Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\migrate;
Chris@0: 
Chris@0: use Drupal\Component\Utility\Bytes;
Chris@0: use Drupal\Core\Utility\Error;
Chris@0: use Drupal\Core\StringTranslation\StringTranslationTrait;
Chris@0: use Drupal\migrate\Event\MigrateEvents;
Chris@0: use Drupal\migrate\Event\MigrateImportEvent;
Chris@0: use Drupal\migrate\Event\MigratePostRowSaveEvent;
Chris@0: use Drupal\migrate\Event\MigratePreRowSaveEvent;
Chris@0: use Drupal\migrate\Event\MigrateRollbackEvent;
Chris@0: use Drupal\migrate\Event\MigrateRowDeleteEvent;
Chris@0: use Drupal\migrate\Exception\RequirementsException;
Chris@0: use Drupal\migrate\Plugin\MigrateIdMapInterface;
Chris@0: use Drupal\migrate\Plugin\MigrationInterface;
Chris@0: use Symfony\Component\EventDispatcher\EventDispatcherInterface;
Chris@0: 
Chris@0: /**
Chris@0:  * Defines a migrate executable class.
Chris@0:  */
Chris@0: class MigrateExecutable implements MigrateExecutableInterface {
Chris@0:   use StringTranslationTrait;
Chris@0: 
Chris@0:   /**
Chris@0:    * The configuration of the migration to do.
Chris@0:    *
Chris@0:    * @var \Drupal\migrate\Plugin\MigrationInterface
Chris@0:    */
Chris@0:   protected $migration;
Chris@0: 
Chris@0:   /**
Chris@0:    * Status of one row.
Chris@0:    *
Chris@0:    * The value is a MigrateIdMapInterface::STATUS_* constant, for example:
Chris@0:    * STATUS_IMPORTED.
Chris@0:    *
Chris@0:    * @var int
Chris@0:    */
Chris@0:   protected $sourceRowStatus;
Chris@0: 
Chris@0:   /**
Chris@0:    * The ratio of the memory limit at which an operation will be interrupted.
Chris@0:    *
Chris@0:    * @var float
Chris@0:    */
Chris@0:   protected $memoryThreshold = 0.85;
Chris@0: 
Chris@0:   /**
Chris@0:    * The PHP memory_limit expressed in bytes.
Chris@0:    *
Chris@0:    * @var int
Chris@0:    */
Chris@0:   protected $memoryLimit;
Chris@0: 
Chris@0:   /**
Chris@0:    * The configuration values of the source.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $sourceIdValues;
Chris@0: 
Chris@0:   /**
Chris@0:    * An array of counts. Initially used for cache hit/miss tracking.
Chris@0:    *
Chris@0:    * @var array
Chris@0:    */
Chris@0:   protected $counts = [];
Chris@0: 
Chris@0:   /**
Chris@0:    * The source.
Chris@0:    *
Chris@0:    * @var \Drupal\migrate\Plugin\MigrateSourceInterface
Chris@0:    */
Chris@0:   protected $source;
Chris@0: 
Chris@0:   /**
Chris@0:    * The event dispatcher.
Chris@0:    *
Chris@0:    * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
Chris@0:    */
Chris@0:   protected $eventDispatcher;
Chris@0: 
Chris@0:   /**
Chris@0:    * Migration message service.
Chris@0:    *
Chris@0:    * @todo https://www.drupal.org/node/2822663 Make this protected.
Chris@0:    *
Chris@0:    * @var \Drupal\migrate\MigrateMessageInterface
Chris@0:    */
Chris@0:   public $message;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs a MigrateExecutable and verifies and sets the memory limit.
Chris@0:    *
Chris@0:    * @param \Drupal\migrate\Plugin\MigrationInterface $migration
Chris@0:    *   The migration to run.
Chris@0:    * @param \Drupal\migrate\MigrateMessageInterface $message
Chris@14:    *   (optional) The migrate message service.
Chris@0:    * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
Chris@14:    *   (optional) The event dispatcher.
