Migrating Content into Drupal 8
November 28th, 2014
Keith Dechant

Drupal 8 includes a powerful built-in migration system for importing content into your site. It is designed to handle data from Drupal 6 or 7, and much more. It is built around a plugin-based architecture, which allows importing of data from any external data source if you write your own source plugin.

History

When Drupal 7 was released, it came with an upgrade script that would convert a Drupal 6 database into a Drupal 7 database. For Drupal 8, the core team decided against this approach, in favor of creating a more flexible migration module.

Also, Drupal 7 has the Migrate and Migrate D2D contrib modules, used for importing data into a Drupal 7 database. This effort has been moved into Core in Drupal 8.

The team developing the Migrate modules maintains a group on Drupal.org. For more information about the status of these modules, visit the IMP project on Drupal.org.

Migrations in Core

Drupal 8 includes two core modules:

Migrate - A base module for creating your own custom migrations. This module provides the core migration architecture, but does not define any usable migrations itself.

Migrate Drupal, a module containing migration definitions and source plugins for migrating content from Drupal 6 to Drupal 8. This will eventually support Drupal 7 as well.

Other components

The Migrate and Migrate Drupal modules do not currently provide a UI for running migrations. You will need an external component to run migrations.

Drush You can create a migration manifest (a YAML file) and execute it using the "drush migrate-manifest" command. Drush 7 is required.

Note: The previous Drush command, "drush migrate-import", used with the Drupal 7 Migrate module, has been removed from Drupal 8.

Also note: As of Drupal 8 beta 2, the "drush migrate-manifest" command does not work with managed files, because it does not yet have a parameter for specifying the source directory where the files should be copied from.

Migrate Upgrade - A contrib module which provides a user interface for migrations. As of this writing, the module is still under development.

Migrating from Drupal 6

The Migrate Drupal module is being built to help with migrating from Drupal 6/7 to Drupal 8. Its aim is to import many components of Drupal like content types, fields, users, nodes, and more.

Migrate Drupal comes out-of-the-box with many of these migrations already built. It can even query CCK to determine the list of available fields to use when importing field data. To run these built-in migrations, you simply need to define a migration manifest. The following example would import Drupal 6 users and taxonomies:

- d6_user
- d6_taxonomy_vocabulary
- d6_taxonomy_term

To run the migration, open a command prompt and run the following command:

drush migrate-manifest manifest.yml --legacy-db-url=mysql://{dbuser}:{dbpass}@localhost/{dbname}

Replace {dbuser}, {dbpass}, and {dbname} with the MySQL username, password, and database name for your Drupal 6 database.

Migrating from Drupal 7

The Migrate Drupal module in Drupal 8 beta 3 does not yet include support for migrating from Drupal 7. Developers migrating from Drupal 7 to 8 will need to write their own custom migration scripts or pursue other options.

At the 2014 Pacific Northwest Drupal Summit, several presenters and participants mentioned that the Drupal 7-8 migration path is not expected to be completed by the release of Drupal 8.0.0. It is expected that this will be completed in a future core release.

For an example of writing a custom migration from Drupal 7 to Drupal 8, see the next installment in this series, Migrating Users from Drupal 7.