Fix invalid import of get_parameter_value in rosapi for ROS2 Jazzy.

[Oberacda]

Public API Changes

None

Description

The import ros2param.get_parameter_value is no longer valid in ROS2 jazzy.
The code was removed with PR ros2/ros2cli#866, with the suggested alternative being the import from rclpy.
As get_parameter_value was implemented in rclpy for ROS2 versions before Jazzy, this should not break older ROS2 distros.

#926

[sea-bass]

LGTM. This works for rolling (i checked, Iron and later) but we'll have to make another branch for humble since it does not work there.

[faev999]

I am still getting that same error: " ImportError: cannot import name 'get_parameter_value' from 'ros2param.api'"
when trying to launch the rosbridge ros2 launch rosbridge_server rosbridge_websocket_launch.xml. I am using the bridge inside a Docker image that I build like this:

FROM ros:rolling-ros-core

RUN apt-get update && apt-get install -y --no-install-recommends \
    ros-${ROS_DISTRO}-rosbridge-server \
 ...

[sea-bass]

This was only merged to the repo, not released as binaries. You should clone this repo and build it from source.

[Rayman]

Can we get a new release for jazzy that includes this fix?

[faev999]

This was only merged to the repo, not released as binaries. You should clone this repo and build it from source.

When trying to build from source, I got this error:

1.614 E: Unable to locate package ros-rolling-example-interfaces
1.614 ERROR: the following rosdeps failed to install
1.614   apt: command [apt-get install -y ros-rolling-example-interfaces] failed
1.616 executing command [apt-get install -y ros-rolling-example-interfaces]

which is being trigger by this command: rosdep install --from-paths src --ignore-src --rosdistro=$ROS_DISTRO -y

If I switch from Rolling to Jazzy, building from source works, and launching the bridge also works.