Chris@0:    *
Chris@0:    * @throws \Drupal\migrate\MigrateException
Chris@0:    */
Chris@14:   public function __construct(MigrationInterface $migration, MigrateMessageInterface $message = NULL, EventDispatcherInterface $event_dispatcher = NULL) {
Chris@0:     $this->migration = $migration;
Chris@14:     $this->message = $message ?: new MigrateMessage();
Chris@18:     $this->getIdMap()->setMessage($this->message);
Chris@0:     $this->eventDispatcher = $event_dispatcher;
Chris@0:     // Record the memory limit in bytes
Chris@0:     $limit = trim(ini_get('memory_limit'));
Chris@0:     if ($limit == '-1') {
Chris@0:       $this->memoryLimit = PHP_INT_MAX;
Chris@0:     }
Chris@0:     else {
Chris@0:       $this->memoryLimit = Bytes::toInt($limit);
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Returns the source.
Chris@0:    *
Chris@0:    * Makes sure source is initialized based on migration settings.
Chris@0:    *
Chris@0:    * @return \Drupal\migrate\Plugin\MigrateSourceInterface
Chris@0:    *   The source.
Chris@0:    */
Chris@0:   protected function getSource() {
Chris@0:     if (!isset($this->source)) {
Chris@0:       $this->source = $this->migration->getSourcePlugin();
Chris@0:     }
Chris@0:     return $this->source;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Gets the event dispatcher.
Chris@0:    *
Chris@0:    * @return \Symfony\Component\EventDispatcher\EventDispatcherInterface
Chris@0:    */
Chris@0:   protected function getEventDispatcher() {
Chris@0:     if (!$this->eventDispatcher) {
Chris@0:       $this->eventDispatcher = \Drupal::service('event_dispatcher');
Chris@0:     }
Chris@0:     return $this->eventDispatcher;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function import() {
Chris@0:     // Only begin the import operation if the migration is currently idle.
Chris@0:     if ($this->migration->getStatus() !== MigrationInterface::STATUS_IDLE) {
Chris@0:       $this->message->display($this->t('Migration @id is busy with another operation: @status',
Chris@0:         [
Chris@0:           '@id' => $this->migration->id(),
Chris@0:           '@status' => $this->t($this->migration->getStatusLabel()),
Chris@0:         ]), 'error');
Chris@0:       return MigrationInterface::RESULT_FAILED;
Chris@0:     }
Chris@0:     $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_IMPORT, new MigrateImportEvent($this->migration, $this->message));
Chris@0: 
Chris@0:     // Knock off migration if the requirements haven't been met.
Chris@0:     try {
Chris@0:       $this->migration->checkRequirements();
Chris@0:     }
Chris@0:     catch (RequirementsException $e) {
Chris@0:       $this->message->display(
Chris@0:         $this->t(
Chris@0:           'Migration @id did not meet the requirements. @message @requirements',
Chris@0:           [
Chris@0:             '@id' => $this->migration->id(),
Chris@0:             '@message' => $e->getMessage(),
Chris@0:             '@requirements' => $e->getRequirementsString(),
Chris@0:           ]
Chris@0:         ),
Chris@0:         'error'
Chris@0:       );
Chris@0: 
Chris@0:       return MigrationInterface::RESULT_FAILED;
Chris@0:     }
Chris@0: 
Chris@0:     $this->migration->setStatus(MigrationInterface::STATUS_IMPORTING);
Chris@0:     $return = MigrationInterface::RESULT_COMPLETED;
Chris@0:     $source = $this->getSource();
Chris@18:     $id_map = $this->getIdMap();
Chris@0: 
Chris@0:     try {
Chris@0:       $source->rewind();
Chris@0:     }
Chris@0:     catch (\Exception $e) {
Chris@0:       $this->message->display(
Chris@0:         $this->t('Migration failed with source plugin exception: @e', ['@e' => $e->getMessage()]), 'error');
Chris@0:       $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
Chris@0:       return MigrationInterface::RESULT_FAILED;
Chris@0:     }
Chris@0: 
Chris@0:     $destination = $this->migration->getDestinationPlugin();
Chris@0:     while ($source->valid()) {
Chris@0:       $row = $source->current();
Chris@0:       $this->sourceIdValues = $row->getSourceIdValues();
Chris@0: 
Chris@0:       try {
Chris@0:         $this->processRow($row);
Chris@0:         $save = TRUE;
