Closes #6312: Exclude youtube thumbnail from lazyload

[jeawhanlee]

Description

This PR excludes youtube thumbnail from lazyload

Fixes #6312

Type of change

• Enhancement (non-breaking change which improves an existing functionality).

Is the solution different from the one proposed during the grooming?

No

Checklists

Generic development checklist

• My code follows the style guidelines of this project, with adapted comments and without new warnings.
• I have added unit and integration tests that prove my fix is effective or that my feature works.
• The CI passes locally with my changes (including unit tests, integration tests, linter).
• Any dependent changes have been merged and published in downstream modules.
• If applicable, I have made corresponding changes to the documentation. Provide a link to the documentation.

Test summary

• I triggered all changed lines of code at least once without new errors/warnings/notices.
• I validated all Acceptance Criteria of the related issues. (If applicable, provide proof).
• I validated all test plan the QA Review asked me to.

[jeawhanlee]

For CR, I Backported PR from wp-media/rocket-lazyload-common#116

[Mai-Saad]

@jeawhanlee Thanks for the PR. Please find exploratory test notes below.
1- When tried to exclude https://i.ytimg.com/vi/8bUSQjuNedI/hqdefault.jpg from UI on this page https://new.rocketlabsqa.ovh/video-testing/ (LL image , LL video and preview image are already enabled), the image wasnot excluded from LL
2- If we set the filter to return Null, we will have this warning
[19-Jan-2024 15:13:01 UTC] PHP Warning: foreach() argument must be of type array|object, null given in /var/www/new.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Dependencies/RocketLazyload/Iframe.php on line 252
Can you please check 🙏

[jeawhanlee]

When tried to exclude https://i.ytimg.com/vi/8bUSQjuNedI/hqdefault.jpg from UI on this page https://new.rocketlabsqa.ovh/video-testing/ (LL image , LL video and preview image are already enabled), the image wasnot excluded from LL

@Mai-Saad I was checking this but if we support exclusion from the UI, it would exclude the YT iframe from being lazyloaded and we don't want that.
@piotrbak Do we add another UI for this or just leave this as a filter as it is.

[piotrbak]

@jeawhanlee Just to be sure, if we'd add i.ytimg.com/vi/8bUSQjuNedI/hqdefault.jpg to the UI we'd exclude the iframe? 🤔

Iframe doesn't have hqdefault.jpg in the source

[remyperona]

That exclusion wouldn't do anything. At the time we can manage the exclusion, the thumbnail is not created yet in the page (it's dynamically generated with JS, based on the YT ID).

[Mai-Saad]

@jeawhanlee Thanks for the update. Now we can exclude thumbnail image using UI or filter. However, we need to guard the filter from invalid values as now if set to null, we will have this error. can you please check 🙏

[08-Feb-2024 17:54:42 UTC] PHP Fatal error:  Uncaught TypeError: WP_Rocket\Engine\Media\Lazyload\Subscriber::add_exclusions(): Argument #1 ($exclusions) must be of type array, null given, called in /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/class-wp-hook.php on line 324 and defined in /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Engine/Media/Lazyload/Subscriber.php:459
Stack trace:
#0 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/class-wp-hook.php(324): WP_Rocket\Engine\Media\Lazyload\Subscriber->add_exclusions()
#1 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/plugin.php(205): WP_Hook->apply_filters()
#2 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Dependencies/RocketLazyload/Assets.php(275): apply_filters()
#3 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Dependencies/RocketLazyload/Assets.php(209): WP_Rocket\Dependencies\RocketLazyload\Assets->getYoutubeThumbnailScript()
#4 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Engine/Media/Lazyload/Subscriber.php(254): WP_Rocket\Dependencies\RocketLazyload\Assets->insertYoutubeThumbnailScript()
#5 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/class-wp-hook.php(324): WP_Rocket\Engine\Media\Lazyload\Subscriber->insert_youtube_thumbnail_script()
#6 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#7 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/plugin.php(517): WP_Hook->do_action()
#8 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/general-template.php(3068): do_action()
#9 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/themes/twentytwentyone/footer.php(78): wp_footer()
#10 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/template.php(790): require_once('...')
#11 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/template.php(725): load_template()
#12 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/general-template.php(92): locate_template()
#13 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/themes/twentytwentyone/archive.php(38): get_footer()
#14 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-includes/template-loader.php(106): include('...')
#15 /var/www/newer.rocketlabsqa.ovh/htdocs/wp-blog-header.php(19): require_once('...')
#16 /var/www/newer.rocketlabsqa.ovh/htdocs/index.php(17): require('...')
#17 {main}
  thrown in /var/www/newer.rocketlabsqa.ovh/htdocs/wp-content/plugins/wp-rocket/inc/Engine/Media/Lazyload/Subscriber.php on line 459

[Mai-Saad]

Related test plan https://wpmediaqa.testrail.io/index.php?/runs/view/814

[hanna-meda]

Relating issue found while testing this: #6451

[hanna-meda]

testrail-report-573.pdf