/home/egir5919/public_html/wp-content/plugins/surerank/inc/functions/rest-observation.php
<?php
/**
* Rest_Observation
*
* Records whether SureRank's REST API is reachable from real save
* attempts. Two writers:
*
* - Rest_Observation::mark_blocked() is called from the AJAX fallback
* handlers in inc/ajax/save-endpoints.php. Reaching an AJAX handler
* means the JS middleware fell back from REST after a transport
* failure, which is evidence REST is blocked.
* - Rest_Observation::mark_reachable() is called from the REST save
* endpoints (inc/api/post.php, inc/api/term.php, inc/api/admin.php)
* on a successful save. Reaching REST at all is evidence REST works.
*
* Both writers are gated by a short transient lock so burst saves on
* editor-heavy sites do not hammer wp_options. Only state changes are
* written; repeat writes of the same value short-circuit.
*
* The stored option is consumed by Rest_Site_Health to surface REST
* reachability in Tools -> Site Health.
*
* @package SureRank\Inc\Functions
* @since 1.7.2
*/
namespace SureRank\Inc\Functions;
if ( ! defined( 'ABSPATH' ) ) {
exit; // Exit if accessed directly.
}
/**
* REST reachability observation writer.
*
* @since 1.7.2
*/
class Rest_Observation {
/**
* Option name storing the last observed reachability state.
* Values: 'yes' | 'no'. Absence means "not yet observed" and
* Rest_Site_Health treats that as healthy (no signal to surface).
*/
public const OPTION_NAME = 'surerank_rest_ok';
/**
* Transient lock key that rate-limits writes. A brief lock is
* enough to collapse burst-save storms into one write per site
* per window without blocking the actual save path.
*/
private const LOCK_KEY = 'surerank_rest_ok_write_lock';
/**
* Window (seconds) during which a second write of the same class
* is skipped.
*/
private const LOCK_TTL = 60;
/**
* Record that REST is currently blocked (AJAX fallback just ran).
*
* @return void
*/
public static function mark_blocked(): void {
self::maybe_write( 'no' );
}
/**
* Record that REST is currently reachable (a REST save just
* completed successfully).
*
* @return void
*/
public static function mark_reachable(): void {
self::maybe_write( 'yes' );
}
/**
* Write the given state if it differs from what's stored AND no
* write has happened in the last LOCK_TTL seconds.
*
* Not security-sensitive; a benign TOCTOU race between two
* concurrent writes converges on the correct value within one
* subsequent save.
*
* @param string $value Either 'yes' or 'no'.
* @return void
*/
private static function maybe_write( string $value ): void {
$current = get_option( self::OPTION_NAME, null );
if ( $current === $value ) {
return;
}
if ( false !== get_transient( self::LOCK_KEY ) ) {
return;
}
set_transient( self::LOCK_KEY, 1, self::LOCK_TTL );
update_option( self::OPTION_NAME, $value, false );
}
}