gnu-social/lib/schema.php
2009-09-23 09:17:01 -04:00

179 lines
4.0 KiB
PHP

<?php
/**
* Laconica, the distributed open-source microblogging tool
*
* Database schema utilities
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category Database
* @package Laconica
* @author Evan Prodromou <evan@controlyourself.ca>
* @copyright 2009 Control Yourself, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://laconi.ca/
*/
if (!defined('LACONICA')) {
exit(1);
}
/**
* Class representing the database schema
*
* A class representing the database schema. Can be used to
* manipulate the schema -- especially for plugins and upgrade
* utilities.
*
* @category Database
* @package Laconica
* @author Evan Prodromou <evan@controlyourself.ca>
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://laconi.ca/
*/
class Schema
{
static $_single = null;
protected $conn = null;
protected function __construct()
{
// XXX: there should be an easier way to do this.
$user = new User();
$this->conn = $user->getDatabaseConnection();
$user->free();
unset($user);
}
static function get()
{
if (empty(self::$_single)) {
self::$_single = new Schema();
}
return self::$_single;
}
public function getTableDef($name)
{
$res =& $this->conn->query('DESCRIBE ' . $name);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
$td = new TableDef();
$td->name = $name;
$td->columns = array();
$row = array();
while ($res->fetchInto($row, DB_FETCHMODE_ASSOC)) {
$cd = new ColumnDef();
$cd->name = $row['Field'];
$packed = $row['Type'];
if (preg_match('/^(\w+)\((\d+)\)$/', $packed, $match)) {
$cd->type = $match[1];
$cd->size = $match[2];
} else {
$cd->type = $packed;
}
$cd->nullable = ($row['Null'] == 'YES') ? true : false;
$cd->key = $row['Key'];
$cd->default = $row['Default'];
$cd->extra = $row['Extra'];
$td->columns[] = $cd;
}
return $td;
}
public function getColumnDef($table, $column)
{
}
public function getIndexDef($table, $index)
{
}
public function createTable($name, $columns, $indices=null)
{
}
public function dropTable($name)
{
}
public function createIndex($name, $table, $columns)
{
}
public function dropIndex($name, $table)
{
}
public function addColumn($table, $columndef)
{
}
public function modifyColumn($table, $column, $columndef)
{
}
public function dropColumn($table, $column)
{
}
public function ensureTable($name, $columns, $indices)
{
$def = $this->tableDef($name);
if (empty($def)) {
return $this->createTable($name, $columns, $indices);
}
}
}
class TableDef
{
public $name;
public $columns;
}
class ColumnDef
{
public $name;
public $type;
public $size;
public $nullable;
public $key;
public $default;
public $extra;
}
class IndexDef
{
public $name;
public $table;
public $columns;
}