gnu-social/lib/database/schemaupdater.php

138 lines
4.1 KiB
PHP

<?php
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social 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.
//
// GNU social 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 GNU social. If not, see <http://www.gnu.org/licenses/>.
/**
* Database schema utilities
*
* @category Database
* @package GNUsocial
* @author Evan Prodromou <evan@status.net>
* @copyright 2009 StatusNet, Inc.
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
defined('GNUSOCIAL') || die();
class SchemaUpdater
{
public function __construct($schema)
{
$this->schema = $schema;
$this->checksums = $this->getChecksums();
}
/**
* @param string $tableName
* @param array $tableDef
*/
public function register($tableName, array $tableDef)
{
// Check if the table we're registering is related to a Managed_DataObject
if (is_a(ucfirst($tableName), 'Managed_DataObject', true)) {
call_user_func("{$tableName}::beforeSchemaUpdate");
}
$this->tables[$tableName] = $tableDef;
}
/**
* Go ping em!
*
* @fixme handle tables that belong on different database servers...?
*/
public function checkSchema()
{
$checksums = $this->checksums;
foreach ($this->tables as $table => $def) {
$checksum = $this->checksum($def);
if (empty($checksums[$table])) {
common_log(LOG_DEBUG, "No previous schema_version for $table: updating to $checksum");
} elseif ($checksums[$table] === $checksum) {
common_log(LOG_DEBUG, "Last schema_version for $table up to date: $checksum");
continue;
} else {
common_log(LOG_DEBUG, "Last schema_version for $table is {$checksums[$table]}: updating to $checksum");
}
//$this->conn->query('START TRANSACTION');
$this->schema->ensureTable($table, $def);
$this->saveChecksum($table, $checksum);
//$this->conn->commit();
}
}
/**
* Calculate a checksum for this table definition array.
*
* @param array $def
* @return string
*/
public function checksum(array $def)
{
$flat = serialize($def);
return sha1($flat);
}
/**
* Pull all known table checksums into an array for easy lookup.
*
* @return array: associative array of table names to checksum strings
*/
protected function getChecksums()
{
$checksums = array();
try {
$sv = new Schema_version();
$sv->find();
while ($sv->fetch()) {
$checksums[$sv->table_name] = $sv->checksum;
}
return $checksums;
} catch (Exception $e) {
// no dice!
common_log(LOG_DEBUG, "Possibly schema_version table doesn't exist yet.");
}
return $checksums;
}
/**
* Save or update current available checksums.
*
* @param string $table
* @param string $checksum
*/
protected function saveChecksum($table, $checksum)
{
try {
$sv = new Schema_version();
$sv->table_name = $table;
$sv->checksum = $checksum;
$sv->modified = common_sql_now();
if (isset($this->checksums[$table])) {
$sv->update();
} else {
$sv->insert();
}
} catch (Exception $e) {
// no dice!
common_log(LOG_DEBUG, "Possibly schema_version table doesn't exist yet.");
}
$this->checksums[$table] = $checksum;
}
}