server/apps/files_versions/lib/versions.php
2013-10-11 17:00:21 +02:00

559 lines
18 KiB
PHP

<?php
/**
* Copyright (c) 2012 Frank Karlitschek <frank@owncloud.org>
* 2013 Bjoern Schiessle <schiessle@owncloud.com>
* This file is licensed under the Affero General Public License version 3 or
* later.
* See the COPYING-README file.
*/
/**
* Versions
*
* A class to handle the versioning of files.
*/
namespace OCA\Files_Versions;
class Storage {
const DEFAULTENABLED=true;
const DEFAULTMAXSIZE=50; // unit: percentage; 50% of available disk space/quota
const VERSIONS_ROOT = 'files_versions/';
private static $max_versions_per_interval = array(
//first 10sec, one version every 2sec
1 => array('intervalEndsAfter' => 10, 'step' => 2),
//next minute, one version every 10sec
2 => array('intervalEndsAfter' => 60, 'step' => 10),
//next hour, one version every minute
3 => array('intervalEndsAfter' => 3600, 'step' => 60),
//next 24h, one version every hour
4 => array('intervalEndsAfter' => 86400, 'step' => 3600),
//next 30days, one version per day
5 => array('intervalEndsAfter' => 2592000, 'step' => 86400),
//until the end one version per week
6 => array('intervalEndsAfter' => -1, 'step' => 604800),
);
public static function getUidAndFilename($filename) {
$uid = \OC\Files\Filesystem::getOwner($filename);
\OC\Files\Filesystem::initMountPoints($uid);
if ( $uid != \OCP\User::getUser() ) {
$info = \OC\Files\Filesystem::getFileInfo($filename);
$ownerView = new \OC\Files\View('/'.$uid.'/files');
$filename = $ownerView->getPath($info['fileid']);
}
return array($uid, $filename);
}
/**
* get current size of all versions from a given user
*
* @param $user user who owns the versions
* @return mixed versions size or false if no versions size is stored
*/
private static function getVersionsSize($user) {
$query = \OC_DB::prepare('SELECT `size` FROM `*PREFIX*files_versions` WHERE `user`=?');
$result = $query->execute(array($user))->fetchAll();
if ($result) {
return $result[0]['size'];
}
return false;
}
/**
* write to the database how much space is in use for versions
*
* @param $user owner of the versions
* @param $size size of the versions
*/
private static function setVersionsSize($user, $size) {
if ( self::getVersionsSize($user) === false) {
$query = \OC_DB::prepare('INSERT INTO `*PREFIX*files_versions` (`size`, `user`) VALUES (?, ?)');
}else {
$query = \OC_DB::prepare('UPDATE `*PREFIX*files_versions` SET `size`=? WHERE `user`=?');
}
$query->execute(array($size, $user));
}
/**
* store a new version of a file.
*/
public static function store($filename) {
if(\OCP\Config::getSystemValue('files_versions', Storage::DEFAULTENABLED)=='true') {
// if the file gets streamed we need to remove the .part extension
// to get the right target
$ext = pathinfo($filename, PATHINFO_EXTENSION);
if ($ext === 'part') {
$filename = substr($filename, 0, strlen($filename)-5);
}
list($uid, $filename) = self::getUidAndFilename($filename);
$files_view = new \OC\Files\View('/'.$uid .'/files');
$users_view = new \OC\Files\View('/'.$uid);
$versions_view = new \OC\Files\View('/'.$uid.'/files_versions');
// check if filename is a directory
if($files_view->is_dir($filename)) {
return false;
}
// we should have a source file to work with, and the file shouldn't
// be empty
$fileExists = $files_view->file_exists($filename);
if (!($fileExists && $files_view->filesize($filename) > 0)) {
return false;
}
// create all parent folders
self::createMissingDirectories($filename, $users_view);
$versionsSize = self::getVersionsSize($uid);
if ( $versionsSize === false || $versionsSize < 0 ) {
$versionsSize = self::calculateSize($uid);
}
// assumption: we need filesize($filename) for the new version +
// some more free space for the modified file which might be
// 1.5 times as large as the current version -> 2.5
$neededSpace = $files_view->filesize($filename) * 2.5;
$versionsSize = self::expire($filename, $versionsSize, $neededSpace);
// disable proxy to prevent multiple fopen calls
$proxyStatus = \OC_FileProxy::$enabled;
\OC_FileProxy::$enabled = false;
// store a new version of a file
$users_view->copy('files'.$filename, 'files_versions'.$filename.'.v'.$users_view->filemtime('files'.$filename));
// reset proxy state
\OC_FileProxy::$enabled = $proxyStatus;
$versionsSize += $users_view->filesize('files'.$filename);
