Update healthcheck Method to Support First-Party Mode Filters for Tester Plugin Integration

[hussain-t]

Feature Description

Update the healthcheck method in the First_Party_Mode class to support overrides for the health check logic. This enhancement will enable seamless integration with the Site Kit Tester Plugin, allowing developers and testers to simulate various server configurations and validate the behavior of the First-party mode feature.

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• The healthcheck method in the First_Party_Mode class should support dynamic overrides for FPFE and proxy script access checks.
• The overrides should be implemented using filter hooks to allow testers to simulate different server configurations.
• The default health check logic should remain intact and execute if no overrides are set.

Implementation Brief

In includes/Core/Tags/First_Party_Mode/First_Party_Mode.php:

• Update the First_Party_Mode::healthcheck method to allow dynamic overrides for:
  • FPFE health check result.
  • Proxy script access check result.
• Implement the following filter hooks to support the overrides:
  • googlesitekit_is_fpm_healthy
  • googlesitekit_is_fpm_script_access_enabled
• Add the filter hooks to the respective health check conditions.
• Finish and merge this PR.

Test Coverage

• No new tests are required for this change.

QA Brief

• Set up Site Kit with the firstPartyMode feature flag enabled.
• Run the following snippet in the JS console. Verify that isFPMHealthy and isScriptAccessEnabled are true in the returned response:

await googlesitekit.data.dispatch( "core/site" ).fetchGetFPMServerRequirementStatus()

• Create a PHP file in mu-plugins with the following content:

<?php

add_filter( 'googlesitekit_is_fpm_healthy', '__return_false' );
add_filter( 'googlesitekit_is_fpm_script_access_enabled', '__return_false' );

• Run the JS snippet again. This time, the isFPMHealthy and isScriptAccessEnabled properties should be false.

Changelog entry

[techanvil]

Thanks @hussain-t, the IB LGTM. It needed an estimate which I've set to 7 to allow for testing.

IB ✅

[techanvil]

@hussain-t actually, on reflection - googlesitekit_is_script_access_enabled is quite a generic name for a filter which is tightly coupled to FPM. I'd suggest we name it googlesitekit_is_fpm_script_access_enabled. WDYT?

[hussain-t]

Sure. Go for it, @techanvil 👍

[techanvil]

Thanks @hussain-t. I've updated the IB and the PR accordingly.

[hussain-t]

Closing this ticket as the tester plugin implementation was updated to leverage the WordPress option_ filter for overriding the health check logic, instead of introducing custom filters.