class Variable in Drupal 9

Drupal variable source from database.

This source class fetches variables from the source Drupal database. Depending on the configuration, this returns zero or a single row and as such is not a good example for any normal source class returning multiple rows.

Available configuration keys (one of which must be defined):

• variables: (optional) The list of variables to retrieve from the source database. Specified variables are retrieved in a single row.
• variables_no_row_if_missing: (optional) The list of variables to retrieve from the source database. If any of the variables listed here are missing in the source, then the source will return zero rows.

Examples:

With this configuration, the source will return one row even when the "filter_fallback_format" variable isn't available:

source:
  plugin: variable
  variables:
    - filter_fallback_format

With this configuration, the source will return one row if the variable is available, and zero if it isn't:

source:
  plugin: variable
  variables_no_row_if_missing:
    - filter_fallback_format

The variables and the variables_no_row_if_missing lists are always merged together. All of the following configurations are valid:

source:
  plugin: variable
  variables:
    - book_child_type
    - book_block_mode
    - book_allowed_types
  variables_no_row_if_missing:
    - book_child_type
    - book_block_mode
    - book_allowed_types

source:
  plugin: variable
  variables:
    - book_child_type
    - book_block_mode
  variables_no_row_if_missing:
    - book_allowed_types

source:
  plugin: variable
  variables_no_row_if_missing:
    - book_child_type
    - book_block_mode
    - book_allowed_types

For additional configuration keys, refer to the parent classes:

Plugin annotation

@MigrateSource(
  id = "variable",
  source_module = "system",
)

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\SqlBase implements ContainerFactoryPluginInterface, RequirementsInterface
        • class \Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase implements DependentPluginInterface uses DependencyTrait
          • class \Drupal\migrate_drupal\Plugin\migrate\source\Variable

See also

\Drupal\migrate\Plugin\migrate\source\SqlBase

\Drupal\migrate\Plugin\migrate\source\SourcePluginBase

4 files declare their use of Variable

ContactSettings.php in core/modules/contact/src/Plugin/migrate/source/ContactSettings.php

SearchPage.php in core/modules/search/src/Plugin/migrate/source/d6/SearchPage.php

SearchPage.php in core/modules/search/src/Plugin/migrate/source/d7/SearchPage.php

UpdateSettings.php in core/modules/update/src/Plugin/migrate/source/UpdateSettings.php

4 string references to 'Variable'

MultilingualReviewPageTest::getMissingPaths in core/modules/migrate_drupal_ui/tests/src/Functional/d7/MultilingualReviewPageTest.php

Gets the missing upgrade paths.

NoMultilingualReviewPageTest::getMissingPaths in core/modules/migrate_drupal_ui/tests/src/Functional/d7/NoMultilingualReviewPageTest.php

Gets the missing upgrade paths.

update.source.schema.yml in core/modules/update/config/schema/update.source.schema.yml

core/modules/update/config/schema/update.source.schema.yml

Upgrade7Test::getMissingPaths in core/modules/migrate_drupal_ui/tests/src/Functional/d7/Upgrade7Test.php

Gets the missing upgrade paths.

File

core/modules/migrate_drupal/src/Plugin/migrate/source/Variable.php, line 82

Namespace

Drupal\migrate_drupal\Plugin\migrate\source

class Variable extends DrupalSqlBase {

  /**
   * The variable names to fetch.
   *
   * @var array
   */
  protected $variables;

  /**
   * The variables that result in no row if any are missing from the source.
   *
   * @var array
   */
  protected $variablesNoRowIfMissing;

  /**
   * {@inheritdoc}
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration, StateInterface $state, EntityTypeManagerInterface $entity_type_manager) {
    parent::__construct($configuration, $plugin_id, $plugin_definition, $migration, $state, $entity_type_manager);
    $this->variablesNoRowIfMissing = $this->configuration['variables_no_row_if_missing'] ?? [];
    $variables = $this->configuration['variables'] ?? [];
    $this->variables = array_unique(array_merge(array_values($variables), array_values($this->variablesNoRowIfMissing)));
  }

  /**
   * {@inheritdoc}
   */
  protected function initializeIterator() {
    if ($this
      ->count()) {
      return new \ArrayIterator([
        $this
          ->values(),
      ]);
    }
    return new \ArrayIterator();
  }

  /**
   * Return the values of the variables specified in the plugin configuration.
   *
   * @return array
   *   An associative array where the keys are the variables specified in the
   *   plugin configuration and the values are the values found in the source.
   *   Only those values are returned that are actually in the database.
   */
  protected function values() {

    // Create an ID field so we can record migration in the map table.
    // Arbitrarily, use the first variable name.
    $values['id'] = reset($this->variables);
    return $values + array_map('unserialize', $this
      ->prepareQuery()
      ->execute()
      ->fetchAllKeyed());
  }

  /**
   * {@inheritdoc}
   */
  public function count($refresh = FALSE) {
    if (empty($this->variablesNoRowIfMissing)) {
      return 1;
    }
    $variable_names = array_keys($this
      ->query()
      ->execute()
      ->fetchAllAssoc('name'));
    if (!empty(array_diff($this->variablesNoRowIfMissing, $variable_names))) {
      return 0;
    }
    return 1;
  }

  /**
   * {@inheritdoc}
   */
  public function fields() {
    return array_combine($this->variables, $this->variables);
  }

  /**
   * {@inheritdoc}
   */
  public function query() {
    return $this
      ->getDatabase()
      ->select('variable', 'v')
      ->fields('v', [
      'name',
      'value',
    ])
      ->condition('name', $this->variables, 'IN');
  }