self::setVersionsSize($uid, $versionsSize);
}
}
/**
* Delete versions of a file
*/
public static function delete($filename) {
list($uid, $filename) = self::getUidAndFilename($filename);
$versions_fileview = new \OC\Files\View('/'.$uid .'/files_versions');
$abs_path = $versions_fileview->getLocalFile($filename.'.v');
if( ($versions = self::getVersions($uid, $filename)) ) {
$versionsSize = self::getVersionsSize($uid);
if ( $versionsSize === false || $versionsSize < 0 ) {
$versionsSize = self::calculateSize($uid);
}
foreach ($versions as $v) {
unlink($abs_path . $v['version']);
$versionsSize -= $v['size'];
}
self::setVersionsSize($uid, $versionsSize);
}
}
/**
* rename versions of a file
*/
public static function rename($old_path, $new_path) {
list($uid, $oldpath) = self::getUidAndFilename($old_path);
list($uidn, $newpath) = self::getUidAndFilename($new_path);
$versions_view = new \OC\Files\View('/'.$uid .'/files_versions');
$files_view = new \OC\Files\View('/'.$uid .'/files');
// if the file already exists than it was a upload of a existing file
// over the web interface -> store() is the right function we need here
if ($files_view->file_exists($newpath)) {
return self::store($new_path);
}
self::expire($newpath);
if ( $files_view->is_dir($oldpath) && $versions_view->is_dir($oldpath) ) {
$versions_view->rename($oldpath, $newpath);
} else if ( ($versions = Storage::getVersions($uid, $oldpath)) ) {
// create missing dirs if necessary
self::createMissingDirectories($newpath, new \OC\Files\View('/'. $uidn));
foreach ($versions as $v) {
$versions_view->rename($oldpath.'.v'.$v['version'], $newpath.'.v'.$v['version']);
}
}
}
/**
* rollback to an old version of a file.
*/
public static function rollback($file, $revision) {
if(\OCP\Config::getSystemValue('files_versions', Storage::DEFAULTENABLED)=='true') {
list($uid, $filename) = self::getUidAndFilename($file);
$users_view = new \OC\Files\View('/'.$uid);
$files_view = new \OC\Files\View('/'.\OCP\User::getUser().'/files');
$versionCreated = false;
//first create a new version
$version = 'files_versions'.$filename.'.v'.$users_view->filemtime('files'.$filename);
if ( !$users_view->file_exists($version)) {
// disable proxy to prevent multiple fopen calls
$proxyStatus = \OC_FileProxy::$enabled;
\OC_FileProxy::$enabled = false;
$users_view->copy('files'.$filename, 'files_versions'.$filename.'.v'.$users_view->filemtime('files'.$filename));
// reset proxy state
\OC_FileProxy::$enabled = $proxyStatus;
$versionCreated = true;
}
// rollback
if( @$users_view->rename('files_versions'.$filename.'.v'.$revision, 'files'.$filename) ) {
$files_view->touch($file, $revision);
Storage::expire($file);
return true;
}else if ( $versionCreated ) {
$users_view->unlink($version);
}
}
return false;
}
/**
* @brief get a list of all available versions of a file in descending chronological order
* @param $uid user id from the owner of the file
* @param $filename file to find versions of, relative to the user files dir
* @returns array
*/
public static function getVersions($uid, $filename) {
$versions = array();
// fetch for old versions
$view = new \OC\Files\View('/' . $uid . '/' . self::VERSIONS_ROOT);
$pathinfo = pathinfo($filename);
$files = $view->getDirectoryContent($pathinfo['dirname']);
$versionedFile = $pathinfo['basename'];
foreach ($files as $file) {
if ($file['type'] === 'file') {
$pos = strrpos($file['path'], '.v');
$currentFile = substr($file['name'], 0, strrpos($file['name'], '.v'));
if ($currentFile === $versionedFile) {
$version = substr($file['path'], $pos + 2);
$key = $version . '#' . $filename;
$versions[$key]['cur'] = 0;
$versions[$key]['version'] = $version;
$versions[$key]['humanReadableTimestamp'] = self::getHumanReadableTimestamp($version);
$versions[$key]['preview'] = \OCP\Util::linkToRoute('core_ajax_versions_preview', array('file' => $filename, 'version' => $version, 'user' => $uid));
$versions[$key]['path'] = $filename;
$versions[$key]['size'] = $file['size'];
}
}
}
// sort with newest version first
krsort($versions);
return $versions;
}
/**
* @brief translate a timestamp into a string like "5 days ago"
* @param int $timestamp
* @return string for example "5 days ago"
*/
private static function getHumanReadableTimestamp($timestamp) {
$diff = time() - $timestamp;
if ($diff < 60) { // first minute
