srchub/pluf/src/Pluf/Migration.php
2013-07-20 17:41:56 -05:00

362 lines
10 KiB
PHP

<?php
/* -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
# ***** BEGIN LICENSE BLOCK *****
# This file is part of Plume Framework, a simple PHP Application Framework.
# Copyright (C) 2001-2007 Loic d'Anterroches and contributors.
#
# Plume Framework is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# Plume Framework 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 Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# ***** END LICENSE BLOCK ***** */
/**
* A class to manage the migration of the code from one version to
* another, upward or downward.
*
* You can directly use the migrate.php script.
*
* Simple example usage:
*
* <pre>
* $m = new Pluf_Migration('MyApp');
* $m->migrate();
*
* // Install the application MyApp
* $m = new Pluf_Migration('MyApp');
* $m->install();
* // Uninstall the application MyApp
* $m->unInstall();
*
* $m = new Pluf_Migration();
* $m->migrate(); // migrate all the installed app to the newest version.
*
* $m = new Pluf_Migration();
* $m->migrate(3); // migrate (upgrade or downgrade) to version 3
* </pre>
*
*/
class Pluf_Migration
{
protected $app = ''; /**< Application beeing migrated. */
public $apps = array(); /**< Applications which are going to be migrated. */
public $to_version = null; /**< Target version for the migration. */
public $dry_run = false; /**< Set to true to not act. */
public $display = false; /**< Display on the console what is done. */
/**
* Create a new migration.
*
* @param mixed Application or array of applications to migrate.
*/
public function __construct($app=null)
{
if (!is_null($app)) {
if (is_array($app)) {
$this->apps = $app;
} else {
$this->apps = array($app);
}
} else {
$this->apps = Pluf::f('installed_apps');
}
}
/**
* Install the application.
*
* Basically run the base install function for each application
* and then set the version to the latest migration.
*/
public function install()
{
foreach ($this->apps as $app) {
$this->installApp($app);
}
return true;
}
/**
* Uninstall the application.
*/
public function unInstall()
{
$apps = array_reverse($this->apps);
foreach ($apps as $app) {
$this->installApp($app, true);
}
}
/**
* Backup the application.
*
* @param string Path to the backup folder
* @param string Backup name (null)
*/
public function backup($path, $name=null)
{
foreach ($this->apps as $app) {
$func = $app.'_Migrations_Backup_run';
Pluf::loadFunction($func);
if ($this->display) {
echo($func."\n");
}
if (!$this->dry_run) {
$ret = $func($path, $name);
}
}
return true;
}
/**
* Restore the application.
*
* @param string Path to the backup folder
* @param string Backup name
*/
public function restore($path, $name)
{
foreach ($this->apps as $app) {
$func = $app.'_Migrations_Backup_restore';
Pluf::loadFunction($func);
if ($this->display) {
echo($func."\n");
}
if (!$this->dry_run) {
$ret = $func($path, $name);
}
}
return true;
}
/**
* Run the migration.
*
*/
public function migrate($to_version=null)
{
$this->to_version = $to_version;
foreach ($this->apps as $app) {
$this->app = $app;
$migrations = $this->findMigrations();
// The run will throw an exception in case of error.
$this->runMigrations($migrations);
}
return true;
}
/**
* Un/Install the given application.
*
* @param string Application to install.
* @param bool Uninstall (false)
*/
public function installApp($app, $uninstall=false)
{
if ($uninstall) {
$func = $app.'_Migrations_Install_teardown';
} else {
$func = $app.'_Migrations_Install_setup';
}
$ret = true;
Pluf::loadFunction($func);
if ($this->display) {
echo($func."\n");
}
if (!$this->dry_run) {
$ret = $func(); // Run the install/uninstall
if (!$uninstall) {
//
$this->app = $app;
$migrations = $this->findMigrations();
if (count($migrations) > 0) {
$to_version = max(array_keys($migrations));
} else {
$to_version = 0;
}
$this->setAppVersion($app, $to_version);
} else {
if ($app != 'Pluf') {
// If Pluf we do not have the schema info table
// anymore
$this->delAppInfo($app);
}
}
}
return $ret;
}
/**
* Find the migrations for the current app.
