gnu-social/lib/schema.php
Evan Prodromou 544c58d263 Some bug fixes
The $tomod variable wasn't set, and the ColumnDef constructor
didn't work without any args. These are fixed.
2009-10-01 15:43:08 -04:00

446 lines
11 KiB
PHP

<?php
/**
* StatusNet, 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 StatusNet
* @author Evan Prodromou <evan@status.net>
* @copyright 2009 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
if (!defined('STATUSNET')) {
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 StatusNet
* @author Evan Prodromou <evan@status.net>
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
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)
{
$td = $this->getTableDef($table);
foreach ($td->columns as $cd) {
if ($cd->name == $column) {
return $cd;
}
}
return null;
}
public function getIndexDef($table, $index)
{
return null;
}
public function createTable($name, $columns, $indices=null)
{
$uniques = array();
$primary = array();
$indices = array();
$sql = "CREATE TABLE $name (\n";
for ($i = 0; $i < count($columns); $i++) {
$cd =& $columns[$i];
if ($i > 0) {
$sql .= ",\n";
}
$sql .= $this->_columnSql($cd);
switch ($cd->key) {
case 'UNI':
$uniques[] = $cd->name;
break;
case 'PRI':
$primary[] = $cd->name;
break;
case 'MUL':
$indices[] = $cd->name;
break;
}
}
if (count($primary) > 0) { // it really should be...
$sql .= ",\nconstraint primary key (" . implode(',', $primary) . ")";
}
foreach ($uniques as $u) {
$sql .= ",\nunique index {$name}_{$u}_idx ($u)";
}
foreach ($indices as $i) {
$sql .= ",\nindex {$name}_{$i}_idx ($i)";
}
$sql .= "); ";
common_debug($sql);
$res =& $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function dropTable($name)
{
$res =& $this->conn->query("DROP TABLE $name");
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function createIndex($table, $columnNames, $name = null)
{
if (!is_array($columnNames)) {
$columnNames = array($columnNames);
}
if (empty($name)) {
$name = "$table_".implode("_", $columnNames)."_idx";
}
$res =& $this->conn->query("ALTER TABLE $table ADD INDEX $name (".implode(",", $columnNames).")");
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function dropIndex($table, $name)
{
$res =& $this->conn->query("ALTER TABLE $table DROP INDEX $name");
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function addColumn($table, $columndef)
{
$sql = "ALTER TABLE $table ADD COLUMN " . $this->_columnSql($columndef);
$res =& $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function modifyColumn($table, $columndef)
{
$sql = "ALTER TABLE $table MODIFY COLUMN " . $this->_columnSql($columndef);
$res =& $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function dropColumn($table, $columnName)
{
$sql = "ALTER TABLE $table DROP COLUMN $columnName";
$res =& $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
public function ensureTable($tableName, $columns, $indices=null)
{
// XXX: DB engine portability -> toilet
try {
$td = $this->getTableDef($tableName);
} catch (Exception $e) {
if (preg_match('/no such table/', $e->getMessage())) {
return $this->createTable($tableName, $columns, $indices);
} else {
throw $e;
}
}
$cur = $this->_names($td->columns);
$new = $this->_names($columns);
$toadd = array_diff($new, $cur);
$todrop = array_diff($cur, $new);
$same = array_intersect($new, $cur);
$tomod = array();
foreach ($same as $m) {
$curCol = $this->_byName($td->columns, $m);
$newCol = $this->_byName($columns, $m);
if (!$newCol->equals($curCol)) {
$tomod[] = $newCol->name;
}
}
if (count($toadd) + count($todrop) + count($tomod) == 0) {
// nothing to do
return true;
}
// For efficiency, we want this all in one
// query, instead of using our methods.
$phrase = array();
foreach ($toadd as $columnName) {
$cd = $this->_byName($columns, $columnName);
$phrase[] = 'ADD COLUMN ' . $this->_columnSql($cd);
}
foreach ($todrop as $columnName) {
$phrase[] = 'DROP COLUMN ' . $columnName;
}
foreach ($tomod as $columnName) {
$cd = $this->_byName($columns, $columnName);
$phrase[] = 'MODIFY COLUMN ' . $this->_columnSql($cd);
}
$sql = 'ALTER TABLE ' . $tableName . ' ' . implode(', ', $phrase);
$res =& $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
function _names($cds)
{
$names = array();
foreach ($cds as $cd) {
$names[] = $cd->name;
}
return $names;
}
function _byName($cds, $name)
{
foreach ($cds as $cd) {
if ($cd->name == $name) {
return $cd;
}
}
return null;
}
function _columnSql($cd)
{
$sql = "{$cd->name} ";
if (!empty($cd->size)) {
$sql .= "{$cd->type}({$cd->size}) ";
} else {
$sql .= "{$cd->type} ";
}
if (!empty($cd->default)) {
$sql .= "default {$cd->default} ";
} else {
$sql .= ($cd->nullable) ? "null " : "not null ";
}
return $sql;
}
}
class TableDef
{
public $name;
public $columns;
}
class ColumnDef
{
public $name;
public $type;
public $size;
public $nullable;
public $key;
public $default;
public $extra;
function __construct($name=null, $type=null, $size=null,
$nullable=true, $key=null, $default=null,
$extra=null) {
$this->name = strtolower($name);
$this->type = strtolower($type);
$this->size = $size+0;
$this->nullable = $nullable;
$this->key = $key;
$this->default = $default;
$this->extra = $extra;
}
function equals($other)
{
return ($this->name == $other->name &&
$this->_typeMatch($other) &&
$this->_defaultMatch($other) &&
$this->_nullMatch($other) &&
$this->key == $other->key);
}
function _typeMatch($other)
{
switch ($this->type) {
case 'integer':
case 'int':
return ($other->type == 'integer' ||
$other->type == 'int');
break;
default:
return ($this->type == $other->type &&
$this->size == $other->size);
}
}
function _defaultMatch($other)
{
return ((is_null($this->default) && is_null($other->default)) ||
($this->default == $other->default));
}
function _nullMatch($other)
{
return ((!is_null($this->default) && !is_null($other->default) &&
$this->default == $other->default) ||
($this->nullable == $other->nullable));
}
}
class IndexDef
{
public $name;
public $table;
public $columns;
}