Module Development

Write a Custom Migration for Drupal 8, 9, 10, and 11

Migration plugins are the glue that binds a source, a destination, and multiple process plugins together to move data from one place to another. Often referred to as migration templates, or simply migrations, migration plugins are YAML files that explain to Drupal where to get the data, how to process it, and where to save the resulting object.

Source, process, and destination plugins do the heavy lifting in each phase of the ETL process in a custom migration. We need to choose which plugins we want to use for each phase, as well as map fields from our source data to fields at our destination. A migration YAML file glues it all together and gives it a unique name that we can use to run it.

In this tutorial we'll:

  • Determine what information we're going to move, and where we're going to move it to
  • Install Migrate Plus and Migrate Tools which we'll use to run our custom migration
  • Write a custom migration plugin (configuration) YAML file that will work with Migrate Tools

By the end of this tutorial you should be able to write a custom migration YAML file and understand how to choose the source, destination, and process plugins that will do the work.