Move validation background tasks behind feature flag filter until Site Scanning is implemented

src/Validation/SavePostValidationEvent.php

@@ -11,6 +11,7 @@
 use AmpProject\AmpWP\BackgroundTask\BackgroundTaskDeactivator;
 use AmpProject\AmpWP\BackgroundTask\SingleScheduledBackgroundTask;
 use AmpProject\AmpWP\DevTools\UserAccess;
+use AmpProject\AmpWP\Infrastructure\Conditional;
 
 /**
  * SavePostValidationEvent class.
@@ -19,7 +20,7 @@
  *
  * @internal
  */
-final class SavePostValidationEvent extends SingleScheduledBackgroundTask {
+final class SavePostValidationEvent extends SingleScheduledBackgroundTask implements Conditional {
 
 	/**
 	 * Instance of URLValidationProvider
@@ -42,6 +43,15 @@ final class SavePostValidationEvent extends SingleScheduledBackgroundTask {
 	 */
 	const BACKGROUND_TASK_NAME = 'amp_single_post_validate';
 
+	/**
+	 * Check whether the service is currently needed.
+	 *
+	 * @return bool Whether needed.
+	 */
+	public static function is_needed() {
+		return URLValidationCron::is_needed();
+	}
+
 	/**
 	 * Class constructor.
 	 *
@@ -111,6 +121,7 @@ protected function should_schedule_event( $args ) {
 
 		$post = get_post( $id );
 
+		// @todo This needs to be limited to when the status is publish because otherwise the validation request will fail to be able to access the post, as the request is not authenticated.
 		if ( ! $post
 			||
 			wp_is_post_revision( $post )

src/Validation/URLValidationCron.php

@@ -10,6 +10,7 @@
 
 use AmpProject\AmpWP\BackgroundTask\BackgroundTaskDeactivator;
 use AmpProject\AmpWP\BackgroundTask\RecurringBackgroundTask;
+use AmpProject\AmpWP\Infrastructure\Conditional;
 
 /**
  * URLValidationCron class.
@@ -18,7 +19,7 @@
  *
  * @internal
  */
-final class URLValidationCron extends RecurringBackgroundTask {
+final class URLValidationCron extends RecurringBackgroundTask implements Conditional {
 
 	/**
 	 * ScannableURLProvider instance.
@@ -48,6 +49,33 @@ final class URLValidationCron extends RecurringBackgroundTask {
 	 */
 	const DEFAULT_SLEEP_TIME = 1;
 
+	/**
+	 * Check whether the service is currently needed.
+	 *
+	 * @return bool Whether needed.
+	 */
+	public static function is_needed() {
+		/**
+		 * Filters whether to enable URL validation cron tasks.
+		 *
+		 * This is a feature flag used to control whether the sample set of site URLs are scanned on a daily basis and
+		 * whether post permalinks are scheduled for immediate validation as soon as they are updated by a user who has
+		 * DevTools turned off. This conditional flag will be removed once Site Scanning is implemented, likely in v2.2.
+		 *
+		 * @link https://github.com/ampproject/amp-wp/issues/5750
+		 * @link https://github.com/ampproject/amp-wp/issues/4779
+		 * @link https://github.com/ampproject/amp-wp/issues/4795
+		 * @link https://github.com/ampproject/amp-wp/issues/4719
+		 * @link https://github.com/ampproject/amp-wp/issues/5671
+		 * @link https://github.com/ampproject/amp-wp/issues/5101
+		 * @link https://github.com/ampproject/amp-wp/issues?q=label%3A%22Site+Scanning%22
+		 *
+		 * @param bool $enabled Enabled.
+		 * @internal
+		 */
+		return apply_filters( 'amp_temp_validation_cron_tasks_enabled', false );
+	}
+
 	/**
 	 * Class constructor.
 	 *

tests/php/src/Validation/SavePostValidationEventTest.php

@@ -8,6 +8,7 @@
 use AmpProject\AmpWP\BackgroundTask\BackgroundTaskDeactivator;
 use AmpProject\AmpWP\BackgroundTask\SingleScheduledBackgroundTask;
 use AmpProject\AmpWP\DevTools\UserAccess;
+use AmpProject\AmpWP\Infrastructure\Conditional;
 use AmpProject\AmpWP\Infrastructure\Registerable;
 use AmpProject\AmpWP\Infrastructure\Service;
 use AmpProject\AmpWP\Tests\Helpers\AssertContainsCompatibility;
@@ -49,6 +50,17 @@ public function test__construct() {
 		$this->assertInstanceof( SavePostValidationEvent::class, $this->test_instance );
 		$this->assertInstanceof( Service::class, $this->test_instance );
 		$this->assertInstanceof( Registerable::class, $this->test_instance );
+		$this->assertInstanceof( Conditional::class, $this->test_instance );
+	}
+
+	/** @covers ::is_needed() */
+	public function test_is_needed() {
+		$this->assertFalse( SavePostValidationEvent::is_needed() );
+
+		add_filter( 'amp_temp_validation_cron_tasks_enabled', '__return_true' );
+		$this->assertTrue( SavePostValidationEvent::is_needed() );
+
+		remove_filter( 'amp_temp_validation_cron_tasks_enabled', '__return_true' );
 	}
 
 	/**

tests/php/src/Validation/URLValidationCronTest.php

@@ -4,6 +4,7 @@
 
 use AmpProject\AmpWP\BackgroundTask\BackgroundTaskDeactivator;
 use AmpProject\AmpWP\BackgroundTask\CronBasedBackgroundTask;
+use AmpProject\AmpWP\Infrastructure\Conditional;
 use AmpProject\AmpWP\Infrastructure\Registerable;
 use AmpProject\AmpWP\Infrastructure\Service;
 use AmpProject\AmpWP\Tests\Helpers\PrivateAccess;
@@ -45,13 +46,24 @@ public function test_register() {
 		$this->assertInstanceof( URLValidationCron::class, $this->test_instance );
 		$this->assertInstanceof( Service::class, $this->test_instance );
 		$this->assertInstanceof( Registerable::class, $this->test_instance );
+		$this->assertInstanceof( Conditional::class, $this->test_instance );
 
 		$this->test_instance->register();
 
 		$this->assertEquals( 10, has_action( 'admin_init', [ $this->test_instance, 'schedule_event' ] ) );
 		$this->assertEquals( 10, has_action( URLValidationCron::BACKGROUND_TASK_NAME, [ $this->test_instance, 'process' ] ) );
 	}
 
+	/** @covers ::is_needed() */
+	public function test_is_needed() {
+		$this->assertFalse( URLValidationCron::is_needed() );
+
+		add_filter( 'amp_temp_validation_cron_tasks_enabled', '__return_true' );
+		$this->assertTrue( URLValidationCron::is_needed() );
+
+		remove_filter( 'amp_temp_validation_cron_tasks_enabled', '__return_true' );
+	}
+
 	/** @covers ::schedule_event() */
 	public function test_schedule_event_with_no_user() {
 		$event_name = $this->call_private_method( $this->test_instance, 'get_event_name' );