woocommerce-paypal-payments/modules/ppcp-webhooks/src/WebhookOrchestrator.php

<?php
declare( strict_types = 1 );

namespace WooCommerce\PayPalCommerce\Webhooks;

use Psr\Log\LoggerInterface;

/**
 * Orchestrates webhook operations with lock protection to prevent race conditions.
 */
class WebhookOrchestrator {

	private const LOCK_KEY      = 'ppcp_webhook_operation_lock';
	private const LOCK_DURATION = 60;

	private LoggerInterface $logger;

	public function __construct( LoggerInterface $logger ) {
		$this->logger = $logger;
	}

	/**
	 * Execute a webhook operation with lock protection.
	 *
	 * @param string   $action    Which operation is started (for logging).
	 * @param callable $operation The operation to execute.
	 * @return mixed The result of the operation, or null if locked.
	 */
	public function with_lock( string $action, callable $operation ) {
		if ( $this->is_locked() ) {
			$this->logger->info( "Webhook operation '$action' skipped - lock held by another process." );

			return null;
		}

		$this->acquire_lock( $action );

		try {
			$this->logger->debug( "Webhook operation '$action' started." );

			return $operation();
		} finally {
			$this->release_lock( $action );
		}
	}

	private function is_locked(): bool {
		return false !== get_transient( self::LOCK_KEY );
	}

	private function acquire_lock( string $action ): void {
		set_transient( self::LOCK_KEY, true, self::LOCK_DURATION );
		$this->logger->debug( "Webhook lock acquired for '$action'." );
	}

	private function release_lock( string $action ): void {
		delete_transient( self::LOCK_KEY );
		$this->logger->debug( "Webhook lock released for '$action'." );
	}
}