diff core/modules/migrate/src/MigrateExecutable.php @ 0:c75dbcec494b

Initial commit from drush-created site

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/modules/migrate/src/MigrateExecutable.php	Thu Jul 05 14:24:15 2018 +0000
@@ -0,0 +1,561 @@
+<?php
+
+namespace Drupal\migrate;
+
+use Drupal\Component\Utility\Bytes;
+use Drupal\Core\Utility\Error;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Drupal\migrate\Event\MigrateEvents;
+use Drupal\migrate\Event\MigrateImportEvent;
+use Drupal\migrate\Event\MigratePostRowSaveEvent;
+use Drupal\migrate\Event\MigratePreRowSaveEvent;
+use Drupal\migrate\Event\MigrateRollbackEvent;
+use Drupal\migrate\Event\MigrateRowDeleteEvent;
+use Drupal\migrate\Exception\RequirementsException;
+use Drupal\migrate\Plugin\MigrateIdMapInterface;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+
+/**
+ * Defines a migrate executable class.
+ */
+class MigrateExecutable implements MigrateExecutableInterface {
+  use StringTranslationTrait;
+
+  /**
+   * The configuration of the migration to do.
+   *
+   * @var \Drupal\migrate\Plugin\MigrationInterface
+   */
+  protected $migration;
+
+  /**
+   * Status of one row.
+   *
+   * The value is a MigrateIdMapInterface::STATUS_* constant, for example:
+   * STATUS_IMPORTED.
+   *
+   * @var int
+   */
+  protected $sourceRowStatus;
+
+  /**
+   * The ratio of the memory limit at which an operation will be interrupted.
+   *
+   * @var float
+   */
+  protected $memoryThreshold = 0.85;
+
+  /**
+   * The PHP memory_limit expressed in bytes.
+   *
+   * @var int
+   */
+  protected $memoryLimit;
+
+  /**
+   * The configuration values of the source.
+   *
+   * @var array
+   */
+  protected $sourceIdValues;
+
+  /**
+   * An array of counts. Initially used for cache hit/miss tracking.
+   *
+   * @var array
+   */
+  protected $counts = [];
+
+  /**
+   * The source.
+   *
+   * @var \Drupal\migrate\Plugin\MigrateSourceInterface
+   */
+  protected $source;
+
+  /**
+   * The event dispatcher.
+   *
+   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   */
+  protected $eventDispatcher;
+
+  /**
+   * Migration message service.
+   *
+   * @todo https://www.drupal.org/node/2822663 Make this protected.
+   *
+   * @var \Drupal\migrate\MigrateMessageInterface
+   */
+  public $message;
+
+  /**
+   * Constructs a MigrateExecutable and verifies and sets the memory limit.
+   *
+   * @param \Drupal\migrate\Plugin\MigrationInterface $migration
+   *   The migration to run.
+   * @param \Drupal\migrate\MigrateMessageInterface $message
+   *   (optional) The migrate message service.
+   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   *   (optional) The event dispatcher.
+   *
+   * @throws \Drupal\migrate\MigrateException
+   */
+  public function __construct(MigrationInterface $migration, MigrateMessageInterface $message = NULL, EventDispatcherInterface $event_dispatcher = NULL) {
+    $this->migration = $migration;
+    $this->message = $message ?: new MigrateMessage();
+    $this->migration->getIdMap()->setMessage($this->message);
+    $this->eventDispatcher = $event_dispatcher;
+    // Record the memory limit in bytes
+    $limit = trim(ini_get('memory_limit'));
+    if ($limit == '-1') {
+      $this->memoryLimit = PHP_INT_MAX;
+    }
+    else {
+      $this->memoryLimit = Bytes::toInt($limit);
+    }
+  }
+
+  /**
+   * Returns the source.
+   *
+   * Makes sure source is initialized based on migration settings.
+   *
+   * @return \Drupal\migrate\Plugin\MigrateSourceInterface
+   *   The source.
+   */
+  protected function getSource() {
+    if (!isset($this->source)) {
+      $this->source = $this->migration->getSourcePlugin();
+    }
+    return $this->source;
+  }
+
+  /**
+   * Gets the event dispatcher.
+   *
+   * @return \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   */
+  protected function getEventDispatcher() {
+    if (!$this->eventDispatcher) {
+      $this->eventDispatcher = \Drupal::service('event_dispatcher');
+    }
+    return $this->eventDispatcher;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function import() {
+    // Only begin the import operation if the migration is currently idle.
