import rclpy # Ros2를 python에서 사용할 수 있게 해주는 module from turtlesim.msg import Pose if not rclpy.ok(): # 또는 hasattr(rclpy, '_rclpy') 등으로 체크 rclpy.init() test_node = rclpy.create_node( 'sub_test' ) [WARN] [1744163682.294190713] [rcl.logging_rosout]: Publisher already registered for provided node name. If this is due to multiple nodes with the same name then all logs for that logger name will go out over the existing publisher. As soon as any node with that name is destructed it will unregister the publisher, preventing any further logs for that name from being published on the rosout topic.
def callback1 (data): print ( '---' ) print ( '/turtle1/pose :' ,data) print ( 'x : ' , data.x) print ( 'y : ' , data.y) print ( 'theta : ' , data.theta) cnt = 0 def callback2 (data): global cnt cnt += 1 print ( '>' , cnt, '-> X :' , data.x, ',Y : ' , data.y) if cnt > 3 : raise Exception ( 'subscription Stop' ) test_node.create_subscription(Pose, '/turtle1/pose' ,callback1, 10 ) <rclpy.subscription.Subscription at 0x755184771b70>
# node 연결 # <data_type> <topic_name> <callback> <QoS History> test_node.create_subscription(Pose, '/turtle1/pose' ,callback2, 10 ) <rclpy.subscription.Subscription at 0x7551847f0370>
rclpy.spin_once(test_node) > 6 -> X : 5.544444561004639 ,Y : 5.544444561004639
---------------------------------------------------------------------------
Exception Traceback (most recent call last)
Cell In[27], line 1
----> 1 rclpy.spin_once(test_node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py:206, in spin_once(node, executor, timeout_sec)
204 try:
205 executor.add_node(node)
--> 206 executor.spin_once(timeout_sec=timeout_sec)
207 finally:
208 executor.remove_node(node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:751, in SingleThreadedExecutor.spin_once(self, timeout_sec)
750 def spin_once(self, timeout_sec: float = None) -> None:
--> 751 self._spin_once_impl(timeout_sec)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:748, in SingleThreadedExecutor._spin_once_impl(self, timeout_sec)
746 handler()
747 if handler.exception() is not None:
--> 748 raise handler.exception()
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py:254, in Task.__call__(self)
251 if inspect.iscoroutine(self._handler):
252 # Execute a coroutine
253 try:
--> 254 self._handler.send(None)
255 except StopIteration as e:
256 # The coroutine finished; store the result
257 self.set_result(e.value)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:447, in Executor._make_handler.<locals>.handler(entity, gc, is_shutdown, work_tracker)
444 gc.trigger()
446 try:
--> 447 await call_coroutine(entity, arg)
448 finally:
449 entity.callback_group.ending_execution(entity)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:372, in Executor._execute_subscription(self, sub, msg)
370 async def _execute_subscription(self, sub, msg):
371 if msg:
--> 372 await await_or_execute(sub.callback, msg)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:107, in await_or_execute(callback, *args)
104 return await callback(*args)
105 else:
106 # Call a normal function
--> 107 return callback(*args)
Cell In[18], line 7, in callback2(data)
5 print('>', cnt, '-> X :' , data.x, ',Y : ', data.y)
6 if cnt > 3:
----> 7 raise Exception('subscription Stop')
Exception: subscription Stop
# 노드 구독 once는 한번만 그냥 spin은 무한 반복 rclpy.spin(test_node) > 1 -> X : 5.544444561004639 ,Y : 5.544444561004639
> 2 -> X : 5.544444561004639 ,Y : 5.544444561004639
> 3 -> X : 5.544444561004639 ,Y : 5.544444561004639
> 4 -> X : 5.544444561004639 ,Y : 5.544444561004639
---------------------------------------------------------------------------
Exception Traceback (most recent call last)
Cell In[20], line 2
1 # 노드 구독 once는 한번만 그냥 spin은 무한 반복
----> 2 rclpy.spin(test_node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py:226, in spin(node, executor)
224 executor.add_node(node)
225 while executor.context.ok():
--> 226 executor.spin_once()
227 finally:
228 executor.remove_node(node)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:751, in SingleThreadedExecutor.spin_once(self, timeout_sec)
750 def spin_once(self, timeout_sec: float = None) -> None:
--> 751 self._spin_once_impl(timeout_sec)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:748, in SingleThreadedExecutor._spin_once_impl(self, timeout_sec)
746 handler()
747 if handler.exception() is not None:
--> 748 raise handler.exception()
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py:254, in Task.__call__(self)
251 if inspect.iscoroutine(self._handler):
252 # Execute a coroutine
253 try:
--> 254 self._handler.send(None)
255 except StopIteration as e:
256 # The coroutine finished; store the result
257 self.set_result(e.value)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:447, in Executor._make_handler.<locals>.handler(entity, gc, is_shutdown, work_tracker)
444 gc.trigger()
446 try:
--> 447 await call_coroutine(entity, arg)
448 finally:
449 entity.callback_group.ending_execution(entity)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:372, in Executor._execute_subscription(self, sub, msg)
370 async def _execute_subscription(self, sub, msg):
371 if msg:
--> 372 await await_or_execute(sub.callback, msg)
File /opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py:107, in await_or_execute(callback, *args)
104 return await callback(*args)
105 else:
106 # Call a normal function
--> 107 return callback(*args)
Cell In[18], line 7, in callback2(data)
5 print('>', cnt, '-> X :' , data.x, ',Y : ', data.y)
6 if cnt > 3:
----> 7 raise Exception('subscription Stop')
Exception: subscription Stop