Standardize error handling in CLI connection import

[Vegapunk-debug]

closes: None (No related issue)

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Description

This PR standardizes error handling for the airflow connections import CLI operation, aligning its behavior with airflow variables import.

Note: This PR was originally opened to address transaction overhead by batching commits, but based on maintainer feedback (@potiuk), it was pivoted to prioritize robust error handling over performance.

Previously, a single database or validation error during a bulk connection import would cause the entire command to fail.

This PR updates connection_command.py by wrapping the individual session.merge() and session.commit() operations inside a try...except block within the _import_helper loop. If an individual connection fails to import, it now prints the specific error, executes a session.rollback(), and safely continues to the next connection in the file.

• connection_command.py: Added per-item try/except block with session.rollback() to ensure single failures do not abort the entire batch import.
• variable_command.py: Reverted previous optimization attempts to maintain its existing, intentional per-item commit and error handling structure.

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[boring-cyborg]

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[potiuk]

This one does not need newsfragment.

[Vegapunk-debug]

@potiuk , I have completely removed the file now.

[Vegapunk-debug]

Hi @potiuk , I resolved the issue you mentioned, Can you please review the PR.

[potiuk]

Actually - some errors will ony be raised if we try to commit (and then individual variables are skipped), so I do not think that change is good -> if anything, connection import should be updated to also follow this pattern.

[potiuk]

There are usually small number of connections or variables to import - so this optimisation is really worse than handling individual commit errors

[Vegapunk-debug]

Hi @potiuk ,

Thank you for your guidance!

I have updated the pull request based on your feedback. I completely reverted the optimization attempt in variable_command.py. Instead, I've added a try...except block with session.rollback() in connection_command.py to ensure that it properly handles individual connection import failures, aligning it with the behavior of variable imports.

Please let me know if this looks good to go!

[potiuk]

It's different than variables. Can you use the same approach as there, please.

[potiuk]

Converted to draft for now.

[Copilot]

Pull request overview

This PR updates the airflow connections import CLI flow to handle per-connection database/merge failures without aborting the entire import, aligning the behavior more closely with the variables import command.

Changes:

• Wraps session.merge() + session.commit() in a per-item try/except, rolling back on failure and continuing to the next connection.
• Adds failure messaging for individual connection import errors.

[Vegapunk-debug]

One question regarding error handling:
variables_import uses print(... {e!r}), but this may expose sensitive information.

Would you prefer keeping it consistent with variables_import, or should we avoid printing the full exception here?

[Vegapunk-debug]

@potiuk ,
Updated the implementation to follow variables_import approach.