+    if ($this->migration->getStatus() !== MigrationInterface::STATUS_IDLE) {
+      $this->message->display($this->t('Migration @id is busy with another operation: @status',
+        [
+          '@id' => $this->migration->id(),
+          '@status' => $this->t($this->migration->getStatusLabel()),
+        ]), 'error');
+      return MigrationInterface::RESULT_FAILED;
+    }
+    $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_IMPORT, new MigrateImportEvent($this->migration, $this->message));
+
+    // Knock off migration if the requirements haven't been met.
+    try {
+      $this->migration->checkRequirements();
+    }
+    catch (RequirementsException $e) {
+      $this->message->display(
+        $this->t(
+          'Migration @id did not meet the requirements. @message @requirements',
+          [
+            '@id' => $this->migration->id(),
+            '@message' => $e->getMessage(),
+            '@requirements' => $e->getRequirementsString(),
+          ]
+        ),
+        'error'
+      );
+
+      return MigrationInterface::RESULT_FAILED;
+    }
+
+    $this->migration->setStatus(MigrationInterface::STATUS_IMPORTING);
+    $return = MigrationInterface::RESULT_COMPLETED;
+    $source = $this->getSource();
+    $id_map = $this->migration->getIdMap();
+
+    try {
+      $source->rewind();
+    }
+    catch (\Exception $e) {
+      $this->message->display(
+        $this->t('Migration failed with source plugin exception: @e', ['@e' => $e->getMessage()]), 'error');
+      $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
+      return MigrationInterface::RESULT_FAILED;
+    }
+
+    $destination = $this->migration->getDestinationPlugin();
+    while ($source->valid()) {
+      $row = $source->current();
+      $this->sourceIdValues = $row->getSourceIdValues();
+
+      try {
+        $this->processRow($row);
+        $save = TRUE;
+      }
+      catch (MigrateException $e) {
+        $this->migration->getIdMap()->saveIdMapping($row, [], $e->getStatus());
+        $this->saveMessage($e->getMessage(), $e->getLevel());
+        $save = FALSE;
+      }
+      catch (MigrateSkipRowException $e) {
+        if ($e->getSaveToMap()) {
+          $id_map->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_IGNORED);
+        }
+        if ($message = trim($e->getMessage())) {
+          $this->saveMessage($message, MigrationInterface::MESSAGE_INFORMATIONAL);
+        }
+        $save = FALSE;
+      }
+
+      if ($save) {
+        try {
+          $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_ROW_SAVE, new MigratePreRowSaveEvent($this->migration, $this->message, $row));
+          $destination_id_values = $destination->import($row, $id_map->lookupDestinationId($this->sourceIdValues));
+          $this->getEventDispatcher()->dispatch(MigrateEvents::POST_ROW_SAVE, new MigratePostRowSaveEvent($this->migration, $this->message, $row, $destination_id_values));
+          if ($destination_id_values) {
+            // We do not save an idMap entry for config.
+            if ($destination_id_values !== TRUE) {
+              $id_map->saveIdMapping($row, $destination_id_values, $this->sourceRowStatus, $destination->rollbackAction());
+            }
+          }
+          else {
+            $id_map->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_FAILED);
+            if (!$id_map->messageCount()) {
+              $message = $this->t('New object was not saved, no error provided');
+              $this->saveMessage($message);
+              $this->message->display($message);
+            }
+          }
+        }
+        catch (MigrateException $e) {
+          $this->migration->getIdMap()->saveIdMapping($row, [], $e->getStatus());
+          $this->saveMessage($e->getMessage(), $e->getLevel());
+        }
+        catch (\Exception $e) {
+          $this->migration->getIdMap()->saveIdMapping($row, [], MigrateIdMapInterface::STATUS_FAILED);
+          $this->handleException($e);
+        }
+      }
+
+      $this->sourceRowStatus = MigrateIdMapInterface::STATUS_IMPORTED;
+
+      // Check for memory exhaustion.
+      if (($return = $this->checkStatus()) != MigrationInterface::RESULT_COMPLETED) {
+        break;
+      }
+
+      // If anyone has requested we stop, return the requested result.
+      if ($this->migration->getStatus() == MigrationInterface::STATUS_STOPPING) {
+        $return = $this->migration->getInterruptionResult();
+        $this->migration->clearInterruptionResult();
+        break;
+      }
+
+      try {
+        $source->next();
+      }
+      catch (\Exception $e) {
+        $this->message->display(
+          $this->t('Migration failed with source plugin exception: @e',
+            ['@e' => $e->getMessage()]), 'error');
+        $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
+        return MigrationInterface::RESULT_FAILED;
+      }
+    }
+
+    $this->getEventDispatcher()->dispatch(MigrateEvents::POST_IMPORT, new MigrateImportEvent($this->migration, $this->message));
+    $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
+    return $return;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function rollback() {
+    // Only begin the rollback operation if the migration is currently idle.