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

}

Members

Name	Modifiers	Type	Description	Overrides
DependencySerializationTrait::$_entityStorages	protected	property
DependencySerializationTrait::$_serviceIds	protected	property
DependencySerializationTrait::__wakeup	public	function		2
DependencyTrait::$dependencies	protected	property	The object's dependencies.
DependencyTrait::addDependencies	protected	function	Adds multiple dependencies.
DependencyTrait::addDependency	protected	function	Adds a dependency.
DrupalSqlBase::$entityTypeManager	protected	property	The entity type manager.
DrupalSqlBase::$requirements	protected	property	If the source provider is missing.
DrupalSqlBase::$systemData	protected	property	The contents of the system table.
DrupalSqlBase::calculateDependencies	public	function	Calculates dependencies for the configured plugin. Overrides DependentPluginInterface::calculateDependencies	1
DrupalSqlBase::checkRequirements	public	function	Checks if requirements for this plugin are OK. Overrides SqlBase::checkRequirements	4
DrupalSqlBase::create	public static	function	Creates an instance of the plugin. Overrides SqlBase::create	3
DrupalSqlBase::getModuleSchemaVersion	protected	function	Retrieves a module schema_version from the source Drupal database.
DrupalSqlBase::getSystemData	public	function	Retrieves all system data information from the source Drupal database.
DrupalSqlBase::moduleExists	protected	function	Checks if a given module is enabled in the source Drupal database.
DrupalSqlBase::variableGet	protected	function	Reads a variable from a source Drupal database.
MessengerTrait::$messenger	protected	property	The messenger.	27
MessengerTrait::messenger	public	function	Gets the messenger.	27
MessengerTrait::setMessenger	public	function	Sets the messenger.
MigrateSourceInterface::NOT_COUNTABLE		constant	Indicates that the source is not countable.
PluginBase::$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	2
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::$trackChanges	protected	property	Flags whether to track changes to incoming data.	1
SourcePluginBase::aboveHighwater	protected	function	Check if the incoming data is newer than what we've previously imported.
SourcePluginBase::current	public	function
SourcePluginBase::getCache	protected	function	Gets the cache object.
SourcePluginBase::getCurrentIds	public	function	Gets the currentSourceIds data member.
SourcePluginBase::getHighWater	protected	function	The current value of the high water mark.
SourcePluginBase::getHighWaterField	protected	function	Get the name of the field used as the high watermark.
SourcePluginBase::getHighWaterProperty	protected	function	Get information on the property used as the high watermark.
SourcePluginBase::getHighWaterStorage	protected	function	Get the high water storage object.
SourcePluginBase::getIterator	protected	function	Returns the iterator that will yield the row arrays to be processed.
SourcePluginBase::getModuleHandler	protected	function	Gets the module handler.
SourcePluginBase::getSourceModule	public	function	Gets the source module providing the source data. Overrides MigrateSourceInterface::getSourceModule
SourcePluginBase::key	public	function	Gets the iterator key.
SourcePluginBase::next	public	function
SourcePluginBase::postRollback	public	function	Performs post-rollback tasks. Overrides RollbackAwareInterface::postRollback
SourcePluginBase::prepareRow	public	function	Adds additional data to the row. Overrides MigrateSourceInterface::prepareRow	50
SourcePluginBase::preRollback	public	function	Performs pre-rollback tasks. Overrides RollbackAwareInterface::preRollback
SourcePluginBase::rewind	public	function	Rewinds the iterator.
SourcePluginBase::rowChanged	protected	function	Checks if the incoming row has changed since our last import.
SourcePluginBase::saveHighWater	protected	function	Save the new high water mark.
SourcePluginBase::valid	public	function	Checks whether the iterator is currently valid.
SqlBase::$batch	protected	property	The count of the number of batches run.
SqlBase::$batchSize	protected	property	Number of records to fetch from the database during each batch.
SqlBase::$database	protected	property	The database object.	1
SqlBase::$query	protected	property	The query string.
SqlBase::$state	protected	property	State service for retrieving database info.
SqlBase::doCount	protected	function	Gets the source count using countQuery(). Overrides SourcePluginBase::doCount
SqlBase::fetchNextBatch	protected	function	Prepares query for the next set of data from the source database.
SqlBase::fetchNextRow	protected	function	Position the iterator to the following row. Overrides SourcePluginBase::fetchNextRow
SqlBase::getDatabase	public	function	Gets the database connection object.	2
SqlBase::mapJoinable	protected	function	Checks if we can join against the map table.	1
SqlBase::prepareQuery	protected	function	Adds tags and metadata to the query.
SqlBase::select	protected	function	Wrapper for database select.
SqlBase::setUpDatabase	protected	function	Gets a connection to the referenced database.
SqlBase::__sleep	public	function	Overrides DependencySerializationTrait::__sleep
SqlBase::__toString	public	function	Prints the query string when the object is used as a string. Overrides MigrateSourceInterface::__toString
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	4
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.
Variable::$variables	protected	property	The variable names to fetch.
Variable::$variablesNoRowIfMissing	protected	property	The variables that result in no row if any are missing from the source.
Variable::count	public	function	Gets the source count. Overrides SourcePluginBase::count	1
Variable::fields	public	function	Returns available fields on the source. Overrides MigrateSourceInterface::fields	2
Variable::getIds	public	function	Defines the source fields uniquely identifying a source row. Overrides MigrateSourceInterface::getIds	2
Variable::initializeIterator	protected	function	Initializes the iterator with the source data. Overrides SqlBase::initializeIterator	2
Variable::query	public	function	Overrides SqlBase::query
Variable::values	protected	function	Return the values of the variables specified in the plugin configuration.	3
Variable::__construct	public	function	Constructs a \Drupal\Component\Plugin\PluginBase object. Overrides DrupalSqlBase::__construct