Avoid lots of uncessary exceptions during layout XML merge loading

[amenk]

Description

• Introduce a new function (for B/C compat we don't overwrite the protected _loadXmlString) to load and not throw an exception
• Use it in extract handlers -> no need to catch the exception any more

Related Pull Requests

See also: justbetter/magento2-sentry#113

Fixed Issues (if relevant)

No magento issue created.

Manual testing scenarios (*)

1. Install the sentry plugin
2. Have some invalid XML there
3. Exception is reported, even it is not necessary

Reason

When using tools like Sentry, because of there inner workings, such exceptions still might be reported. While this is not exactly the root cause, it's always cleaner to not throw an exception and immediately catch it, if invalid cases can happen often.

This might even improve performance a bit and improves developer's experience.

Remarks

There seems some invalid XML at that place in the code happen quite often - it might be also interesting to check if that can be avoided.

This is a simple, trivial change to the code and should not break anything, so hopefully this can get triaged quickly and without to much back-and-forth about the testing procedure :-)

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• [not applicable] All new or changed code is covered with unit/integration tests (if applicable)
• [not applicable] README.md files for modified modules are updated and included in the pull request if any README.md predefined sections require an update
• [waiting] All automated tests passed successfully (all builds are green)

Resolved issues:

1. resolves [Issue] Avoid lots of uncessary exceptions during layout XML merge loading #39877: Avoid lots of uncessary exceptions during layout XML merge loading

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[amenk]

@magento run all tests

[magento-automated-testing]

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[engcom-Hotel]

@magento run all tests

[engcom-Hotel]

Hello @amenk,

Thanks for the contribution!

Please fix the failed static test and also let us know if we can reproduce this original issue without using any 3rd party extensions.

Also please let us know which kind of exceptions are not generating after this fix.

Thanks

[amenk]

Almost two years later I am a bit out of context of this.

The issue was mostly visible with the sentry plugin.

Feel free to take over and fix the static tests ... :-) Thank you!

[engcom-Dash]

Hi @amenk ,

We attempted to reproduce the exception in Magento by applying some code level tweaks.

We observed that $this->updates[] property used in extractHandlers() method was consistently returning empty array[]. This is because initially it is set as empty and not getting updated anywhere prior to the extractHandlers() call.

To simulate the issue we pushed some invalid xml into $this->updates[] and verified the behaviour against the changes introduced in the PR.

On Magento 2.4-develop (Before applying the PR changes) We encountered the following exception:

After PR changes there were no exceptions were observed.

However, since _loadXmlString is invoked in multiple places in the file, there is possibility that similar exception could arise in other scenarios in the future.

However changes in the PR looks good to avoid the unnecessary exceptions during xml merge loading hence we can proceed with the PR. I am taking care of the failing static test cases.

Thank you!

[engcom-Dash]

@magento run all tests

[engcom-Dash]

@magento create issue

[engcom-Dash]

@engcom-Hotel I have fixed static test cases. Could you please review it?

Thanks

[engcom-Hotel]

Hello @engcom-Dash,

Please refer to the below review comments.

Thanks

[engcom-Dash]

@magento run all tests

[engcom-Dash]

@engcom-Hotel suggested changes has been made hence moving this back to pending review. could you please reviwe it once ?

[engcom-Hotel]

@magento run all tests

[engcom-Dash]

@magento run all tests

[engcom-Dash]

@amenk Thank you for the contirbution & collaboration!

✔️ QA Passed

Preconditions:
Install fresh magento 2.4-develop

Steps to reproduce:
Please refer comment #37570 (comment)

Before: ❌

After: ✔️

No warnings & error were logged/observed after switching to the PR Branch.

Build is Green hence moving this PR in Merge in Progress

[amenk]

@engcom-Dash Thank you for finalizing this!