Understanding migration development in Drupal 8: Strategies and tools to see what's happening

Dan Montgomery, Palantir.net

Migrations in Drupal can be challenging for developers because the tools and strategies to get started and peer behind the curtain are different than those used in most backend development.

Who is this for?

This is an intermediate topic intended for developers who have a basic understanding of Drupal 8 concepts including plugins and the way entities and fields are used in Drupal to manage content.

How do you get started and where do you look?

This will cover the basic concepts of the migration system including configuration files, source, destination, and process plugins.

How do I know what's happening inside the black box?

This will also cover strategies for quick iteration by reloading configuration files, running migrations on sample data, and debugging with custom process plugins, print statements, and xdebug.

How do I test for regressions?

An introduction to Behat testing for migrations. See https://github.com/palantirnet/palantir-behat-extension.

Dan Montgomery
Senior Engineer and Technical Architect @ Palantir.net
Technical Architect with an interest in Drupal and frontend technologies like React. Outside of work I love playing board games and video games and trying out different craft hobbies.


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