Chris@0:       }
Chris@0:       catch (MigrateException $e) {
Chris@18:         $this->getIdMap()->saveIdMapping($row, [], $e->getStatus());
Chris@0:         $this->saveMessage($e->getMessage(), $e->getLevel());
Chris@0:         $save = FALSE;
Chris@0:       }
Chris@0:       catch (MigrateSkipRowException $e) {
Chris@0:         if ($e->getSaveToMap()) {
Chris@0:           $id_map->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_IGNORED);
Chris@0:         }
Chris@0:         if ($message = trim($e->getMessage())) {
Chris@0:           $this->saveMessage($message, MigrationInterface::MESSAGE_INFORMATIONAL);
Chris@0:         }
Chris@0:         $save = FALSE;
Chris@0:       }
Chris@0: 
Chris@0:       if ($save) {
Chris@0:         try {
Chris@0:           $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_ROW_SAVE, new MigratePreRowSaveEvent($this->migration, $this->message, $row));
Chris@17:           $destination_ids = $id_map->lookupDestinationIds($this->sourceIdValues);
Chris@17:           $destination_id_values = $destination_ids ? reset($destination_ids) : [];
Chris@17:           $destination_id_values = $destination->import($row, $destination_id_values);
Chris@0:           $this->getEventDispatcher()->dispatch(MigrateEvents::POST_ROW_SAVE, new MigratePostRowSaveEvent($this->migration, $this->message, $row, $destination_id_values));
Chris@0:           if ($destination_id_values) {
Chris@0:             // We do not save an idMap entry for config.
Chris@0:             if ($destination_id_values !== TRUE) {
Chris@0:               $id_map->saveIdMapping($row, $destination_id_values, $this->sourceRowStatus, $destination->rollbackAction());
Chris@0:             }
Chris@0:           }
Chris@0:           else {
Chris@0:             $id_map->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_FAILED);
Chris@0:             if (!$id_map->messageCount()) {
Chris@0:               $message = $this->t('New object was not saved, no error provided');
Chris@0:               $this->saveMessage($message);
Chris@0:               $this->message->display($message);
Chris@0:             }
Chris@0:           }
Chris@0:         }
Chris@0:         catch (MigrateException $e) {
Chris@18:           $this->getIdMap()->saveIdMapping($row, [], $e->getStatus());
Chris@0:           $this->saveMessage($e->getMessage(), $e->getLevel());
Chris@0:         }
Chris@0:         catch (\Exception $e) {
Chris@18:           $this->getIdMap()->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_FAILED);
Chris@0:           $this->handleException($e);
Chris@0:         }
Chris@0:       }
Chris@0: 
Chris@0:       $this->sourceRowStatus = MigrateIdMapInterface::STATUS_IMPORTED;
Chris@0: 
Chris@0:       // Check for memory exhaustion.
Chris@0:       if (($return = $this->checkStatus()) != MigrationInterface::RESULT_COMPLETED) {
Chris@0:         break;
Chris@0:       }
Chris@0: 
Chris@0:       // If anyone has requested we stop, return the requested result.
Chris@0:       if ($this->migration->getStatus() == MigrationInterface::STATUS_STOPPING) {
Chris@0:         $return = $this->migration->getInterruptionResult();
Chris@0:         $this->migration->clearInterruptionResult();
Chris@0:         break;
Chris@0:       }
Chris@0: 
Chris@0:       try {
Chris@0:         $source->next();
Chris@0:       }
Chris@0:       catch (\Exception $e) {
Chris@0:         $this->message->display(
Chris@0:           $this->t('Migration failed with source plugin exception: @e',
Chris@0:             ['@e' => $e->getMessage()]), 'error');
Chris@0:         $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
Chris@0:         return MigrationInterface::RESULT_FAILED;
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     $this->getEventDispatcher()->dispatch(MigrateEvents::POST_IMPORT, new MigrateImportEvent($this->migration, $this->message));
Chris@0:     $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
Chris@0:     return $return;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function rollback() {
Chris@0:     // Only begin the rollback operation if the migration is currently idle.
