Description

Like in ROS 1, there should be a chance to control the replaying of a bag file.

spacebar should toggle the start/pause replaying.
s should solely spin the bag once.

Generally, as for now, there is no status feedback given when replaying a bag file. As a first step, there should be a message printed, whether the bag file is currently publishing data or not.

Completion criteria

• ros2 bag play uses keyboard_handler to receive key callbacks
• spacebar toggles pause/resume state for playback
• s does play_next
• ros2 bag play prints a help message when playback starts, explaining these controls

Related issues

#696

Implementation Notes

• May need to bloom-release keyboard_handler into Rolling - it is not yet in use.
• May need to expose keybindings to Python layer via Pybind - it makes sense for the CLI to define which keys do what, rather than hardcoding on the C++ end

Testing Notes

• May be difficult to do key-based end-to-end testing. It should be OK to mock the key callbacks