+    if ($this->migration->getStatus() !== MigrationInterface::STATUS_IDLE) {
+      $this->message->display($this->t('Migration @id is busy with another operation: @status', ['@id' => $this->migration->id(), '@status' => $this->t($this->migration->getStatusLabel())]), 'error');
+      return MigrationInterface::RESULT_FAILED;
+    }
+
+    // Announce that rollback is about to happen.
+    $this->getEventDispatcher()->dispatch(MigrateEvents::PRE_ROLLBACK, new MigrateRollbackEvent($this->migration));
+
+    // Optimistically assume things are going to work out; if not, $return will be
+    // updated to some other status.
+    $return = MigrationInterface::RESULT_COMPLETED;
+
+    $this->migration->setStatus(MigrationInterface::STATUS_ROLLING_BACK);
+    $id_map = $this->migration->getIdMap();
+    $destination = $this->migration->getDestinationPlugin();
+
+    // Loop through each row in the map, and try to roll it back.
+    foreach ($id_map as $map_row) {
+      $destination_key = $id_map->currentDestination();
+      if ($destination_key) {
+        $map_row = $id_map->getRowByDestination($destination_key);
+        if ($map_row['rollback_action'] == MigrateIdMapInterface::ROLLBACK_DELETE) {
+          $this->getEventDispatcher()
+            ->dispatch(MigrateEvents::PRE_ROW_DELETE, new MigrateRowDeleteEvent($this->migration, $destination_key));
+          $destination->rollback($destination_key);
+          $this->getEventDispatcher()
+            ->dispatch(MigrateEvents::POST_ROW_DELETE, new MigrateRowDeleteEvent($this->migration, $destination_key));
+        }
+        // We're now done with this row, so remove it from the map.
+        $id_map->deleteDestination($destination_key);
+      }
+      else {
+        // If there is no destination key the import probably failed and we can
+        // remove the row without further action.
+        $source_key = $id_map->currentSource();
+        $id_map->delete($source_key);
+      }
+
+      // Check for memory exhaustion.
+      if (($return = $this->checkStatus()) != MigrationInterface::RESULT_COMPLETED) {
+        break;
+      }
+
+      // If anyone has requested we stop, return the requested result.
+      if ($this->migration->getStatus() == MigrationInterface::STATUS_STOPPING) {
+        $return = $this->migration->getInterruptionResult();
+        $this->migration->clearInterruptionResult();
+        break;
+      }
+    }
+
+    // Notify modules that rollback attempt was complete.
+    $this->getEventDispatcher()->dispatch(MigrateEvents::POST_ROLLBACK, new MigrateRollbackEvent($this->migration));
+    $this->migration->setStatus(MigrationInterface::STATUS_IDLE);
+
+    return $return;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processRow(Row $row, array $process = NULL, $value = NULL) {
+    foreach ($this->migration->getProcessPlugins($process) as $destination => $plugins) {
+      $multiple = FALSE;
+      /** @var $plugin \Drupal\migrate\Plugin\MigrateProcessInterface */
+      foreach ($plugins as $plugin) {
+        $definition = $plugin->getPluginDefinition();
+        // Many plugins expect a scalar value but the current value of the
+        // pipeline might be multiple scalars (this is set by the previous
+        // plugin) and in this case the current value needs to be iterated
+        // and each scalar separately transformed.
+        if ($multiple && !$definition['handle_multiples']) {
+          $new_value = [];
+          if (!is_array($value)) {
+            throw new MigrateException(sprintf('Pipeline failed at %s plugin for destination %s: %s received instead of an array,', $plugin->getPluginId(), $destination, $value));
+          }
+          $break = FALSE;
+          foreach ($value as $scalar_value) {
+            try {
+              $new_value[] = $plugin->transform($scalar_value, $this, $row, $destination);
+            }
+            catch (MigrateSkipProcessException $e) {
+              $new_value[] = NULL;
+              $break = TRUE;
+            }
+          }
+          $value = $new_value;
+          if ($break) {
+            break;
+          }
+        }
+        else {
+          try {
+            $value = $plugin->transform($value, $this, $row, $destination);
+          }
+          catch (MigrateSkipProcessException $e) {
+            $value = NULL;
+            break;
+          }
+          $multiple = $plugin->multiple();
+        }
+      }
+      // Ensure all values, including nulls, are migrated.
+      if ($plugins) {
+        if (isset($value)) {
+          $row->setDestinationProperty($destination, $value);
+        }
+        else {
+          $row->setEmptyDestinationProperty($destination);
+        }
+      }
+      // Reset the value.
+      $value = NULL;
+    }
+  }
+
+  /**
+   * Fetches the key array for the current source record.
