[ROS2] best practice for composable node publishing data from blocking call

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Hi

I am converting a node from ROS1 to ROS2. This node uses a proprietary SDK to connect to a sensor. The function which reads from the sensor performs a blocking call.

This is the code in ROS1:

while (ros::ok()) {
  data =  get_data_from_sensor(); // may block indefinitely or a very short time
  publisher.publish(data);
  ros::spinOnce();
}

For the ROS2 conversion, I want to make use of the composable node architecture. get_data_from_sensor() will likely become a class member function, but how will I call it? When started as a component, ros::spin() is called on the node. As far as I know, no custom entry point exists.

Since the sensor events do not occur on a regular interval, using a timer does not seem feasible. In the node's constructor, I could create and run a thread with a loop like this:

while (rclcpp::ok()) {
  data =  get_data_from_sensor(); // may block indefinitely or a very short time
  publisher.publish(data);
}

However, this feels odd. My gut says, I am not adhering to some ROS2 paradigm. Is there a best practice for composable nodes publishing data from blocking calls at variable intervals?

Kind regards