<?php
/**
* Class ActionScheduler_Abstract_Schema
*
* @package Action_Scheduler
*
* @codeCoverageIgnore
*
* Utility class for creating/updating custom tables
*/
abstract class ActionScheduler_Abstract_Schema {
/**
* @var int Increment this value in derived class to trigger a schema update.
*/
protected $schema_version = 1;
/**
* @var string Schema version stored in database.
*/
protected $db_version;
/**
* @var array Names of tables that will be registered by this class.
*/
protected $tables = [];
/**
* Can optionally be used by concrete classes to carry out additional initialization work
* as needed.
*/
public function init() {}
/**
* Register tables with WordPress, and create them if needed.
*
* @param bool $force_update Optional. Default false. Use true to always run the schema update.
*
* @return void
*/
public function register_tables( $force_update = false ) {
global $wpdb;
// make WP aware of our tables
foreach ( $this->tables as $table ) {
$wpdb->tables[] = $table;
$name = $this->get_full_table_name( $table );
$wpdb->$table = $name;
}
// create the tables
if ( $this->schema_update_required() || $force_update ) {
foreach ( $this->tables as $table ) {
/**
* Allow custom processing before updating a table schema.
*
* @param string $table Name of table being updated.
* @param string $db_version Existing version of the table being updated.
*/
do_action( 'action_scheduler_before_schema_update', $table, $this->db_version );
$this->update_table( $table );
}
$this->mark_schema_update_complete();
}
}
/**
* @param string $table The name of the table
*
* @return string The CREATE TABLE statement, suitable for passing to dbDelta
*/
abstract protected function get_table_definition( $table );
/**
* Determine if the database schema is out of date
* by comparing the integer found in $this->schema_version
* with the option set in the WordPress options table
*
* @return bool
*/
private function schema_update_required() {
$option_name = 'schema-' . static::class;
$this->db_version = get_option( $option_name, 0 );
// Check for schema option stored by the Action Scheduler Custom Tables plugin in case site has migrated from that plugin with an older schema
if ( 0 === $this->db_version ) {
$plugin_option_name = 'schema-';
switch ( static::class ) {
case 'ActionScheduler_StoreSchema' :
$plugin_option_name .= 'Action_Scheduler\Custom_Tables\DB_Store_Table_Maker';
break;
case 'ActionScheduler_LoggerSchema' :
$plugin_option_name .= 'Action_Scheduler\Custom_Tables\DB_Logger_Table_Maker';
break;
}
$this->db_version = get_option( $plugin_option_name, 0 );
delete_option( $plugin_option_name );
}
return version_compare( $this->db_version, $this->schema_version, '<' );
}
/**
* Update the option in WordPress to indicate that
* our schema is now up to date
*
* @return void
*/
private function mark_schema_update_complete() {
$option_name = 'schema-' . static::class;
// work around race conditions and ensure that our option updates
$value_to_save = (string) $this->schema_version . '.0.' . time();
update_option( $option_name, $value_to_save );
}
/**
* Update the schema for the given table
*
* @param string $table The name of the table to update
*
* @return void
*/
private function update_table( $table ) {
require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
$definition = $this->get_table_definition( $table );
if ( $definition ) {
$updated = dbDelta( $definition );
foreach ( $updated as $updated_table => $update_description ) {
if ( strpos( $update_description, 'Created table' ) === 0 ) {
do_action( 'action_scheduler/created_table', $updated_table, $table );
}
}
}
}
/**
* @param string $table
*
* @return string The full name of the table, including the
* table prefix for the current blog
*/
protected function get_full_table_name( $table ) {
return $GLOBALS[ 'wpdb' ]->prefix . $table;
}
/**
* Confirms that all of the tables registered by this schema class have been created.
*
* @return bool
*/
public function tables_exist() {
global $wpdb;
$existing_tables = $wpdb->get_col( 'SHOW TABLES' );
$expected_tables = array_map(
function ( $table_name ) use ( $wpdb ) {
return $wpdb->prefix . $table_name;
},
$this->tables
);
return count( array_intersect( $existing_tables, $expected_tables ) ) === count( $expected_tables );
}
}