bag play, I get an error message like:

[ERROR] [1583183596.808870285] [rosbag2_transport]: Failed to play: package 'custom_pkg' not found, searching: [/home/ubuntu/ros2_ws/install/rosbag2, /home/ubuntu/ros2_ws/install/ros2bag, ...]

It would be nice if I could still play back these bag files, and ros2 bag play would just play the ones it could deserialize. Basically I am asking for this error to be downgraded to a warning, and skipping the messages that can't be played back.

I'm currently working around this by manually using sqlite3 to remove the messages I don't have the sources for.

Related Issues

None.

Completion Criteria

• Bag file with unknown messages can be played back, skipping the message types that are unknown. This errors out normally, but can be enabled with a flag (maybe --ignore-unknown-types)

Implementation Notes / Suggestions

Make the initial error messages about unknown messages a warning, and then skip those messages that can be deserialized during playback.

Testing Notes / Suggestions

Make sure there is a bag file with unknown message types, and that it can be played back.

[emersonknapp]

Good idea, perhaps an explicit argument to play, something like --ignore-unknown-types

[clalancette]

Good idea, perhaps an explicit argument to play, something like --ignore-unknown-types

I'd lean towards making it the default, with a warning, but a command-line option would work too.

[kielczykowski]

Shouldn't this issue be closed due to #592 and #394 or is the implementation still needed?

[emersonknapp]

Good catch - this is closed by #592