QOS python code for create_subscriber

edit

I've pull this from my code I use to get images from the RS camera (which requires a non-default QoS policy).

from rclpy.node import Node
from rclpy.qos import QoSProfile, QoSReliabilityPolicy, QoSHistoryPolicy

class MyNode(Node):
    def __init__(self):
        qos_profile = QoSProfile(
            reliability=QoSReliabilityPolicy.RMW_QOS_POLICY_RELIABILITY_BEST_EFFORT,
            history=QoSHistoryPolicy.RMW_QOS_POLICY_HISTORY_KEEP_LAST,
            depth=1
        )

        sub = Subscriber(
            self,
            Image,
            "rgb_img",
            qos_profile=qos_profile
        )
        sub.registerCallback(self._on_rgb)

    def _on_rgb(self, msg):
        ...

from rclpy import qos
self.speed_subscription = self.create_subscription(
    Int32,
    'distance',
    self.speed_listener_callback,qos.qos_profile_sensor_data)