Chris@0:     if ($this->migration->getStatus() !== MigrationInterface::STATUS_IDLE) {
Chris@0:       $this->message->display($this->t('Migration @id is busy with another operation: @status', ['@id' => $this->migration->id(), '@status' => $this->t($this->migration->getStatusLabel())]), 'error');
Chris@0:       return MigrationInterface::RESULT_FAILED;
Chris@0:     }
Chris@0: 
Chris@0:     // Announce that rollback is about to happen.
Chris@0:     $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_ROLLBACK, new MigrateRollbackEvent($this->migration));
Chris@0: 
Chris@0:     // Optimistically assume things are going to work out; if not, $return will be
Chris@0:     // updated to some other status.
Chris@0:     $return = MigrationInterface::RESULT_COMPLETED;
Chris@0: 
Chris@0:     $this->migration->setStatus(MigrationInterface::STATUS_ROLLING_BACK);
Chris@18:     $id_map = $this->getIdMap();
Chris@0:     $destination = $this->migration->getDestinationPlugin();
Chris@0: 
Chris@0:     // Loop through each row in the map, and try to roll it back.
Chris@18:     $id_map->rewind();
Chris@18:     while ($id_map->valid()) {
Chris@0:       $destination_key = $id_map->currentDestination();
Chris@0:       if ($destination_key) {
Chris@0:         $map_row = $id_map->getRowByDestination($destination_key);
Chris@0:         if ($map_row['rollback_action'] == MigrateIdMapInterface::ROLLBACK_DELETE) {
Chris@0:           $this->getEventDispatcher()
Chris@0:             ->dispatch(MigrateEvents::PRE_ROW_DELETE, new MigrateRowDeleteEvent($this->migration, $destination_key));
Chris@0:           $destination->rollback($destination_key);
Chris@0:           $this->getEventDispatcher()
Chris@0:             ->dispatch(MigrateEvents::POST_ROW_DELETE, new MigrateRowDeleteEvent($this->migration, $destination_key));
Chris@0:         }
Chris@0:         // We're now done with this row, so remove it from the map.
Chris@0:         $id_map->deleteDestination($destination_key);
Chris@0:       }
Chris@0:       else {
Chris@0:         // If there is no destination key the import probably failed and we can
Chris@0:         // remove the row without further action.
Chris@0:         $source_key = $id_map->currentSource();
Chris@0:         $id_map->delete($source_key);
Chris@0:       }
Chris@18:       $id_map->next();
Chris@0: 
Chris@0:       // Check for memory exhaustion.
Chris@0:       if (($return = $this->checkStatus()) != MigrationInterface::RESULT_COMPLETED) {
Chris@0:         break;
Chris@0:       }
Chris@0: 
Chris@0:       // If anyone has requested we stop, return the requested result.
Chris@0:       if ($this->migration->getStatus() == MigrationInterface::STATUS_STOPPING) {
Chris@0:         $return = $this->migration->getInterruptionResult();
Chris@0:         $this->migration->clearInterruptionResult();
Chris@0:         break;
Chris@0:       }
Chris@0:     }
Chris@0: 
Chris@0:     // Notify modules that rollback attempt was complete.
Chris@0:     $this->getEventDispatcher()->dispatch(MigrateEvents::POST_ROLLBACK, new MigrateRollbackEvent($this->migration));
Chris@0:     $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
Chris@0: 
Chris@0:     return $return;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@18:    * Get the ID map from the current migration.
Chris@18:    *
Chris@18:    * @return \Drupal\migrate\Plugin\MigrateIdMapInterface
Chris@18:    *   The ID map.
Chris@18:    */
Chris@18:   protected function getIdMap() {
Chris@18:     return $this->migration->getIdMap();
Chris@18:   }
Chris@18: 
Chris@18:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function processRow(Row $row, array $process = NULL, $value = NULL) {
Chris@0:     foreach ($this->migration->getProcessPlugins($process) as $destination => $plugins) {
Chris@0:       $multiple = FALSE;
Chris@0:       /** @var $plugin \Drupal\migrate\Plugin\MigrateProcessInterface */
Chris@0:       foreach ($plugins as $plugin) {
Chris@0:         $definition = $plugin->getPluginDefinition();
Chris@0:         // Many plugins expect a scalar value but the current value of the
Chris@0:         // pipeline might be multiple scalars (this is set by the previous
Chris@0:         // plugin) and in this case the current value needs to be iterated
Chris@0:         // and each scalar separately transformed.
