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 Friendica\Network\HTTPException\InternalServerErrorException;
  29 use Psr\Log\LoggerInterface;
  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\IWritableStorage */
  65         private $currentBackend;
  66
  67         /**
  68          * @param Database        $dba
  69          * @param IConfig         $config
  70          * @param LoggerInterface $logger
  71          * @param L10n            $l10n
  72          *
  73          * @throws Storage\InvalidClassStorageException in case the active backend class is invalid
  74          * @throws Storage\StorageException in case of unexpected errors during the active backend class loading
  75          */
  76         public function __construct(Database $dba, IConfig $config, LoggerInterface $logger, L10n $l10n)
  77         {
  78                 $this->dba      = $dba;
  79                 $this->config   = $config;
  80                 $this->logger   = $logger;
  81                 $this->l10n     = $l10n;
  82                 $this->backends = $config->get('storage', 'backends', self::DEFAULT_BACKENDS);
  83
  84                 $currentName = $this->config->get('storage', 'name');
  85
  86                 // you can only use user backends as a "default" backend, so the second parameter is true
  87                 $this->currentBackend = $this->getWritableStorageByName($currentName);
  88         }
  89
  90         /**
  91          * Return current storage backend class
  92          *
  93          * @return Storage\IWritableStorage
  94          */
  95         public function getBackend()
  96         {
  97                 return $this->currentBackend;
  98         }
  99
 100         /**
 101          * Returns a writable storage backend class by registered name
 102          *
 103          * @param string $name Backend name
 104          *
 105          * @return Storage\IWritableStorage
 106          *
 107          * @throws Storage\InvalidClassStorageException in case there's no backend class for the name
 108          * @throws Storage\StorageException in case of an unexpected failure during the hook call
 109          */
 110         public function getWritableStorageByName(string $name): Storage\IWritableStorage
 111         {
 112                 $storage = $this->getByName($name, $this->backends);
 113                 if ($storage instanceof Storage\IWritableStorage) {
 114                         return $storage;
 115                 } else {
 116                         throw new Storage\InvalidClassStorageException(sprintf('Backend %s is not writable', $name));
 117                 }
 118         }
 119
 120         /**
 121          * Return storage backend class by registered name
 122          *
 123          * @param string     $name Backend name
 124          * @param array|null $validBackends possible, manual override of the valid backends
 125          *
 126          * @return Storage\IStorage
 127          *
 128          * @throws Storage\InvalidClassStorageException in case there's no backend class for the name
 129          * @throws Storage\StorageException in case of an unexpected failure during the hook call
 130          */
 131         public function getByName(string $name, array $validBackends = null): Storage\IStorage
 132         {
 133                 // If there's no cached instance create a new instance
 134                 if (!isset($this->backendInstances[$name])) {
 135                         // If the current name isn't a valid backend (or the SystemResource instance) create it
 136                         if ($this->isValidBackend($name, $validBackends)) {
 137                                 switch ($name) {
 138                                         // Try the filesystem backend
 139                                         case Storage\Filesystem::getName():
 140                                                 $this->backendInstances[$name] = new Storage\Filesystem($this->config, $this->l10n);
 141                                                 break;
 142                                         // try the database backend
 143                                         case Storage\Database::getName():
 144                                                 $this->backendInstances[$name] = new Storage\Database($this->dba);
 145                                                 break;
 146                                         // at least, try if there's an addon for the backend
 147                                         case Storage\SystemResource::getName():
 148                                                 $this->backendInstances[$name] = new Storage\SystemResource();
 149                                                 break;
 150                                         case Storage\ExternalResource::getName():
 151                                                 $this->backendInstances[$name] = new Storage\ExternalResource();
 152                                                 break;
 153                                         default:
 154                                                 $data = [
 155                                                         'name'    => $name,
 156                                                         'storage' => null,
 157                                                 ];
 158                                                 try {
 159                                                         Hook::callAll('storage_instance', $data);
 160                                                         if (($data['storage'] ?? null) instanceof Storage\IStorage) {
 161                                                                 $this->backendInstances[$data['name'] ?? $name] = $data['storage'];
 162                                                         } else {
 163                                                                 throw new Storage\InvalidClassStorageException(sprintf('Backend %s was not found', $name));
 164                                                         }
 165                                                 } catch (InternalServerErrorException $exception) {
 166                                                         throw new Storage\StorageException(sprintf('Failed calling hook::storage_instance for backend %s', $name), $exception);
 167                                                 }
 168                                                 break;
 169                                 }
 170                         } else {
 171                                 throw new Storage\InvalidClassStorageException(sprintf('Backend %s is not valid', $name));
 172                         }
 173                 }
 174
 175                 return $this->backendInstances[$name];
 176         }
 177
 178         /**
 179          * Checks, if the storage is a valid backend
 180          *
 181          * @param string|null $name          The name or class of the backend
 182          * @param array|null  $validBackends Possible, valid backends to check
 183          *
 184          * @return boolean True, if the backend is a valid backend
 185          */
 186         public function isValidBackend(string $name = null, array $validBackends = null): bool
 187         {
 188                 $validBackends = $validBackends ?? array_merge($this->backends,
 189                                 [
 190                                         Storage\SystemResource::getName()   => '',
 191                                         Storage\ExternalResource::getName() => ''
 192                                 ]);
 193                 return array_key_exists($name, $validBackends);
 194         }
 195
 196         /**
 197          * Set current storage backend class
 198          *
 199          * @param Storage\IWritableStorage $storage The storage class
 200          *
 201          * @return boolean True, if the set was successful
 202          */
 203         public function setBackend(Storage\IWritableStorage $storage): bool
 204         {
 205                 if ($this->config->set('storage', 'name', $storage::getName())) {
 206                         $this->currentBackend = $storage;
 207                         return true;
 208                 } else {
 209                         return false;
 210                 }
 211         }
 212
 213         /**
 214          * Get registered backends
 215          *
 216          * @return array
 217          */
 218         public function listBackends(): array
 219         {
 220                 return $this->backends;
 221         }
 222
 223         /**
 224          * Register a storage backend class
 225          *
 226          * You have to register the hook "storage_instance" as well to make this class work!
