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         /** @var string[]  */
  44         const DEFAULT_BACKENDS = [
  45                 Storage\Filesystem::NAME,
  46                 Storage\Database::NAME,
  47         ];
  48
  49         /** @var string[] List of valid backend classes */
  50         private $validBackends;
  51
  52         /**
  53          * @var Storage\IStorage[] A local cache for storage instances
  54          */
  55         private $backendInstances = [];
  56
  57         /** @var Database */
  58         private $dba;
  59         /** @var IConfig */
  60         private $config;
  61         /** @var LoggerInterface */
  62         private $logger;
  63         /** @var L10n */
  64         private $l10n;
  65
  66         /** @var Storage\IWritableStorage */
  67         private $currentBackend;
  68
  69         /**
  70          * @param Database        $dba
  71          * @param IConfig         $config
  72          * @param LoggerInterface $logger
  73          * @param L10n            $l10n
  74          *
  75          * @throws Storage\InvalidClassStorageException in case the active backend class is invalid
  76          * @throws Storage\StorageException in case of unexpected errors during the active backend class loading
  77          */
  78         public function __construct(Database $dba, IConfig $config, LoggerInterface $logger, L10n $l10n)
  79         {
  80                 $this->dba           = $dba;
  81                 $this->config        = $config;
  82                 $this->logger        = $logger;
  83                 $this->l10n          = $l10n;
  84                 $this->validBackends = $config->get('storage', 'backends', self::DEFAULT_BACKENDS);
  85
  86                 $currentName = $this->config->get('storage', 'name');
  87
  88                 // you can only use user backends as a "default" backend, so the second parameter is true
  89                 $this->currentBackend = $this->getWritableStorageByName($currentName);
  90         }
  91
  92         /**
  93          * Return current storage backend class
  94          *
  95          * @return Storage\IWritableStorage
  96          */
  97         public function getBackend()
  98         {
  99                 return $this->currentBackend;
 100         }
 101
 102         /**
 103          * Returns a writable storage backend class by registered name
 104          *
 105          * @param string $name Backend name
 106          *
 107          * @return Storage\IWritableStorage
 108          *
 109          * @throws Storage\InvalidClassStorageException in case there's no backend class for the name
 110          * @throws Storage\StorageException in case of an unexpected failure during the hook call
 111          */
 112         public function getWritableStorageByName(string $name): Storage\IWritableStorage
 113         {
 114                 $storage = $this->getByName($name, $this->validBackends);
 115                 if (!$storage instanceof Storage\IWritableStorage) {
 116                         throw new Storage\InvalidClassStorageException(sprintf('Backend %s is not writable', $name));
 117                 }
 118
 119                 return $storage;
 120         }
 121
 122         /**
 123          * Return storage backend class by registered name
 124          *
 125          * @param string     $name Backend name
 126          * @param string[]|null $validBackends possible, manual override of the valid backends
 127          *
 128          * @return Storage\IStorage
 129          *
 130          * @throws Storage\InvalidClassStorageException in case there's no backend class for the name
 131          * @throws Storage\StorageException in case of an unexpected failure during the hook call
 132          */
 133         public function getByName(string $name, array $validBackends = null): Storage\IStorage
 134         {
 135                 // If there's no cached instance create a new instance
 136                 if (!isset($this->backendInstances[$name])) {
 137                         // If the current name isn't a valid backend (or the SystemResource instance) create it
 138                         if (!$this->isValidBackend($name, $validBackends)) {
 139                                 throw new Storage\InvalidClassStorageException(sprintf('Backend %s is not valid', $name));
 140                         }
 141
 142                         switch ($name) {
 143                                 // Try the filesystem backend
 144                                 case Storage\Filesystem::getName():
 145                                         $this->backendInstances[$name] = new Storage\Filesystem($this->config, $this->l10n);
 146                                         break;
 147                                 // try the database backend
 148                                 case Storage\Database::getName():
 149                                         $this->backendInstances[$name] = new Storage\Database($this->dba);
 150                                         break;
 151                                 // at least, try if there's an addon for the backend
 152                                 case Storage\SystemResource::getName():
 153                                         $this->backendInstances[$name] = new Storage\SystemResource();
 154                                         break;
 155                                 case Storage\ExternalResource::getName():
 156                                         $this->backendInstances[$name] = new Storage\ExternalResource();
 157                                         break;
 158                                 default:
 159                                         $data = [
 160                                                 'name'    => $name,
 161                                                 'storage' => null,
 162                                         ];
 163                                         try {
 164                                                 Hook::callAll('storage_instance', $data);