Chris@0:         if ($multiple && !$definition['handle_multiples']) {
Chris@0:           $new_value = [];
Chris@0:           if (!is_array($value)) {
Chris@0:             throw new MigrateException(sprintf('Pipeline failed at %s plugin for destination %s: %s received instead of an array,', $plugin->getPluginId(), $destination, $value));
Chris@0:           }
Chris@0:           $break = FALSE;
Chris@0:           foreach ($value as $scalar_value) {
Chris@0:             try {
Chris@0:               $new_value[] = $plugin->transform($scalar_value, $this, $row, $destination);
Chris@0:             }
Chris@0:             catch (MigrateSkipProcessException $e) {
Chris@0:               $new_value[] = NULL;
Chris@0:               $break = TRUE;
Chris@0:             }
Chris@0:           }
Chris@0:           $value = $new_value;
Chris@0:           if ($break) {
Chris@0:             break;
Chris@0:           }
Chris@0:         }
Chris@0:         else {
Chris@0:           try {
Chris@0:             $value = $plugin->transform($value, $this, $row, $destination);
Chris@0:           }
Chris@0:           catch (MigrateSkipProcessException $e) {
Chris@0:             $value = NULL;
Chris@0:             break;
Chris@0:           }
Chris@0:           $multiple = $plugin->multiple();
Chris@0:         }
Chris@0:       }
Chris@0:       // Ensure all values, including nulls, are migrated.
Chris@0:       if ($plugins) {
Chris@0:         if (isset($value)) {
Chris@0:           $row->setDestinationProperty($destination, $value);
Chris@0:         }
Chris@0:         else {
Chris@0:           $row->setEmptyDestinationProperty($destination);
Chris@0:         }
Chris@0:       }
Chris@0:       // Reset the value.
Chris@0:       $value = NULL;
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Fetches the key array for the current source record.
Chris@0:    *
Chris@0:    * @return array
Chris@0:    *   The current source IDs.
Chris@0:    */
Chris@0:   protected function currentSourceIds() {
Chris@0:     return $this->getSource()->getCurrentIds();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function saveMessage($message, $level = MigrationInterface::MESSAGE_ERROR) {
Chris@18:     $this->getIdMap()->saveMessage($this->sourceIdValues, $message, $level);
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Takes an Exception object and both saves and displays it.
Chris@0:    *
Chris@0:    * Pulls in additional information on the location triggering the exception.
Chris@0:    *
Chris@0:    * @param \Exception $exception
Chris@0:    *   Object representing the exception.
Chris@0:    * @param bool $save
Chris@0:    *   (optional) Whether to save the message in the migration's mapping table.
Chris@0:    *   Set to FALSE in contexts where this doesn't make sense.
Chris@0:    */
Chris@0:   protected function handleException(\Exception $exception, $save = TRUE) {
Chris@0:     $result = Error::decodeException($exception);
Chris@0:     $message = $result['@message'] . ' (' . $result['%file'] . ':' . $result['%line'] . ')';
Chris@0:     if ($save) {
Chris@0:       $this->saveMessage($message);
Chris@0:     }
Chris@0:     $this->message->display($message, 'error');
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Checks for exceptional conditions, and display feedback.
Chris@0:    */
Chris@0:   protected function checkStatus() {
Chris@0:     if ($this->memoryExceeded()) {
Chris@0:       return MigrationInterface::RESULT_INCOMPLETE;
Chris@0:     }
Chris@0:     return MigrationInterface::RESULT_COMPLETED;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Tests whether we've exceeded the desired memory threshold.
Chris@0:    *
Chris@0:    * If so, output a message.
Chris@0:    *
Chris@0:    * @return bool
Chris@0:    *   TRUE if the threshold is exceeded, otherwise FALSE.