+   *
+   * @return array
+   *   The current source IDs.
+   */
+  protected function currentSourceIds() {
+    return $this->getSource()->getCurrentIds();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function saveMessage($message, $level = MigrationInterface::MESSAGE_ERROR) {
+    $this->migration->getIdMap()->saveMessage($this->sourceIdValues, $message, $level);
+  }
+
+  /**
+   * Takes an Exception object and both saves and displays it.
+   *
+   * Pulls in additional information on the location triggering the exception.
+   *
+   * @param \Exception $exception
+   *   Object representing the exception.
+   * @param bool $save
+   *   (optional) Whether to save the message in the migration's mapping table.
+   *   Set to FALSE in contexts where this doesn't make sense.
+   */
+  protected function handleException(\Exception $exception, $save = TRUE) {
+    $result = Error::decodeException($exception);
+    $message = $result['@message'] . ' (' . $result['%file'] . ':' . $result['%line'] . ')';
+    if ($save) {
+      $this->saveMessage($message);
+    }
+    $this->message->display($message, 'error');
+  }
+
+  /**
+   * Checks for exceptional conditions, and display feedback.
+   */
+  protected function checkStatus() {
+    if ($this->memoryExceeded()) {
+      return MigrationInterface::RESULT_INCOMPLETE;
+    }
+    return MigrationInterface::RESULT_COMPLETED;
+  }
+
+  /**
+   * Tests whether we've exceeded the desired memory threshold.
+   *
+   * If so, output a message.
+   *
+   * @return bool
+   *   TRUE if the threshold is exceeded, otherwise FALSE.
+   */
+  protected function memoryExceeded() {
+    $usage = $this->getMemoryUsage();
+    $pct_memory = $usage / $this->memoryLimit;
+    if (!$threshold = $this->memoryThreshold) {
+      return FALSE;
+    }
+    if ($pct_memory > $threshold) {
+      $this->message->display(
+        $this->t(
+          'Memory usage is @usage (@pct% of limit @limit), reclaiming memory.',
+          [
+            '@pct' => round($pct_memory * 100),
+            '@usage' => $this->formatSize($usage),
+            '@limit' => $this->formatSize($this->memoryLimit),
+          ]
+        ),
+        'warning'
+      );
+      $usage = $this->attemptMemoryReclaim();
+      $pct_memory = $usage / $this->memoryLimit;
+      // Use a lower threshold - we don't want to be in a situation where we keep
+      // coming back here and trimming a tiny amount
+      if ($pct_memory > (0.90 * $threshold)) {
+        $this->message->display(
+          $this->t(
+            'Memory usage is now @usage (@pct% of limit @limit), not enough reclaimed, starting new batch',
+            [
+              '@pct' => round($pct_memory * 100),
+              '@usage' => $this->formatSize($usage),
+              '@limit' => $this->formatSize($this->memoryLimit),
+            ]
+          ),
+          'warning'
+        );
+        return TRUE;
+      }
+      else {
+        $this->message->display(
+          $this->t(
+            'Memory usage is now @usage (@pct% of limit @limit), reclaimed enough, continuing',
+            [
+              '@pct' => round($pct_memory * 100),
+              '@usage' => $this->formatSize($usage),
+              '@limit' => $this->formatSize($this->memoryLimit),
+            ]
+          ),
+          'warning');
+        return FALSE;
+      }
+    }
+    else {
+      return FALSE;
+    }
+  }
+
+  /**
+   * Returns the memory usage so far.
+   *
+   * @return int
+   *   The memory usage.
+   */
+  protected function getMemoryUsage() {
+    return memory_get_usage();
+  }
+
+  /**
+   * Tries to reclaim memory.
+   *
+   * @return int
+   *   The memory usage after reclaim.
+   */
+  protected function attemptMemoryReclaim() {
+    // First, try resetting Drupal's static storage - this frequently releases
+    // plenty of memory to continue.
+    drupal_static_reset();
+
+    // Entity storage can blow up with caches so clear them out.
+    $manager = \Drupal::entityManager();
+    foreach ($manager->getDefinitions() as $id => $definition) {
+      $manager->getStorage($id)->resetCache();
+    }
+
+    // @TODO: explore resetting the container.
+
+    // Run garbage collector to further reduce memory.
+    gc_collect_cycles();
+
+    return memory_get_usage();
+  }
+
+  /**
+   * Generates a string representation for the given byte count.
+   *
+   * @param int $size
+   *   A size in bytes.
+   *
+   * @return string
+   *   A translated string representation of the size.
+   */
+  protected function formatSize($size) {
+    return format_size($size);
+  }
+
+}