Manage the manual running of migrations
Sometimes migrations have to be run on certain environments at certain times to avoid busy periods. This gem adds functionality to allow migrations to be added to the codebase and then actually executed on each environment manually. The migration will appear as normal in the schema_migrations table and will be reflected in development.
It's recommended that the time between merging the migration and running it on every environment is kept as short as possible, to avoid accidentally releasing new code that relies on the migration having run in every environment.
In your Gemfile:
gem "background_migrations", git: "https://github.com/dentally/background_migrations"
Within a migration:
class MyMigration < ActiveRecord::Migration[7.0]
include BackgroundMigrations
background_migration { Rails.env.production? }
This will run the migration as normal in every Rails environment except production. On production, it will treat the migration as run, add it to schema_migrations and also add it to the pending background migrations list. You can view the list of pending migrations using:
bundle exec rake background_migrations:list_pending_migrations
You can run a pending migration using:
bundle exec rake background_migrations:run_pending_migration[VERSION_NUMBER]
This has only been tested in applications with one database.
After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
The Gemfile contains the most recent version of Rails we care about. Older versions are stored in their own Gemfiles in the gemfiles directory. To test a previous version, eg 7.2:
BUNDLE_GEMFILE=gemfiles/activerecord72.gemfile bundle install
BUNDLE_GEMFILE=gemfiles/activerecord72.gemfile be rspec
Each version is tested on CI in the ci.yml file matrix. Ensure this is up to date when adding/removing Rails versions.
Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/background_migrations.
The gem is available as open source under the terms of the MIT License.