fix: use rai without rai_interfaces

[maciejmajek]

Purpose

While testing RAI installed with pip, I've come across a problem when running a very simple example:

from rai.communication.ros2 import ROS2Connector
  File "/home/mmajek/projects/rai_pip/.venv/lib/python3.12/site-packages/rai/communication/ros2/messages.py", line 31, in <module>
    if importlib.util.find_spec("rai_interfaces.msg") is None:
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib.util>", line 92, in find_spec
ModuleNotFoundError: No module named 'rai_interfaces'

Proposed Changes

Implements safe_find_spec to catch an error if package cannot be imported.

Issues

#607

Testing

• How was it tested, what were the results?

[boczekbartek]

Suggested change

	from importlib.machinery import ModuleSpec

[boczekbartek]

Suggested change

	def safe_find_spec(name):
	def safe_find_spec(name: str) -> ModuleSpec | None:

[boczekbartek]

I tried with python3.10 and python 3.13 and errors are not raised... When did you encounter this error?

>>> importlib.util.find_spec('aaa')
>>> importlib.util.find_spec('numpy')
ModuleSpec(name='numpy', loader=<_frozen_importlib_external.SourceFileLoader object at 0x10d9b69e0>, origin='/usr/local/lib/python3.10/site-packages/numpy/__init__.py', submodule_search_locations=['/usr/local/lib/python3.10/site-packages/numpy'])

[maciejmajek]

try aaa.aaa

[maciejmajek]

Hmm. I think we should rewrite all find_spec('rai_interfaces.*') to find_spec('rai_interfaces'). This way we will mitigate the problem without introducing custom safe_find_spec

[maciejmajek]

@boczekbartek I've refactored the solution to this problem to a mere two line changes (removing the submodule part of the rai_interfaces)

[boczekbartek]

Great! LGTM