class EmptySource in Drupal 8

Source returning a row based on the constants provided.

Example:

source:
  plugin: empty
  constants:
    entity_type: user
    field_name: image

This will return a single row containing 'entity_type' and 'field_name' elements, with values of 'user' and 'image', respectively.

Plugin annotation

@MigrateSource(
  id = "empty",
  source_module = "migrate"
)

Hierarchy

• class \Drupal\Component\Plugin\PluginBase implements DerivativeInspectionInterface, PluginInspectionInterface
  • class \Drupal\Core\Plugin\PluginBase uses DependencySerializationTrait, MessengerTrait, StringTranslationTrait
    • class \Drupal\migrate\Plugin\migrate\source\SourcePluginBase implements RollbackAwareInterface, MigrateSourceInterface
      • class \Drupal\migrate\Plugin\migrate\source\EmptySource

1 file declares its use of EmptySource

EmptySource.php in core/modules/migrate_drupal/src/Plugin/migrate/source/EmptySource.php

File

core/modules/migrate/src/Plugin/migrate/source/EmptySource.php, line 26

Namespace

Drupal\migrate\Plugin\migrate\source

class EmptySource extends SourcePluginBase {

  /**
   * {@inheritdoc}
   */
  public function fields() {
    return [
      'id' => t('ID'),
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function initializeIterator() {
    return new \ArrayIterator([
      [
        'id' => '',
      ],
    ]);
  }

  /**
   * Allows class to decide how it will react when it is treated like a string.
   */
  public function __toString() {
    return '';
  }

  /**
   * {@inheritdoc}
   */
  public function getIds() {
    $ids['id']['type'] = 'string';
    return $ids;
  }

  /**
   * {@inheritdoc}
   */
  public function count($refresh = FALSE) {
    return 1;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DependencySerializationTrait::$_entityStorages	protected	property	An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds	protected	property	An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep	public	function		1
DependencySerializationTrait::__wakeup	public	function		2
EmptySource::count	public	function	Gets the source count. Overrides SourcePluginBase::count
EmptySource::fields	public	function	Returns available fields on the source. Overrides MigrateSourceInterface::fields
EmptySource::getIds	public	function	Defines the source fields uniquely identifying a source row. Overrides MigrateSourceInterface::getIds
EmptySource::initializeIterator	public	function	Initializes the iterator with the source data. Overrides SourcePluginBase::initializeIterator
EmptySource::__toString	public	function	Allows class to decide how it will react when it is treated like a string. Overrides MigrateSourceInterface::__toString
MessengerTrait::$messenger	protected	property	The messenger.	29
MessengerTrait::messenger	public	function	Gets the messenger.	29
MessengerTrait::setMessenger	public	function	Sets the messenger.
PluginBase::$configuration	protected	property	Configuration information passed into the plugin.	1
PluginBase::$pluginDefinition	protected	property	The plugin implementation definition.	1
PluginBase::$pluginId	protected	property	The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR		constant	A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId	public	function	Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId	public	function	Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginDefinition	public	function	Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition	3
PluginBase::getPluginId	public	function	Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable	public	function	Determines if the plugin is configurable.
SourcePluginBase::$cache	protected	property	The backend cache.
SourcePluginBase::$cacheCounts	protected	property	Whether this instance should cache the source count.	1
SourcePluginBase::$cacheKey	protected	property	Key to use for caching counts.
SourcePluginBase::$currentRow	protected	property	The current row from the query.
SourcePluginBase::$currentSourceIds	protected	property	The primary key of the current row.
SourcePluginBase::$highWaterProperty	protected	property	Information on the property used as the high-water mark.
SourcePluginBase::$highWaterStorage	protected	property	The key-value storage for the high-water value.
SourcePluginBase::$idMap	protected	property	The migration ID map.
SourcePluginBase::$iterator	protected	property	The iterator to iterate over the source rows.
SourcePluginBase::$mapRowAdded	protected	property	Flags whether source plugin will read the map row and add to data row.
SourcePluginBase::$migration	protected	property	The entity migration object.
SourcePluginBase::$moduleHandler	protected	property	The module handler service.	2
SourcePluginBase::$originalHighWater	protected	property	The high water mark at the beginning of the import operation.
SourcePluginBase::$skipCount	protected	property	Whether this instance should not attempt to count the source.	1
SourcePluginBase::$trackChanges	protected	property	Flags whether to track changes to incoming data.	1
SourcePluginBase::aboveHighwater	protected	function	Check if the incoming data is newer than what we've previously imported.
SourcePluginBase::current	public	function
SourcePluginBase::doCount	protected	function	Gets the source count checking if the source is countable or using the iterator_count function.	1
SourcePluginBase::fetchNextRow	protected	function	Position the iterator to the following row.	1
SourcePluginBase::getCache	protected	function	Gets the cache object.
SourcePluginBase::getCurrentIds	public	function	Gets the currentSourceIds data member.
SourcePluginBase::getHighWater	protected	function	The current value of the high water mark.
SourcePluginBase::getHighWaterField	protected	function	Get the name of the field used as the high watermark.
SourcePluginBase::getHighWaterProperty	protected	function	Get information on the property used as the high watermark.
SourcePluginBase::getHighWaterStorage	protected	function	Get the high water storage object.	1
SourcePluginBase::getIterator	protected	function	Returns the iterator that will yield the row arrays to be processed.
SourcePluginBase::getModuleHandler	protected	function	Gets the module handler.
SourcePluginBase::getSourceModule	public	function	Gets the source module providing the source data. Overrides MigrateSourceInterface::getSourceModule
SourcePluginBase::key	public	function	Gets the iterator key.
SourcePluginBase::next	public	function	The migration iterates over rows returned by the source plugin. This method determines the next row which will be processed and imported into the system.
SourcePluginBase::postRollback	public	function	Performs post-rollback tasks. Overrides RollbackAwareInterface::postRollback
SourcePluginBase::prepareRow	public	function	Adds additional data to the row. Overrides MigrateSourceInterface::prepareRow	50
SourcePluginBase::preRollback	public	function	Performs pre-rollback tasks. Overrides RollbackAwareInterface::preRollback
SourcePluginBase::rewind	public	function	Rewinds the iterator.
SourcePluginBase::rowChanged	protected	function	Checks if the incoming row has changed since our last import.
SourcePluginBase::saveHighWater	protected	function	Save the new high water mark.
SourcePluginBase::valid	public	function	Checks whether the iterator is currently valid.
SourcePluginBase::__construct	public	function	Constructs a \Drupal\Component\Plugin\PluginBase object. Overrides PluginBase::__construct	4
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	1
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.