 227          *
 228          * @param string $class Backend class name
 229          *
 230          * @return boolean True, if the registration was successful
 231          */
 232         public function register(string $class): bool
 233         {
 234                 if (is_subclass_of($class, Storage\IStorage::class)) {
 235                         /** @var Storage\IStorage $class */
 236
 237                         $backends                    = $this->backends;
 238                         $backends[$class::getName()] = $class;
 239
 240                         if ($this->config->set('storage', 'backends', $backends)) {
 241                                 $this->backends = $backends;
 242                                 return true;
 243                         } else {
 244                                 return false;
 245                         }
 246                 } else {
 247                         return false;
 248                 }
 249         }
 250
 251         /**
 252          * Unregister a storage backend class
 253          *
 254          * @param string $class Backend class name
 255          *
 256          * @return boolean True, if unregistering was successful
 257          */
 258         public function unregister(string $class): bool
 259         {
 260                 if (is_subclass_of($class, Storage\IStorage::class)) {
 261                         /** @var Storage\IStorage $class */
 262
 263                         unset($this->backends[$class::getName()]);
 264
 265                         if ($this->currentBackend instanceof $class) {
 266                                 $this->config->set('storage', 'name', null);
 267                                 $this->currentBackend = null;
 268                         }
 269
 270                         return $this->config->set('storage', 'backends', $this->backends);
 271                 } else {
 272                         return false;
 273                 }
 274         }
 275
 276         /**
 277          * Move up to 5000 resources to storage $dest
 278          *
 279          * Copy existing data to destination storage and delete from source.
 280          * This method cannot move to legacy in-table `data` field.
 281          *
 282          * @param Storage\IWritableStorage $destination Destination storage class name
 283          * @param array                    $tables      Tables to look in for resources. Optional, defaults to ['photo', 'attach']
 284          * @param int                      $limit       Limit of the process batch size, defaults to 5000
 285          *
 286          * @return int Number of moved resources
 287          * @throws Storage\StorageException
 288          * @throws Exception
 289          */
 290         public function move(Storage\IWritableStorage $destination, array $tables = self::TABLES, int $limit = 5000): int
 291         {
 292                 if (!$this->isValidBackend($destination, $this->backends)) {
 293                         throw new Storage\StorageException(sprintf("Can't move to storage backend '%s'", $destination::getName()));
 294                 }
 295
 296                 $moved = 0;
 297                 foreach ($tables as $table) {
 298                         // Get the rows where backend class is not the destination backend class
 299                         $resources = $this->dba->select(
 300                                 $table,
 301                                 ['id', 'data', 'backend-class', 'backend-ref'],
 302                                 ['`backend-class` IS NULL or `backend-class` != ?', $destination::getName()],
 303                                 ['limit' => $limit]
 304                         );
 305
 306                         while ($resource = $this->dba->fetch($resources)) {
 307                                 $id        = $resource['id'];
 308                                 $sourceRef = $resource['backend-ref'];
 309                                 $source    = null;
 310
 311                                 try {
 312                                         $source = $this->getWritableStorageByName($resource['backend-class'] ?? '');
 313                                         $this->logger->info('Get data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 314                                         $data = $source->get($sourceRef);
 315                                 } catch (Storage\InvalidClassStorageException $exception) {
 316                                         $this->logger->info('Get data from DB resource field.', ['oldReference' => $sourceRef]);
 317                                         $data = $resource['data'];
 318                                 } catch (Storage\ReferenceStorageException $exception) {
 319                                         $this->logger->info('Invalid source reference.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 320                                         continue;
 321                                 }
 322
 323                                 $this->logger->info('Save data to new backend.', ['newBackend' => $destination::getName()]);
 324                                 $destinationRef = $destination->put($data);
 325                                 $this->logger->info('Saved data.', ['newReference' => $destinationRef]);
 326
 327                                 if ($destinationRef !== '') {
 328                                         $this->logger->info('update row');
 329                                         if ($this->dba->update($table, ['backend-class' => $destination::getName(), 'backend-ref' => $destinationRef, 'data' => ''], ['id' => $id])) {
 330                                                 if (!empty($source)) {
 331                                                         $this->logger->info('Delete data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 332                                                         $source->delete($sourceRef);
 333                                                 }
 334                                                 $moved++;
 335                                         }
 336                                 }
 337                         }
 338
 339                         $this->dba->close($resources);
 340                 }
 341
 342                 return $moved;
 343         }
 344 }