*
* @return array Migrations names indexed by order.
*/
public function findMigrations()
{
$migrations = array();
if (false !== ($mdir = Pluf::fileExists($this->app.'/Migrations'))) {
$dir = new DirectoryIterator($mdir);
foreach($dir as $file) {
$matches = array();
if (!$file->isDot() && !$file->isDir()
&& preg_match('#^(\d+)#', $file->getFilename(), $matches)) {
$info = pathinfo($file->getFilename());
$migrations[(int)$matches[1]] = $info['filename'];
}
}
}
return $migrations;
}
/**
* Run the migrations.
*
* From an array of possible migrations, it will first get the
* current version of the app and then based on $this->to_version
* will run the migrations in the right order or do nothing if
* nothing to be done.
*
* @param array Possible migrations.
*/
public function runMigrations($migrations)
{
if (empty($migrations)) {
return;
}
$current = $this->getAppVersion($this->app);
if ($this->to_version === null) {
$to_version = max(array_keys($migrations));
} else {
$to_version = $this->to_version;
}
if ($to_version == $current) {
return; // Nothing to do
}
$the_way = 'up'; // Tribute to Pat Metheny
if ($to_version > $current) {
// upgrade
$min = $current + 1;
$max = $to_version;
} else {
// downgrade
$the_way = 'do';
$max = $current;
$min = $to_version + 1;
}
// Filter the migrations
$to_run = array();
foreach ($migrations as $order=>$name) {
if ($order < $min or $order > $max) {
continue;
}
if ($the_way == 'up') {
$to_run[] = array($order, $name);
} else {
array_unshift($to_run, array($order, $name));
}
}
asort($to_run);
// Run the migrations
foreach ($to_run as $migration) {
$this->runMigration($migration, $the_way);
}
}
/**
* Run the given migration.
*/
public function runMigration($migration, $the_way='up')
{
$target_version = ($the_way == 'up') ? $migration[0] : $migration[0]-1;
if ($this->display) {
echo($migration[0].' '.$migration[1].' '.$the_way."\n");
}
if (!$this->dry_run) {
if ($the_way == 'up') {
$func = $this->app.'_Migrations_'.$migration[1].'_up';
} else {
$func = $this->app.'_Migrations_'.$migration[1].'_down';
}
Pluf::loadFunction($func);
$func(); // Real migration run
$this->setAppVersion($this->app, $target_version);
}
}
/**
* Set the application version.
*
* @param string Application
* @param int Version
* @return true
*/
public function setAppVersion($app, $version)
{
$gschema = new Pluf_DB_SchemaInfo();
$sql = new Pluf_SQL('application=%s', $app);
$appinfo = $gschema->getList(array('filter' => $sql->gen()));
if ($appinfo->count() == 1) {
$appinfo[0]->version = $version;
$appinfo[0]->update();
} else {
$schema = new Pluf_DB_SchemaInfo();
$schema->application = $app;
$schema->version = $version;
$schema->create();
}
return true;
}
/**
* Remove the application information.
*
* @param string Application
* @return true
*/
public function delAppInfo($app)
{
$gschema = new Pluf_DB_SchemaInfo();
$sql = new Pluf_SQL('application=%s', $app);
$appinfo = $gschema->getList(array('filter' => $sql->gen()));
if ($appinfo->count() == 1) {
$appinfo[0]->delete();
}
return true;
}
/**
* Get the current version of the app.
*
* @param string Application.
* @return int Version.
*/
public function getAppVersion($app)
{
try {
$db =& Pluf::db();
$res = $db->select('SELECT version FROM '.$db->pfx.'schema_info WHERE application='.$db->esc($app));
return (int) $res[0]['version'];
} catch (Exception $e) {
// We should not be here, only in the case of nothing
// installed. I am not sure if this is a good way to
// handle this border case anyway. Maybe better to have an
// 'install' method to run all the migrations in order.
return 0;
}
}
}