When publishing multiple Diagnostics messages on the same topic but with a different key, messages are being dropped. It is visible in the screenshot below, where 'b' has no dropped messages, but 'a' has. You can see the sine wave for 'a' is oddly shaped.
I managed to create a minimal node which can reproduce this problem. It's based off of the ROS2 Galactic tutorial, with diagnostic_msgs added as dependency.
from diagnostic_msgs.msg import DiagnosticArray, DiagnosticStatus, KeyValue
import rclpy
from rclpy.node import Node
class MinimalPublisher(Node):
def __init__(self):
super().__init__('minimal_publisher')
self.diagnostics_publisher = self.create_publisher(DiagnosticArray, '/diagnostics', 10)
timer_period = 0.5 # seconds
self.timer = self.create_timer(timer_period, self.timer_callback)
self.sine_values = [500, 794, 976, 976, 794, 500, 206, 24, 24, 206]
self.i = 0
def timer_callback(self):
self._publish_message('a')
self._publish_message('b')
self.i += 1
if self.i == len(self.sine_values):
self.i = 0
def _publish_message(self, name):
array = DiagnosticArray()
array.header.stamp = self.get_clock().now().to_msg()
status = DiagnosticStatus(level=DiagnosticStatus.OK, name=name, message='OK')
status.values.append(KeyValue(key='sine', value=str(self.sine_values[self.i])))
array.status.append(status)
self.diagnostics_publisher.publish(array)
def main(args=None):
rclpy.init(args=args)
minimal_publisher = MinimalPublisher()
rclpy.spin(minimal_publisher)
minimal_publisher.destroy_node()
rclpy.shutdown()
if __name__ == '__main__':
main()
When publishing multiple Diagnostics messages on the same topic but with a different key, messages are being dropped. It is visible in the screenshot below, where 'b' has no dropped messages, but 'a' has. You can see the sine wave for 'a' is oddly shaped.
I managed to create a minimal node which can reproduce this problem. It's based off of the ROS2 Galactic tutorial, with
diagnostic_msgsadded as dependency.