Rolling back a plugin migration

I’m working on a plugin (my first attempt at doing so).

The plugin requires extending the database with a new migration. I was able to run this initial migration using the bin/rake db:migrate command.

I noticed some problems with the migration afterwards, and am trying to rollback the database, then edit and re-run the migration.

However, when I run bin/rake db:rollback, I’m getting the following error:

rake aborted!
ActiveRecord::UnknownMigrationVersionError: 

No migration with version number 20210820205029.

The version number in the error message does correspond with the plugin migration I’m working on.

Any ideas?

2 Likes

Yeah, you can’t currently rollback migrations in plugin directories. The way I do it is move the migration to the core repo
mv plugins/discourse-example/db/migrate/20210823160357_migration.rb db/migrate/20210823160357_migration.rb

rollback, and then move it back to the plugin
mv db/migrate/20210823160357_migration.rb plugins/discourse-example/db/migrate/20210823160357_migration.rb

If your migration isn’t the last migration in the core db directory, you can use bin/rails db:migrate:down VERSION=20210823160357 to target the migration you just moved.

5 Likes

Nice lifehack, thanks!