src/Core/StorageManager.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2021, the Friendica project
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Core;
  23
  24 use Exception;
  25 use Friendica\Core\Config\IConfig;
  26 use Friendica\Database\Database;
  27 use Friendica\Model\Storage;
  28 use Psr\Log\LoggerInterface;
  29
  30
  31 /**
  32  * Manage storage backends
  33  *
  34  * Core code uses this class to get and set current storage backend class.
  35  * Addons use this class to register and unregister additional backends.
  36  */
  37 class StorageManager
  38 {
  39         // Default tables to look for data
  40         const TABLES = ['photo', 'attach'];
  41
  42         // Default storage backends
  43         const DEFAULT_BACKENDS = [
  44                 Storage\Filesystem::NAME => Storage\Filesystem::class,
  45                 Storage\Database::NAME   => Storage\Database::class,
  46         ];
  47
  48         private $backends = [];
  49
  50         /**
  51          * @var Storage\IStorage[] A local cache for storage instances
  52          */
  53         private $backendInstances = [];
  54
  55         /** @var Database */
  56         private $dba;
  57         /** @var IConfig */
  58         private $config;
  59         /** @var LoggerInterface */
  60         private $logger;
  61         /** @var L10n */
  62         private $l10n;
  63
  64         /** @var Storage\IStorage */
  65         private $currentBackend;
  66
  67         /**
  68          * @param Database        $dba
  69          * @param IConfig         $config
  70          * @param LoggerInterface $logger
  71          * @param L10n            $l10n
  72          */
  73         public function __construct(Database $dba, IConfig $config, LoggerInterface $logger, L10n $l10n)
  74         {
  75                 $this->dba      = $dba;
  76                 $this->config   = $config;
  77                 $this->logger   = $logger;
  78                 $this->l10n     = $l10n;
  79                 $this->backends = $config->get('storage', 'backends', self::DEFAULT_BACKENDS);
  80
  81                 $currentName = $this->config->get('storage', 'name', '');
  82
  83                 // you can only use user backends as a "default" backend, so the second parameter is true
  84                 $this->currentBackend = $this->getByName($currentName, true);
  85         }
  86
  87         /**
  88          * Return current storage backend class
  89          *
  90          * @return Storage\IStorage|null
  91          */
  92         public function getBackend()
  93         {
  94                 return $this->currentBackend;
  95         }
  96
  97         /**
  98          * Return storage backend class by registered name
  99          *
 100          * @param string|null $name            Backend name
 101          * @param boolean     $onlyUserBackend True, if just user specific instances should be returrned (e.g. not SystemResource)
 102          *
 103          * @return Storage\IStorage|null null if no backend registered at $name
 104          *
 105          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 106          */
 107         public function getByName(string $name = null, $onlyUserBackend = false)
 108         {
 109                 // @todo 2020.09 Remove this call after 2 releases
 110                 $name = $this->checkLegacyBackend($name);
 111
 112                 // If there's no cached instance create a new instance
 113                 if (!isset($this->backendInstances[$name])) {
 114                         // If the current name isn't a valid backend (or the SystemResource instance) create it
 115                         if ($this->isValidBackend($name, $onlyUserBackend)) {
 116                                 switch ($name) {
 117                                         // Try the filesystem backend
 118                                         case Storage\Filesystem::getName():
 119                                                 $this->backendInstances[$name] = new Storage\Filesystem($this->config, $this->logger, $this->l10n);
 120                                                 break;
 121                                         // try the database backend
 122                                         case Storage\Database::getName():
 123                                                 $this->backendInstances[$name] = new Storage\Database($this->dba, $this->logger, $this->l10n);
 124                                                 break;
 125                                         // at least, try if there's an addon for the backend
 126                                         case Storage\SystemResource::getName():
 127                                                 $this->backendInstances[$name] = new Storage\SystemResource();
 128                                                 break;
 129                                         default:
 130                                                 $data = [
 131                                                         'name'    => $name,
 132                                                         'storage' => null,
 133                                                 ];
 134                                                 Hook::callAll('storage_instance', $data);
 135                                                 if (($data['storage'] ?? null) instanceof Storage\IStorage) {
 136                                                         $this->backendInstances[$data['name'] ?? $name] = $data['storage'];
 137                                                 } else {
 138                                                         return null;
 139                                                 }
 140                                                 break;
 141                                 }
 142                         } else {
 143                                 return null;
 144                         }
 145                 }
 146
 147                 return $this->backendInstances[$name];
 148         }
 149
 150         /**
 151          * Checks, if the storage is a valid backend
 152          *
 153          * @param string|null $name            The name or class of the backend
 154          * @param boolean     $onlyUserBackend True, if just user backend should get returned (e.g. not SystemResource)
 155          *
 156          * @return boolean True, if the backend is a valid backend
 157          */
 158         public function isValidBackend(string $name = null, bool $onlyUserBackend = false)
 159         {
 160                 return array_key_exists($name, $this->backends) ||
 161                        (!$onlyUserBackend && $name === Storage\SystemResource::getName());
 162         }
 163
 164         /**
 165          * Check for legacy backend storage class names (= full model class name)
 166          *
 167          * @todo 2020.09 Remove this function after 2 releases, because there shouldn't be any legacy backend classes left
 168          *
 169          * @param string|null $name a potential, legacy storage name ("Friendica\Model\Storage\...")
