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                                         case Storage\ExternalResource::getName():
 130                                                 $this->backendInstances[$name] = new Storage\ExternalResource();
 131                                                 break;
 132                                         default:
 133                                                 $data = [
 134                                                         'name'    => $name,
 135                                                         'storage' => null,
 136                                                 ];
 137                                                 Hook::callAll('storage_instance', $data);
 138                                                 if (($data['storage'] ?? null) instanceof Storage\IStorage) {
 139                                                         $this->backendInstances[$data['name'] ?? $name] = $data['storage'];
 140                                                 } else {
 141                                                         return null;
 142                                                 }
 143                                                 break;
 144                                 }
 145                         } else {
 146                                 return null;
 147                         }
 148                 }
 149
 150                 return $this->backendInstances[$name];
 151         }
 152
 153         /**
 154          * Checks, if the storage is a valid backend
 155          *
 156          * @param string|null $name            The name or class of the backend
 157          * @param boolean     $onlyUserBackend True, if just user backend should get returned (e.g. not SystemResource)
 158          *
 159          * @return boolean True, if the backend is a valid backend
 160          */
 161         public function isValidBackend(string $name = null, bool $onlyUserBackend = false)
 162         {
 163                 return array_key_exists($name, $this->backends) ||
 164                        (!$onlyUserBackend && in_array($name, [Storage\SystemResource::getName(), Storage\ExternalResource::getName()]));
 165         }
 166
 167         /**
 168          * Check for legacy backend storage class names (= full model class name)
 169          *
 170          * @todo 2020.09 Remove this function after 2 releases, because there shouldn't be any legacy backend classes left
 171          *
 172          * @param string|null $name a potential, legacy storage name ("Friendica\Model\Storage\...")
 173          *
 174          * @return string|null The current storage name
 175          */
 176         private function checkLegacyBackend(string $name = null)
 177         {
 178                 if (stristr($name, 'Friendica\Model\Storage\\')) {
 179                         $this->logger->notice('Using deprecated storage class value', ['name' => $name]);
 180                         return substr($name, 24);
 181                 }
 182
 183                 return $name;
 184         }
 185
 186         /**
 187          * Set current storage backend class
 188          *
 189          * @param string $name Backend class name
 190          *
 191          * @return boolean True, if the set was successful
 192          */
 193         public function setBackend(string $name = null)
 194         {
 195                 if (!$this->isValidBackend($name, false)) {
 196                         return false;
 197                 }
 198
 199                 if ($this->config->set('storage', 'name', $name)) {
 200                         $this->currentBackend = $this->getByName($name, false);
 201                         return true;
 202                 } else {
 203                         return false;
 204                 }
 205         }
 206
 207         /**
 208          * Get registered backends
 209          *
 210          * @return array
 211          */
 212         public function listBackends()
 213         {
 214                 return $this->backends;
 215         }
 216
 217         /**
 218          * Register a storage backend class
 219          *
 220          * You have to register the hook "storage_instance" as well to make this class work!
 221          *
 222          * @param string $class Backend class name
 223          *
 224          * @return boolean True, if the registration was successful
 225          */
 226         public function register(string $class)
 227         {
 228                 if (is_subclass_of($class, Storage\IStorage::class)) {
 229                         /** @var Storage\IStorage $class */
 230
 231                         $backends                    = $this->backends;
 232                         $backends[$class::getName()] = $class;
 233
 234                         if ($this->config->set('storage', 'backends', $backends)) {
 235                                 $this->backends = $backends;
 236                                 return true;
 237                         } else {
 238                                 return false;
 239                         }
 240                 } else {
 241                         return false;
 242                 }
 243         }
 244
 245         /**
 246          * Unregister a storage backend class
 247          *
 248          * @param string $class Backend class name
 249          *
 250          * @return boolean True, if unregistering was successful
 251          */
 252         public function unregister(string $class)
 253         {
 254                 if (is_subclass_of($class, Storage\IStorage::class)) {
 255                         /** @var Storage\IStorage $class */
 256
 257                         unset($this->backends[$class::getName()]);
 258
 259                         if ($this->currentBackend instanceof $class) {
 260                                 $this->config->set('storage', 'name', null);
 261                                 $this->currentBackend = null;
 262                         }
 263
 264                         return $this->config->set('storage', 'backends', $this->backends);
 265                 } else {
 266                         return false;
 267                 }
 268         }
 269
 270         /**
 271          * Move up to 5000 resources to storage $dest
 272          *
 273          * Copy existing data to destination storage and delete from source.
 274          * This method cannot move to legacy in-table `data` field.
 275          *
 276          * @param Storage\IStorage $destination Destination storage class name
 277          * @param array            $tables      Tables to look in for resources. Optional, defaults to ['photo', 'attach']
 278          * @param int              $limit       Limit of the process batch size, defaults to 5000
 279          *
 280          * @return int Number of moved resources
 281          * @throws Storage\StorageException
 282          * @throws Exception
 283          */
 284         public function move(Storage\IStorage $destination, array $tables = self::TABLES, int $limit = 5000)
 285         {
 286                 if (!$this->isValidBackend($destination, true)) {
 287                         throw new Storage\StorageException(sprintf("Can't move to storage backend '%s'", $destination::getName()));
 288                 }
 289
 290                 $moved = 0;
 291                 foreach ($tables as $table) {
 292                         // Get the rows where backend class is not the destination backend class
 293                         $resources = $this->dba->select(
 294                                 $table,
 295                                 ['id', 'data', 'backend-class', 'backend-ref'],
 296                                 ['`backend-class` IS NULL or `backend-class` != ?', $destination::getName()],
 297                                 ['limit' => $limit]
 298                         );
 299
 300                         while ($resource = $this->dba->fetch($resources)) {
 301                                 $id        = $resource['id'];
 302                                 $data      = $resource['data'];
 303                                 $source    = $this->getByName($resource['backend-class']);
 304                                 $sourceRef = $resource['backend-ref'];
 305
 306                                 if (!empty($source)) {
 307                                         $this->logger->info('Get data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 308                                         $data = $source->get($sourceRef);
 309                                 }
 310
 311                                 $this->logger->info('Save data to new backend.', ['newBackend' => $destination::getName()]);
 312                                 $destinationRef = $destination->put($data);
 313                                 $this->logger->info('Saved data.', ['newReference' => $destinationRef]);
 314
 315                                 if ($destinationRef !== '') {
 316                                         $this->logger->info('update row');
 317                                         if ($this->dba->update($table, ['backend-class' => $destination::getName(), 'backend-ref' => $destinationRef, 'data' => ''], ['id' => $id])) {
 318                                                 if (!empty($source)) {
 319                                                         $this->logger->info('Delete data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 320                                                         $source->delete($sourceRef);
 321                                                 }
 322                                                 $moved++;
 323                                         }
 324                                 }
 325                         }
 326
 327                         $this->dba->close($resources);
 328                 }
 329
 330                 return $moved;
 331         }
 332 }