--- /dev/null
+<?php
+
+namespace Drupal\migrate_plus\Event;
+
+/**
+ * Defines the row preparation event for the migration system.
+ *
+ * @see \Drupal\migrate\Event\MigratePrepareRowEvent
+ */
+final class MigrateEvents {
+
+ /**
+ * Name of the event fired when preparing a source data row.
+ *
+ * This event allows modules to perform an action whenever the source plugin
+ * has read the inital source data into a Row object. Typically, this would be
+ * used to add data to the row, manipulate the data into a canonical form, or
+ * signal by exception that the row should be skipped. The event listener
+ * method receives a \Drupal\migrate_plus\Event\MigratePrepareRowEvent instance.
+ *
+ * @Event
+ *
+ * @see \Drupal\migrate_plus\Event\MigratePrepareRowEvent
+ *
+ * @var string
+ */
+ const PREPARE_ROW = 'migrate_plus.prepare_row';
+
+}