 170          *
 171          * @return string|null The current storage name
 172          */
 173         private function checkLegacyBackend(string $name = null)
 174         {
 175                 if (stristr($name, 'Friendica\Model\Storage\\')) {
 176                         $this->logger->notice('Using deprecated storage class value', ['name' => $name]);
 177                         return substr($name, 24);
 178                 }
 179
 180                 return $name;
 181         }
 182
 183         /**
 184          * Set current storage backend class
 185          *
 186          * @param string $name Backend class name
 187          *
 188          * @return boolean True, if the set was successful
 189          */
 190         public function setBackend(string $name = null)
 191         {
 192                 if (!$this->isValidBackend($name, false)) {
 193                         return false;
 194                 }
 195
 196                 if ($this->config->set('storage', 'name', $name)) {
 197                         $this->currentBackend = $this->getByName($name, false);
 198                         return true;
 199                 } else {
 200                         return false;
 201                 }
 202         }
 203
 204         /**
 205          * Get registered backends
 206          *
 207          * @return array
 208          */
 209         public function listBackends()
 210         {
 211                 return $this->backends;
 212         }
 213
 214         /**
 215          * Register a storage backend class
 216          *
 217          * You have to register the hook "storage_instance" as well to make this class work!
 218          *
 219          * @param string $class Backend class name
 220          *
 221          * @return boolean True, if the registration was successful
 222          */
 223         public function register(string $class)
 224         {
 225                 if (is_subclass_of($class, Storage\IStorage::class)) {
 226                         /** @var Storage\IStorage $class */
 227
 228                         $backends                    = $this->backends;
 229                         $backends[$class::getName()] = $class;
 230
 231                         if ($this->config->set('storage', 'backends', $backends)) {
 232                                 $this->backends = $backends;
 233                                 return true;
 234                         } else {
 235                                 return false;
 236                         }
 237                 } else {
 238                         return false;
 239                 }
 240         }
 241
 242         /**
 243          * Unregister a storage backend class
 244          *
 245          * @param string $class Backend class name
 246          *
 247          * @return boolean True, if unregistering was successful
 248          */
 249         public function unregister(string $class)
 250         {
 251                 if (is_subclass_of($class, Storage\IStorage::class)) {
 252                         /** @var Storage\IStorage $class */
 253
 254                         unset($this->backends[$class::getName()]);
 255
 256                         if ($this->currentBackend instanceof $class) {
 257                                 $this->config->set('storage', 'name', null);
 258                                 $this->currentBackend = null;
 259                         }
 260
 261                         return $this->config->set('storage', 'backends', $this->backends);
 262                 } else {
 263                         return false;
 264                 }
 265         }
 266
 267         /**
 268          * Move up to 5000 resources to storage $dest
 269          *
 270          * Copy existing data to destination storage and delete from source.
 271          * This method cannot move to legacy in-table `data` field.
 272          *
 273          * @param Storage\IStorage $destination Destination storage class name
 274          * @param array            $tables      Tables to look in for resources. Optional, defaults to ['photo', 'attach']
 275          * @param int              $limit       Limit of the process batch size, defaults to 5000
 276          *
 277          * @return int Number of moved resources
 278          * @throws Storage\StorageException
 279          * @throws Exception
 280          */
 281         public function move(Storage\IStorage $destination, array $tables = self::TABLES, int $limit = 5000)
 282         {
 283                 if (!$this->isValidBackend($destination, true)) {
 284                         throw new Storage\StorageException(sprintf("Can't move to storage backend '%s'", $destination::getName()));
 285                 }
 286
 287                 $moved = 0;
 288                 foreach ($tables as $table) {
 289                         // Get the rows where backend class is not the destination backend class
 290                         $resources = $this->dba->select(
 291                                 $table,
 292                                 ['id', 'data', 'backend-class', 'backend-ref'],
 293                                 ['`backend-class` IS NULL or `backend-class` != ?', $destination::getName()],
 294                                 ['limit' => $limit]
 295                         );
 296
 297                         while ($resource = $this->dba->fetch($resources)) {
 298                                 $id        = $resource['id'];
 299                                 $data      = $resource['data'];
 300                                 $source    = $this->getByName($resource['backend-class']);
 301                                 $sourceRef = $resource['backend-ref'];
 302
 303                                 if (!empty($source)) {
 304                                         $this->logger->info('Get data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 305                                         $data = $source->get($sourceRef);
 306                                 }
 307
 308                                 $this->logger->info('Save data to new backend.', ['newBackend' => $destination::getName()]);
 309                                 $destinationRef = $destination->put($data);
 310                                 $this->logger->info('Saved data.', ['newReference' => $destinationRef]);
 311
 312                                 if ($destinationRef !== '') {
 313                                         $this->logger->info('update row');
 314                                         if ($this->dba->update($table, ['backend-class' => $destination::getName(), 'backend-ref' => $destinationRef, 'data' => ''], ['id' => $id])) {
 315                                                 if (!empty($source)) {
 316                                                         $this->logger->info('Delete data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 317                                                         $source->delete($sourceRef);
 318                                                 }
 319                                                 $moved++;
 320                                         }
 321                                 }
 322                         }
 323
 324                         $this->dba->close($resources);
 325                 }
 326
 327                 return $moved;
 328         }
 329 }