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<?php |
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/** |
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* WordPress-backed Setup Wizard operation lock. |
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* |
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* @package Booking Calendar |
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*/ |
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|
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if ( ! defined( 'ABSPATH' ) ) { |
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exit; |
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} |
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|
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/** |
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* Serialize save operations for one storage context and step. |
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*/ |
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final class WPBC_Setup_Wizard_WordPress_Operation_Lock implements WPBC_Setup_Wizard_Operation_Lock { |
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|
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const LOCK_TTL = 120; |
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|
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/** |
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* Acquire one option-backed lock through WordPress' atomic add operation. |
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* |
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* Expired records are removed once and acquisition is retried. The option is |
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* non-autoloaded and contains only opaque hashes and timestamps. |
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* |
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* @param string $lock_scope Opaque checkpoint storage scope. |
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* @param string $step_id Stable step identifier. |
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* @param string $operation_id Stable operation identifier. |
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* |
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* @return string|WP_Error Opaque lock token or busy error. |
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*/ |
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public function acquire( $lock_scope, $step_id, $operation_id ) { |
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$option_name = $this->get_option_name( $lock_scope, $step_id ); |
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$lock_token = function_exists( 'wp_generate_uuid4' ) ? wp_generate_uuid4() : uniqid( 'wpbc_', true ); |
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$lock_record = array( |
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'token' => $lock_token, |
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'operation_id' => sanitize_key( $operation_id ), |
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'expires_at' => time() + self::LOCK_TTL, |
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); |
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|
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if ( add_option( $option_name, $lock_record, '', false ) ) { |
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return $lock_token; |
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} |
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|
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$existing_lock = get_option( $option_name, array() ); |
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if ( $this->delete_expired_lock( $option_name, $existing_lock ) ) { |
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if ( add_option( $option_name, $lock_record, '', false ) ) { |
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return $lock_token; |
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} |
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} |
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|
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return new WP_Error( 'wpbc_setup_wizard_operation_locked', __( 'This Setup Wizard step is already being saved. Wait for it to finish, then try again.', 'booking' ) ); |
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} |
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|
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/** |
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* Release a lock only when its opaque token still matches. |
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* |
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* @param string $lock_scope Opaque checkpoint storage scope. |
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* @param string $step_id Stable step identifier. |
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* @param string $lock_token Opaque token returned by acquire(). |
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* |
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* @return void |
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*/ |
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public function release( $lock_scope, $step_id, $lock_token ) { |
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$option_name = $this->get_option_name( $lock_scope, $step_id ); |
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$current_lock = get_option( $option_name, array() ); |
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|
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if ( is_array( $current_lock ) && isset( $current_lock['token'] ) && hash_equals( (string) $current_lock['token'], (string) $lock_token ) ) { |
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$this->delete_lock_record( $option_name, $current_lock ); |
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} |
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} |
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|
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/** |
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* Build a bounded site-option name without exposing context identifiers. |
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* |
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* @param string $lock_scope Opaque checkpoint storage scope. |
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* @param string $step_id Stable step identifier. |
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* |
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* @return string WordPress option name. |
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*/ |
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private function get_option_name( $lock_scope, $step_id ) { |
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return 'wpbc_setup_wizard_step_lock_' . md5( (string) $lock_scope . '|' . sanitize_key( $step_id ) ); |
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} |
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|
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/** |
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* Atomically remove the exact expired record observed by this request. |
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* |
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* A normal read-then-delete sequence could remove a fresh lock created by a |
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* competing request between those operations. Matching both option name and |
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* serialized value limits deletion to the stale record that was read. The |
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* option cache is cleared only after that exact row was removed. |
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* |
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* @param string $option_name Internal lock option name. |
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* @param mixed $lock_record Observed lock record candidate. |
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* |
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* @return bool True when this request removed the observed expired record. |
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*/ |
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private function delete_expired_lock( $option_name, $lock_record ) { |
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if ( ! is_array( $lock_record ) || ! isset( $lock_record['expires_at'] ) || (int) $lock_record['expires_at'] >= time() ) { |
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return false; |
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} |
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|
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return $this->delete_lock_record( $option_name, $lock_record ); |
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} |
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|
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/** |
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* Atomically delete one exact lock record and clear its option cache. |
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* |
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* @param string $option_name Internal lock option name. |
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* @param array<string,mixed> $lock_record Exact record observed by the caller. |
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* |
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* @return bool True when the exact record was deleted. |
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*/ |
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private function delete_lock_record( $option_name, array $lock_record ) { |
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global $wpdb; |
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|
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// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching -- Atomic compare-and-delete is required; the exact option cache is cleared below. |
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$deleted_rows = $wpdb->query( |
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$wpdb->prepare( |
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"DELETE FROM {$wpdb->options} WHERE option_name = %s AND option_value = %s", |
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$option_name, |
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maybe_serialize( $lock_record ) |
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) |
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); |
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|
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if ( 1 !== (int) $deleted_rows ) { |
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return false; |
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} |
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|
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wp_cache_delete( $option_name, 'options' ); |
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wp_cache_delete( 'notoptions', 'options' ); |
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|
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return true; |
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} |
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} |
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|
