Improvement: Use shutdown() Before close() in connection.py

[allrob23]

Pull Request check-list

Please make sure to review and check all of these items:

• Do tests and lints pass with this change?
• Do the CI tests pass with this change (enable it first in your forked repo and wait for the github action build to finish)?
• Is the new or changed code fully tested?
• Is a documentation update included (if this change modifies existing APIs, or introduces new ones)?
• Is there an example added to the examples folder (if applicable)?
• Was the change added to CHANGES file?

Description of change

This PR improves socket resource management by implementing the recommended shutdown-then-close pattern in error handling scenarios.

Benefits

1. Ensures proper connection termination – shutdown() initiates the TCP termination sequence before releasing resources.
2. Prevents potential resource leaks – Reduces the risk of lingering sockets in edge cases.
3. Enhances network reliability – Ensures pending data is handled correctly before closing.
4. Aligns with Python best practices – Follows Python’s official socket documentation recommendations.

Technical Details

The Python documentation explicitly states:

"close() releases the resource associated with a connection but does not necessarily close the connection immediately. If you want to close the connection in a timely fashion, call shutdown() before close()."
Python socket documentation

This change introduces properly exception-handled shutdown() calls before close() to ensure sockets are gracefully terminated, even when exceptions occur.

Impact

This is a low-risk change that improves resource cleanup and robustness. The modification is minimal but aligns the codebase with networking best practices, ensuring better socket lifecycle management.

[petyaslavova]

Hi @allrob23 thank you for your contribution! We’ll review your change soon.