Fix ROS 2 node initialization by removing invalid context manager usage#6129
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ayush-shirode wants to merge 1 commit intoros2:rollingfrom
Open
Fix ROS 2 node initialization by removing invalid context manager usage#6129ayush-shirode wants to merge 1 commit intoros2:rollingfrom
ayush-shirode wants to merge 1 commit intoros2:rollingfrom
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Summary This PR fixes an incorrect usage of rclpy.init() as a context manager in the static TF broadcaster node. The previous implementation used with rclpy.init():, which is not supported in ROS 2 Python and caused a runtime AttributeError: __enter__. Problem rclpy.init() does not implement Python’s context manager protocol (__enter__ / __exit__) Using it inside a with block causes the node to crash before spinning This prevented the static transform from being published on /tf_static Solution Replaced with rclpy.init(): with the correct ROS 2 lifecycle pattern: Explicit rclpy.init() Explicit rclpy.shutdown() in a finally block Preserved existing argument validation and exception handling Why this change is necessary ROS 2 Python initialization is a process-level operation, not a scoped resource. The explicit init/shutdown pattern is the officially supported and recommended approach and ensures predictable node lifecycle management. Impact Fixes runtime crash Allows static TF broadcaster to start correctly Aligns code with ROS 2 Python best practices Signed-off-by: ayush-shirode <ayushshirode2006@gmail.com>
fujitatomoya
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Jan 1, 2026
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fujitatomoya
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@ayush-shirode thanks for creating PR.
can you share the exact stack that generates the exception from this code in your local environment?
i am not sure if there is a problem that you are trying to explain here, because the same codes are used in else where, e.g https://github.com/ros2/examples/blob/rolling/rclpy/topics/minimal_publisher/examples_rclpy_minimal_publisher/publisher_local_function.py
Author
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Hello,
I was learning URDF using your documentation and followed all the steps
mentioned. I set up the ROS 2 environment, copied the state_publisher.py as
a node, configured the launch files, and successfully built the package
using colcon build. However, when I ran the launch file, I encountered a
runtime error. I’ve attached a screenshot of the error message for your
reference.
While reviewing the code, I noticed that rclpy.init() is being used inside
a with statement. Since the with construct in Python is intended for
context managers (objects implementing __enter__() and __exit__()), and
rclpy.init() is a plain initialization function that sets up global ROS 2
middleware state, this usage can lead to runtime issues such as AttributeError:
__enter__.
From my understanding, it may be safer to call rclpy.init() explicitly and
manage the node lifecycle using rclpy.shutdown() when the application is
ready to exit, as ROS 2 initialization is process-wide rather than scoped
to a block.
I wanted to check with you whether this change is required, or if there is
a specific reason the code is structured this way.
Thank you for your time and guidance.
Best regards,
Ayush Shirode
[image: image.png]
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Summary
This PR fixes an incorrect usage of rclpy.init() as a context manager in the static TF broadcaster node. The previous implementation used with rclpy.init():, which is not supported in ROS 2 Python and caused a runtime AttributeError: enter.
Problem
rclpy.init() does not implement Python’s context manager protocol (enter / exit)
Using it inside a with block causes the node to crash before spinning
This prevented the static transform from being published on /tf_static
Solution
Replaced with rclpy.init(): with the correct ROS 2 lifecycle pattern:
Explicit rclpy.init()
Explicit rclpy.shutdown() in a finally block
Preserved existing argument validation and exception handling
Why this change is necessary
ROS 2 Python initialization is a process-level operation, not a scoped resource. The explicit init/shutdown pattern is the officially supported and recommended approach and ensures predictable node lifecycle management.
Impact
Fixes runtime crash
Allows static TF broadcaster to start correctly
Aligns code with ROS 2 Python best practices
Description
Fixes # (issue)
Did you use Generative AI?
Additional Information