Overview of migrate field plugins

Field plugins provide a direct upgrade solution from Drupal 6/7 fields to Drupal 8/9 equivalents.  They are responsible for handling the migration of custom fields and add processes to migrations for entities that have fields.

When you write custom migrate field plugins they:

• usually extend Drupal\migrate_drupal\Plugin\migrate\field\FieldPluginBase.
• must be annotated with \Drupal\migrate_drupal\Annotation\MigrateField.
• must be in the namespace sub directory Plugin\migrate\field under the namespace of the module that defines them, for example MYMODULE/src/Plugin/migrate/field.
• must have class names end with Field, otherwise they will not be detected.

List of core field plugins.

MigrateField example

The following example is the field plugin for Drupal 7 text fields.

@MigrateField(
  id = "d7_text",
  type_map = {
    "text" = "text",
    "text_long" = "text_long",
    "text_with_summary" = "text_with_summary"
  },
  core = {7},
  source_module = "text",
  destination_module = "text",
)

MigrateField annotation

• The id property often matches the source field type. It does not in this example.
• The  source_module is the name of the module on the source site that provides the field type.
• The  destination_module is the name of the module on the destination Drupal 8/9 that provides the field type.
• The core property is the Drupal version of the source site the provides the field type. If it the same for both Drupal 6 and Drupal 7 use {6, 7}.
• The 'type_map' is an array in the format 'd6/d7_field_name' => 'd8/d9_field_name'.