 165                                                 if (!($data['storage'] ?? null) instanceof Storage\IStorage) {
 166                                                         throw new Storage\InvalidClassStorageException(sprintf('Backend %s was not found', $name));
 167                                                 }
 168
 169                                                 $this->backendInstances[$data['name'] ?? $name] = $data['storage'];
 170                                         } catch (InternalServerErrorException $exception) {
 171                                                 throw new Storage\StorageException(sprintf('Failed calling hook::storage_instance for backend %s', $name), $exception);
 172                                         }
 173                                         break;
 174                         }
 175                 }
 176
 177                 return $this->backendInstances[$name];
 178         }
 179
 180         /**
 181          * Checks, if the storage is a valid backend
 182          *
 183          * @param string|null   $name          The name or class of the backend
 184          * @param string[]|null $validBackends Possible, valid backends to check
 185          *
 186          * @return boolean True, if the backend is a valid backend
 187          */
 188         public function isValidBackend(string $name = null, array $validBackends = null): bool
 189         {
 190                 $validBackends = $validBackends ?? array_merge($this->validBackends,
 191                                 [
 192                                         Storage\SystemResource::getName(),
 193                                         Storage\ExternalResource::getName(),
 194                                 ]);
 195                 return in_array($name, $validBackends);
 196         }
 197
 198         /**
 199          * Set current storage backend class
 200          *
 201          * @param Storage\IWritableStorage $storage The storage class
 202          *
 203          * @return boolean True, if the set was successful
 204          */
 205         public function setBackend(Storage\IWritableStorage $storage): bool
 206         {
 207                 if ($this->config->set('storage', 'name', $storage::getName())) {
 208                         $this->currentBackend = $storage;
 209                         return true;
 210                 } else {
 211                         return false;
 212                 }
 213         }
 214
 215         /**
 216          * Get registered backends
 217          *
 218          * @return string[]
 219          */
 220         public function listBackends(): array
 221         {
 222                 return $this->validBackends;
 223         }
 224
 225         /**
 226          * Register a storage backend class
 227          *
 228          * You have to register the hook "storage_instance" as well to make this class work!
 229          *
 230          * @param string $class Backend class name
 231          *
 232          * @return boolean True, if the registration was successful
 233          */
 234         public function register(string $class): bool
 235         {
 236                 if (is_subclass_of($class, Storage\IStorage::class)) {
 237                         /** @var Storage\IStorage $class */
 238
 239                         if ($this->isValidBackend($class::getName(), $this->validBackends)) {
 240                                 return true;
 241                         }
 242
 243                         $backends   = $this->validBackends;
 244                         $backends[] = $class::getName();
 245
 246                         if ($this->config->set('storage', 'backends', $backends)) {
 247                                 $this->validBackends = $backends;
 248                                 return true;
 249                         } else {
 250                                 return false;
 251                         }
 252                 } else {
 253                         return false;
 254                 }
 255         }
 256
 257         /**
 258          * Unregister a storage backend class
 259          *
 260          * @param string $class Backend class name
 261          *
 262          * @return boolean True, if unregistering was successful
 263          *
 264          * @throws Storage\StorageException
 265          */
 266         public function unregister(string $class): bool
 267         {
 268                 if (is_subclass_of($class, Storage\IStorage::class)) {
 269                         /** @var Storage\IStorage $class */
 270
 271                         if ($this->currentBackend::getName() == $class::getName()) {
 272                                 throw new Storage\StorageException(sprintf('Cannot unregister %s, because it\'s currently active.', $class::getName()));
 273                         }
 274
 275                         $key = array_search($class::getName(), $this->validBackends);
 276
 277                         if ($key !== false) {
 278                                 $backends = $this->validBackends;
 279                                 unset($backends[$key]);
 280                                 $backends = array_values($backends);
 281                                 if ($this->config->set('storage', 'backends', $backends)) {
 282                                         $this->validBackends = $backends;
 283                                         return true;
 284                                 } else {
 285                                         return false;
 286                                 }
 287                         } else {
 288                                 return true;
 289                         }
 290                 } else {
 291                         return false;
 292                 }
 293         }
 294
 295         /**
 296          * Move up to 5000 resources to storage $dest
 297          *
 298          * Copy existing data to destination storage and delete from source.