return $diff . " seconds ago";
} elseif ($diff < 3600) { //first hour
return round($diff / 60) . " minutes ago";
} elseif ($diff < 86400) { // first day
return round($diff / 3600) . " hours ago";
} elseif ($diff < 604800) { //first week
return round($diff / 86400) . " days ago";
} elseif ($diff < 2419200) { //first month
return round($diff / 604800) . " weeks ago";
} elseif ($diff < 29030400) { // first year
return round($diff / 2419200) . " months ago";
} else {
return round($diff / 29030400) . " years ago";
}
}
/**
* @brief deletes used space for files versions in db if user was deleted
*
* @param type $uid id of deleted user
* @return result of db delete operation
*/
public static function deleteUser($uid) {
$query = \OC_DB::prepare('DELETE FROM `*PREFIX*files_versions` WHERE `user`=?');
return $query->execute(array($uid));
}
/**
* @brief get the size of all stored versions from a given user
* @param $uid id from the user
* @return size of vesions
*/
private static function calculateSize($uid) {
if( \OCP\Config::getSystemValue('files_versions', Storage::DEFAULTENABLED)=='true' ) {
$versions_fileview = new \OC\Files\View('/'.$uid.'/files_versions');
$versionsRoot = $versions_fileview->getLocalFolder('');
$iterator = new \RecursiveIteratorIterator(
new \RecursiveDirectoryIterator($versionsRoot),
\RecursiveIteratorIterator::CHILD_FIRST
);
$size = 0;
foreach ($iterator as $path) {
if ( preg_match('/^.+\.v(\d+)$/', $path, $match) ) {
$relpath = substr($path, strlen($versionsRoot)-1);
$size += $versions_fileview->filesize($relpath);
}
}
return $size;
}
}
/**
* @brief returns all stored file versions from a given user
* @param $uid id to the user
* @return array with contains two arrays 'all' which contains all versions sorted by age and 'by_file' which contains all versions sorted by filename
*/
private static function getAllVersions($uid) {
$view = new \OC\Files\View('/' . $uid . '/');
$dirs = array(self::VERSIONS_ROOT);
while (!empty($dirs)) {
$dir = array_pop($dirs);
$files = $view->getDirectoryContent($dir);
foreach ($files as $file) {
if ($file['type'] === 'dir') {
array_push($dirs, $file['path']);
} else {
$versionsBegin = strrpos($file['path'], '.v');
$relPathStart = strlen(self::VERSIONS_ROOT);
$version = substr($file['path'], $versionsBegin + 2);
$relpath = substr($file['path'], $relPathStart, $versionsBegin - $relPathStart);
$key = $version . '#' . $relpath;
$versions[$key] = array('path' => $relpath, 'timestamp' => $version);
}
}
}
ksort($versions);
$result = array();
foreach ($versions as $key => $value) {
$size = $view->filesize($value['path']);
$filename = $value['path'];
$result['all'][$key]['version'] = $value['timestamp'];
$result['all'][$key]['path'] = $filename;
$result['all'][$key]['size'] = $size;
$result['by_file'][$filename][$key]['version'] = $value['timestamp'];
$result['by_file'][$filename][$key]['path'] = $filename;
$result['by_file'][$filename][$key]['size'] = $size;
}
return $result;
}
/**
* @brief Erase a file's versions which exceed the set quota
*/
private static function expire($filename, $versionsSize = null, $offset = 0) {
if(\OCP\Config::getSystemValue('files_versions', Storage::DEFAULTENABLED)=='true') {
list($uid, $filename) = self::getUidAndFilename($filename);
$versionsFileview = new \OC\Files\View('/'.$uid.'/files_versions');
// get available disk space for user
$softQuota = true;
$quota = \OC_Preferences::getValue($uid, 'files', 'quota');
if ( $quota === null || $quota === 'default') {
$quota = \OC_Appconfig::getValue('files', 'default_quota');
}
if ( $quota === null || $quota === 'none' ) {
$quota = \OC\Files\Filesystem::free_space('/');
$softQuota = false;
} else {
$quota = \OCP\Util::computerFileSize($quota);
}
// make sure that we have the current size of the version history
if ( $versionsSize === null ) {
$versionsSize = self::getVersionsSize($uid);
if ( $versionsSize === false || $versionsSize < 0 ) {
$versionsSize = self::calculateSize($uid);
}
}
// calculate available space for version history
// subtract size of files and current versions size from quota
if ($softQuota) {
$files_view = new \OC\Files\View('/'.$uid.'/files');
$rootInfo = $files_view->getFileInfo('/');
$free = $quota-$rootInfo['size']; // remaining free space for user
if ( $free > 0 ) {
