class BeerTerm in Migrate Plus 8.4

This is an example of a simple SQL-based source plugin.

Source plugins are classes which deliver source data to the processing pipeline. For SQL sources, the SqlBase class provides most of the functionality needed - for a specific migration, you are required to implement the three simple public methods you see below.

This annotation tells Drupal that the name of the MigrateSource plugin implemented by this class is "beer_term". This is the name that the migration configuration references with the source "plugin" key.

Plugin annotation

@MigrateSource(
  id = "beer_term"
)

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_example\Plugin\migrate\source\BeerTerm

File

migrate_example/src/Plugin/migrate/source/BeerTerm.php, line 23

Namespace

Drupal\migrate_example\Plugin\migrate\source

class BeerTerm extends SqlBase {

  /**
   * {@inheritdoc}
   */
  public function query() {

    // The most important part of a SQL source plugin is the SQL query to
    // retrieve the data to be imported. Note that the query is not executed
    // here - the migration process will control execution of the query. Also
    // note that it is constructed from a $this->select() call - this ensures
    // that the query is executed against the database configured for this
    // source plugin.
    $fields = [
      'style',
      'details',
      'style_parent',
      'region',
      'hoppiness',
    ];
    return $this
      ->select('migrate_example_beer_topic', 'met')
      ->fields('met', $fields)
      ->orderBy('style_parent', 'ASC');
  }

  /**
   * {@inheritdoc}
   */
  public function fields() {

    // This method simply documents the available source fields provided by the
    // source plugin, for use by front-end tools. It returns an array keyed by
    // field/column name, with the value being a translated string explaining
    // to humans what the field represents.
    $fields = [
      'style' => $this
        ->t('Beer style'),
      'details' => $this
        ->t('Style details'),
      'style_parent' => $this
        ->t('Parent style'),
      // These values are not currently migrated - it's OK to skip fields you
      // don't need.
      'region' => $this
        ->t('Region the style is associated with'),
      'hoppiness' => $this
        ->t('Hoppiness of the style'),
    ];
    return $fields;
  }

  /**
   * {@inheritdoc}
   */
  public function getIds() {

    // This method indicates what field(s) from the source row uniquely identify
    // that source row, and what their types are. This is critical information
    // for managing the migration. The keys of the returned array are the field
    // names from the query which comprise the unique identifier. The values are
    // arrays indicating the type of the field, used for creating compatible
    // columns in the map tables that track processed items.
    return [
      'style' => [
        'type' => 'string',
        // 'alias' is the alias for the table containing 'style' in the query
        // defined above. Optional in this case, but necessary if the same
        // column may occur in multiple tables in a join.
        'alias' => 'met',
      ],
    ];
  }

}

Members

Name	Modifiers	Type	Description	Overrides
BeerTerm::fields	public	function	Returns available fields on the source. Overrides MigrateSourceInterface::fields
BeerTerm::getIds	public	function	Defines the source fields uniquely identifying a source row. Overrides MigrateSourceInterface::getIds
BeerTerm::query	public	function	Overrides SqlBase::query
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
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::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.
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::checkRequirements	public	function	Checks if requirements for this plugin are OK. Overrides RequirementsInterface::checkRequirements	1
SqlBase::count	public	function	Gets the source count. Overrides SourcePluginBase::count	6
SqlBase::create	public static	function	Creates an instance of the plugin. Overrides ContainerFactoryPluginInterface::create	1
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::initializeIterator	protected	function	Initializes the iterator with the source data. Overrides SourcePluginBase::initializeIterator	20
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::__construct	public	function	Constructs a \Drupal\Component\Plugin\PluginBase object. Overrides SourcePluginBase::__construct	3
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.	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.