 299          * This method cannot move to legacy in-table `data` field.
 300          *
 301          * @param Storage\IWritableStorage $destination Destination storage class name
 302          * @param array                    $tables      Tables to look in for resources. Optional, defaults to ['photo', 'attach']
 303          * @param int                      $limit       Limit of the process batch size, defaults to 5000
 304          *
 305          * @return int Number of moved resources
 306          * @throws Storage\StorageException
 307          * @throws Exception
 308          */
 309         public function move(Storage\IWritableStorage $destination, array $tables = self::TABLES, int $limit = 5000): int
 310         {
 311                 if (!$this->isValidBackend($destination, $this->validBackends)) {
 312                         throw new Storage\StorageException(sprintf("Can't move to storage backend '%s'", $destination::getName()));
 313                 }
 314
 315                 $moved = 0;
 316                 foreach ($tables as $table) {
 317                         // Get the rows where backend class is not the destination backend class
 318                         $resources = $this->dba->select(
 319                                 $table,
 320                                 ['id', 'data', 'backend-class', 'backend-ref'],
 321                                 ['`backend-class` IS NULL or `backend-class` != ?', $destination::getName()],
 322                                 ['limit' => $limit]
 323                         );
 324
 325                         while ($resource = $this->dba->fetch($resources)) {
 326                                 $id        = $resource['id'];
 327                                 $sourceRef = $resource['backend-ref'];
 328                                 $source    = null;
 329
 330                                 try {
 331                                         $source = $this->getWritableStorageByName($resource['backend-class'] ?? '');
 332                                         $this->logger->info('Get data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 333                                         $data = $source->get($sourceRef);
 334                                 } catch (Storage\InvalidClassStorageException $exception) {
 335                                         $this->logger->info('Get data from DB resource field.', ['oldReference' => $sourceRef]);
 336                                         $data = $resource['data'];
 337                                 } catch (Storage\ReferenceStorageException $exception) {
 338                                         $this->logger->info('Invalid source reference.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 339                                         continue;
 340                                 }
 341
 342                                 $this->logger->info('Save data to new backend.', ['newBackend' => $destination::getName()]);
 343                                 $destinationRef = $destination->put($data);
 344                                 $this->logger->info('Saved data.', ['newReference' => $destinationRef]);
 345
 346                                 if ($destinationRef !== '') {
 347                                         $this->logger->info('update row');
 348                                         if ($this->dba->update($table, ['backend-class' => $destination::getName(), 'backend-ref' => $destinationRef, 'data' => ''], ['id' => $id])) {
 349                                                 if (!empty($source)) {
 350                                                         $this->logger->info('Delete data from old backend.', ['oldBackend' => $source, 'oldReference' => $sourceRef]);
 351                                                         $source->delete($sourceRef);
 352                                                 }
 353                                                 $moved++;
 354                                         }
 355                                 }
 356                         }
 357
 358                         $this->dba->close($resources);
 359                 }
 360
 361                 return $moved;
 362         }
 363 }