$availableSpace = ($free * self::DEFAULTMAXSIZE / 100) - ($versionsSize + $offset); // how much space can be used for versions
} else {
$availableSpace = $free - $versionsSize - $offset;
}
} else {
$availableSpace = $quota - $offset;
}
// with the probability of 0.1% we reduce the number of all versions not only for the current file
$random = rand(0, 1000);
if ($random == 0) {
$allFiles = true;
} else {
$allFiles = false;
}
$allVersions = Storage::getVersions($uid, $filename);
$versionsByFile[$filename] = $allVersions;
$sizeOfDeletedVersions = self::delOldVersions($versionsByFile, $allVersions, $versionsFileview);
$availableSpace = $availableSpace + $sizeOfDeletedVersions;
$versionsSize = $versionsSize - $sizeOfDeletedVersions;
// if still not enough free space we rearrange the versions from all files
if ($availableSpace <= 0 || $allFiles) {
$result = Storage::getAllVersions($uid);
$versionsByFile = $result['by_file'];
$allVersions = $result['all'];
$sizeOfDeletedVersions = self::delOldVersions($versionsByFile, $allVersions, $versionsFileview);
$availableSpace = $availableSpace + $sizeOfDeletedVersions;
$versionsSize = $versionsSize - $sizeOfDeletedVersions;
}
// Check if enough space is available after versions are rearranged.
// If not we delete the oldest versions until we meet the size limit for versions,
// but always keep the two latest versions
$numOfVersions = count($allVersions) -2 ;
$i = 0;
while ($availableSpace < 0 && $i < $numOfVersions) {
$version = current($allVersions);
$versionsFileview->unlink($version['path'].'.v'.$version['version']);
$versionsSize -= $version['size'];
$availableSpace += $version['size'];
next($allVersions);
$i++;
}
return $versionsSize; // finally return the new size of the version history
}
return false;
}
/**
* @brief delete old version from a given list of versions
*
* @param array $versionsByFile list of versions ordered by files
* @param array $allVversions all versions accross multiple files
* @param $versionsFileview OC\Files\View on data/user/files_versions
* @return size of releted versions
*/
private static function delOldVersions($versionsByFile, &$allVersions, $versionsFileview) {
$time = time();
$size = 0;
// delete old versions for every given file
foreach ($versionsByFile as $versions) {
$versions = array_reverse($versions); // newest version first
$interval = 1;
$step = Storage::$max_versions_per_interval[$interval]['step'];
if (Storage::$max_versions_per_interval[$interval]['intervalEndsAfter'] == -1) {
$nextInterval = -1;
} else {
$nextInterval = $time - Storage::$max_versions_per_interval[$interval]['intervalEndsAfter'];
}
$firstVersion = reset($versions);
$firstKey = key($versions);
$prevTimestamp = $firstVersion['version'];
$nextVersion = $firstVersion['version'] - $step;
unset($versions[$firstKey]);
foreach ($versions as $key => $version) {
$newInterval = true;
while ($newInterval) {
if ($nextInterval == -1 || $version['version'] >= $nextInterval) {
if ($version['version'] > $nextVersion) {
//distance between two version too small, delete version
$versionsFileview->unlink($version['path'] . '.v' . $version['version']);
$size += $version['size'];
unset($allVersions[$key]); // update array with all versions
} else {
$nextVersion = $version['version'] - $step;
}
$newInterval = false; // version checked so we can move to the next one
} else { // time to move on to the next interval
$interval++;
$step = Storage::$max_versions_per_interval[$interval]['step'];
$nextVersion = $prevTimestamp - $step;
if (Storage::$max_versions_per_interval[$interval]['intervalEndsAfter'] == -1) {
$nextInterval = -1;
} else {
$nextInterval = $time - Storage::$max_versions_per_interval[$interval]['intervalEndsAfter'];
}
$newInterval = true; // we changed the interval -> check same version with new interval
}
}
$prevTimestamp = $version['version'];
}
}
return $size;
}
/**
* @brief create recursively missing directories
* @param string $filename $path to a file
* @param \OC\Files\View $view view on data/user/
*/
private static function createMissingDirectories($filename, $view) {
$dirname = \OC_Filesystem::normalizePath(dirname($filename));
$dirParts = explode('/', $dirname);
$dir = "/files_versions";
foreach ($dirParts as $part) {
$dir = $dir . '/' . $part;
if (!$view->file_exists($dir)) {
$view->mkdir($dir);
}
}
}
}