<?php
/**
* Part of the Joomla Framework Database Package
*
* @copyright Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
namespace Joomla\Database;
/**
* Joomla Framework Database Importer Class
*
* @since 1.0
*/
abstract class DatabaseImporter
{
/**
* An array of cached data.
*
* @var array
* @since 1.0
*/
protected $cache = ['columns' => [], 'keys' => []];
/**
* The database connector to use for exporting structure and/or data.
*
* @var DatabaseInterface
* @since 1.0
*/
protected $db;
/**
* The input source.
*
* @var mixed
* @since 1.0
*/
protected $from = [];
/**
* The type of input format.
*
* @var string
* @since 1.0
*/
protected $asFormat = 'xml';
/**
* An array of options for the exporter.
*
* @var \stdClass
* @since 1.0
*/
protected $options;
/**
* Constructor.
*
* Sets up the default options for the importer.
*
* @since 1.0
*/
public function __construct()
{
$this->options = new \stdClass();
// Set up the class defaults:
// Import with only structure
$this->withStructure();
// Export as XML.
$this->asXml();
// Default destination is a string using $output = (string) $importer;
}
/**
* Set the output option for the importer to XML format.
*
* @return $this
*
* @since 1.0
*/
public function asXml()
{
$this->asFormat = 'xml';
return $this;
}
/**
* Checks if all data and options are in order prior to importer.
*
* @return $this
*
* @since 1.0
* @throws \RuntimeException
*/
abstract public function check();
/**
* Specifies the data source to import.
*
* @param \SimpleXMLElement|string $from The data source to import, either as a SimpleXMLElement object or XML string.
*
* @return $this
*
* @since 1.0
*/
public function from($from)
{
$this->from = $from;
return $this;
}
/**
* Get the SQL syntax to add a column.
*
* @param string $table The table name.
* @param \SimpleXMLElement $field The XML field definition.
*
* @return string
*
* @since 1.0
*/
protected function getAddColumnSql($table, \SimpleXMLElement $field)
{
return 'ALTER TABLE ' . $this->db->quoteName($table) . ' ADD COLUMN ' . $this->getColumnSQL($field);
}
/**
* Get alters for table if there is a difference.
*
* @param \SimpleXMLElement $structure The XML structure of the table.
*
* @return array
*
* @since 2.0.0
*/
abstract protected function getAlterTableSql(\SimpleXMLElement $structure);
/**
* Get the syntax to alter a column.
*
* @param string $table The name of the database table to alter.
* @param \SimpleXMLElement $field The XML definition for the field.
*
* @return string
*
* @since 1.0
*/
protected function getChangeColumnSql($table, \SimpleXMLElement $field)
{
return 'ALTER TABLE ' . $this->db->quoteName($table) . ' CHANGE COLUMN ' . $this->db->quoteName((string) $field['Field']) . ' '
. $this->getColumnSQL($field);
}
/**
* Get the SQL syntax for a single column that would be included in a table create or alter statement.
*
* @param \SimpleXMLElement $field The XML field definition.
*
* @return string
*
* @since 1.0
*/
abstract protected function getColumnSql(\SimpleXMLElement $field);
/**
* Get the SQL syntax to drop a column.
*
* @param string $table The table name.
* @param string $name The name of the field to drop.
*
* @return string
*
* @since 1.0
*/
protected function getDropColumnSql($table, $name)
{
return 'ALTER TABLE ' . $this->db->quoteName($table) . ' DROP COLUMN ' . $this->db->quoteName($name);
}
/**
* Get the details list of keys for a table.
*
* @param array $keys An array of objects that comprise the keys for the table.
*
* @return array The lookup array. array({key name} => array(object, ...))
*
* @since 1.0
*/
protected function getKeyLookup($keys)
{
// First pass, create a lookup of the keys.
$lookup = [];
foreach ($keys as $key) {
if ($key instanceof \SimpleXMLElement) {
$kName = (string) $key['Key_name'];
} else {
$kName = $key->Key_name;
}
if (empty($lookup[$kName])) {
$lookup[$kName] = [];
}
$lookup[$kName][] = $key;
}
return $lookup;
}
/**
* Get the real name of the table, converting the prefix wildcard string if present.
*
* @param string $table The name of the table.
*
* @return string The real name of the table.
*
* @since 1.0
*/
protected function getRealTableName($table)
{
$prefix = $this->db->getPrefix();
// Replace the magic prefix if found.
$table = preg_replace('|^#__|', $prefix, $table);
return $table;
}
/**
* Import the data from the source into the existing tables.
*
* @return void
*
* @note Currently only supports XML format.
* @since 2.0.0
* @throws \RuntimeException on error.
*/
public function importData()
{
if ($this->from instanceof \SimpleXMLElement) {
$xml = $this->from;
} else {
$xml = new \SimpleXMLElement($this->from);
}
// Get all the table definitions.
$xmlTables = $xml->xpath('database/table_data');
foreach ($xmlTables as $table) {
// Convert the magic prefix into the real table name.
$tableName = $this->getRealTableName((string) $table['name']);
$rows = $table->children();
foreach ($rows as $row) {
if ($row->getName() == 'row') {
$entry = new \stdClass();
foreach ($row->children() as $data) {
if (isset($data['value_is_null'])) {
$entry->{(string) $data['name']} = null;
} else {
$entry->{(string) $data['name']} = (string) $data;
}
}
$this->db->insertObject($tableName, $entry);
}
}
}
}
/**
* Merges the incoming structure definition with the existing structure.
*
* @return void
*
* @note Currently only supports XML format.
* @since 1.0
* @throws \RuntimeException on error.
*/
public function mergeStructure()
{
$tables = $this->db->getTableList();
if ($this->from instanceof \SimpleXMLElement) {
$xml = $this->from;
} else {
$xml = new \SimpleXMLElement($this->from);
}
// Get all the table definitions.
$xmlTables = $xml->xpath('database/table_structure');
foreach ($xmlTables as $table) {
// Convert the magic prefix into the real table name.
$tableName = $this->getRealTableName((string) $table['name']);
if (\in_array($tableName, $tables, true)) {
// The table already exists. Now check if there is any difference.
if ($queries = $this->getAlterTableSql($table)) {
// Run the queries to upgrade the data structure.
foreach ($queries as $query) {
$this->db->setQuery((string) $query);
$this->db->execute();
}
}
} else {
// This is a new table.
$sql = $this->xmlToCreate($table);
$queries = explode(';', (string) $sql);
foreach ($queries as $query) {
if (!empty($query)) {
$this->db->setQuery((string) $query);
$this->db->execute();
}
}
}
}
}
/**
* Sets the database connector to use for exporting structure and/or data.
*
* @param DatabaseInterface $db The database connector.
*
* @return $this
*
* @since 1.0
*/
public function setDbo(DatabaseInterface $db)
{
$this->db = $db;
return $this;
}
/**
* Sets an internal option to merge the structure based on the input data.
*
* @param boolean $setting True to import the structure, false to not.
*
* @return $this
*
* @since 1.0
*/
public function withStructure($setting = true)
{
$this->options->withStructure = (bool) $setting;
return $this;
}
/**
* Get the SQL syntax to add a table.
*
* @param \SimpleXMLElement $table The table information.
*
* @return string
*
* @since 2.0.0
* @throws \RuntimeException
*/
abstract protected function xmlToCreate(\SimpleXMLElement $table);
}