Chris@0:    */
Chris@0:   protected function memoryExceeded() {
Chris@0:     $usage = $this->getMemoryUsage();
Chris@0:     $pct_memory = $usage / $this->memoryLimit;
Chris@0:     if (!$threshold = $this->memoryThreshold) {
Chris@0:       return FALSE;
Chris@0:     }
Chris@0:     if ($pct_memory > $threshold) {
Chris@0:       $this->message->display(
Chris@0:         $this->t(
Chris@0:           'Memory usage is @usage (@pct% of limit @limit), reclaiming memory.',
Chris@0:           [
Chris@0:             '@pct' => round($pct_memory * 100),
Chris@0:             '@usage' => $this->formatSize($usage),
Chris@0:             '@limit' => $this->formatSize($this->memoryLimit),
Chris@0:           ]
Chris@0:         ),
Chris@0:         'warning'
Chris@0:       );
Chris@0:       $usage = $this->attemptMemoryReclaim();
Chris@0:       $pct_memory = $usage / $this->memoryLimit;
Chris@0:       // Use a lower threshold - we don't want to be in a situation where we keep
Chris@0:       // coming back here and trimming a tiny amount
Chris@0:       if ($pct_memory > (0.90 * $threshold)) {
Chris@0:         $this->message->display(
Chris@0:           $this->t(
Chris@0:             'Memory usage is now @usage (@pct% of limit @limit), not enough reclaimed, starting new batch',
Chris@0:             [
Chris@0:               '@pct' => round($pct_memory * 100),
Chris@0:               '@usage' => $this->formatSize($usage),
Chris@0:               '@limit' => $this->formatSize($this->memoryLimit),
Chris@0:             ]
Chris@0:           ),
Chris@0:           'warning'
Chris@0:         );
Chris@0:         return TRUE;
Chris@0:       }
Chris@0:       else {
Chris@0:         $this->message->display(
Chris@0:           $this->t(
Chris@0:             'Memory usage is now @usage (@pct% of limit @limit), reclaimed enough, continuing',
Chris@0:             [
Chris@0:               '@pct' => round($pct_memory * 100),
Chris@0:               '@usage' => $this->formatSize($usage),
Chris@0:               '@limit' => $this->formatSize($this->memoryLimit),
Chris@0:             ]
Chris@0:           ),
Chris@0:           'warning');
Chris@0:         return FALSE;
Chris@0:       }
Chris@0:     }
Chris@0:     else {
Chris@0:       return FALSE;
Chris@0:     }
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Returns the memory usage so far.
Chris@0:    *
Chris@0:    * @return int
Chris@0:    *   The memory usage.
Chris@0:    */
Chris@0:   protected function getMemoryUsage() {
Chris@0:     return memory_get_usage();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Tries to reclaim memory.
Chris@0:    *
Chris@0:    * @return int
Chris@0:    *   The memory usage after reclaim.
Chris@0:    */
Chris@0:   protected function attemptMemoryReclaim() {
Chris@0:     // First, try resetting Drupal's static storage - this frequently releases
Chris@0:     // plenty of memory to continue.
Chris@0:     drupal_static_reset();
Chris@0: 
Chris@0:     // Entity storage can blow up with caches so clear them out.
Chris@0:     $manager = \Drupal::entityManager();
Chris@0:     foreach ($manager->getDefinitions() as $id => $definition) {
Chris@0:       $manager->getStorage($id)->resetCache();
Chris@0:     }
Chris@0: 
Chris@0:     // @TODO: explore resetting the container.
Chris@0: 
Chris@0:     // Run garbage collector to further reduce memory.
Chris@0:     gc_collect_cycles();
Chris@0: 
Chris@0:     return memory_get_usage();
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Generates a string representation for the given byte count.
Chris@0:    *
Chris@0:    * @param int $size
Chris@0:    *   A size in bytes.
Chris@0:    *
Chris@0:    * @return string
Chris@0:    *   A translated string representation of the size.
Chris@0:    */
Chris@0:   protected function formatSize($size) {
Chris@0:     return format_size($size);
Chris@0:   }
Chris@0: 
Chris@0: }