Do not ping URLs set to noindex by SEO plugins.

inc/namespace.php

@@ -211,6 +211,16 @@ function maybe_ping_indexnow( $new_status, $old_status, $post ): void {
 		return;
 	}
 
+	/*
+	 * Skip for noindexed posts that have never pinged IndexNow.
+	 *
+	 * Previously pinged URLs are still pinged to encourage removal from
+	 * search engines.
+	 */
+	if ( SEOCompat\is_noindex( $post ) && empty( get_post_ping_urls( $post ) ) ) {
+		return;
+	}
+
 	/*
 	 * Prevent double pings for block editor legacy meta boxes.
 	 */
@@ -325,15 +335,16 @@ function ping_indexnow( $post ) {
 	$current_url = get_permalink( $post );
 
 	/*
-	 * Only add the current URL if it is publicly viewable.
+	 * Only add the current URL if it is publicly viewable and indexed.
 	 *
-	 * This prevents unnecessary pings for private or draft posts in
-	 * which the current URL will 404. If the URL has been previously
-	 * pinged, it will be included in the list of URLs to ping as IndexNow
-	 * allows for new 404s to be pinged to encourage search engines
-	 * to remove the URL from their index.
+	 * This prevents unnecessary pings for new URLs that are either not
+	 * viewable (ie, will 404) or noindexed by an SEO plugin.
+	 *
+	 * If the URL has been previously sent to IndexNow it will still be
+	 * pinged to encourage search engines to de-index the page from their
+	 * search engine, either because it's a 404 or should not be listed.
 	 */
-	if ( is_post_publicly_viewable( $post ) && ! in_array( $current_url, $url_list, true ) ) {
+	if ( is_post_publicly_viewable( $post ) && ! SEOCompat\is_noindex( $post ) && ! in_array( $current_url, $url_list, true ) ) {
 		$url_list[] = get_permalink( $post );
 	}
 
@@ -442,7 +453,17 @@ function async_ping_indexnow( $post ) {
 
 	$post_id = $post->ID;
 
+	/**
+	 * Filter the delay (in seconds) before the asynchronous ping runs.
+	 *
+	 * @param int $delay The delay in seconds. Default is 10 seconds.
+	 */
+	$delay = apply_filters( 'simple_search_submission_async_wait', 10, $post );
+
+	// Revert delay to default if it isn't numeric.
+	$delay = is_numeric( $delay ) ? (int) $delay : 10;
+
 	if ( ! wp_next_scheduled( 'simple_search_submission_async_ping', array( $post_id ) ) ) {
-		wp_schedule_single_event( time() + 5, 'simple_search_submission_async_ping', array( $post_id ) );
+		wp_schedule_single_event( time() + $delay, 'simple_search_submission_async_ping', array( $post_id ) );
 	}
 }

inc/seo-compat.php

@@ -0,0 +1,88 @@
+<?php
+/**
+ * Simple Search Submission for IndexNow
+ *
+ * @package           SimpleSearchSubmission
+ */
+
+namespace PWCC\SimpleSearchSubmission\SEOCompat;
+
+/**
+ * Determine if a post is set to noindex by an SEO plugin.
+ *
+ * @param \WP_Post|int $post The post object or ID.
+ * @return bool True if the post is set to noindex, false otherwise.
+ */
+function is_noindex( $post ) {
+	$post = get_post( $post );
+	if ( ! $post ) {
+		return true; // No post found, treat as noindex.
+	}
+
+	/*
+	 * Check in order of number of active installs.
+	 *
+	 * To optimize performance for the majority of users, the
+	 * checks are ordered by the popularity of the SEO plugins.
+	 *
+	 * Popularity data from the WordPress plugin repository.
+	 */
+
+	// Check for Yoast SEO noindex (10 million+).
+	if ( is_yoast_noindex( $post ) ) {
+		return true;
+	}
+
+	// Check All in One SEO noindex (3 million+).
+	if ( is_aioseo_noindex( $post ) ) {
+		return true;
+	}
+
+	return false; // Default to not noindex.
+}
+
+/**
+ * Check Yoast SEO noindex status.
+ *
+ * @param \WP_Post|int $post The post object or ID.
+ * @return bool True if Yoast SEO sets the post to noindex, false otherwise.
+ */
+function is_yoast_noindex( $post ) {
+	if ( ! function_exists( 'YoastSEO' ) ) {
+		return false; // Yoast SEO is not active.
+	}
+
+	$post    = get_post( $post );
+	$post_id = $post->ID;
+
+	$robots = YoastSEO()->meta->for_post( $post_id )->robots;
+
+	if ( ! isset( $robots['index'] ) ) {
+		return false; // No index directive found.
+	}
+
+	return 'noindex' === $robots['index'];
+}
+
+/**
+ * Check All in One SEO noindex status.
+ *
+ * @param \WP_Post|int $post The post object or ID.
+ * @return bool True if AIOSEO sets the post to noindex, false otherwise.
+ */
+function is_aioseo_noindex( $post ) {
+	if ( ! function_exists( 'aioseo' ) ) {
+		return false; // AIOSEO is not active.
+	}
+
+	$post    = get_post( $post );
+	$post_id = $post->ID;
+
+	$post_meta = aioseo()->meta->metaData->getMetaData( $post_id );
+
+	if ( ! $post_meta->robots_default && isset( $post_meta->robots_noindex ) ) {
+		return $post_meta->robots_noindex;
+	}
+
+	return aioseo()->helpers->isPostTypeNoindexed( get_post_type( $post ) );
+}

simple-search-submission.php

@@ -39,6 +39,7 @@
 namespace PWCC\SimpleSearchSubmission;
 
 require_once __DIR__ . '/inc/namespace.php';
+require_once __DIR__ . '/inc/seo-compat.php';
 
 // Run late to give themes and plugins a chance to set up asynchronous pings.
 add_action( 'after_setup_theme', __NAMESPACE__ . '\\bootstrap', 20 );