Rails abort if pending migrations with data

Readme.md

Abort if pending migrations with data

We use the awesome gem data-migrate with comes with a handy rake task to check if you have migrations pending. The task is really and extention to the task built in on rails but that also check for pending data migrations.

That rake task is available since version 6.3.0 of data-migrate. If you are stuck in an older version like I was here is a version of the rake task you can put in your project.

rake db:abort_if_pending_migrations:with_data

Kubernetes

You can use this rake task in an init container to halt your deployments until you migrations are ready.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-deployment
spec:
  template:
    spec:
      initContainers:
      - name: migrations-check
        image: my-rails-app
        args:
        - rake
        - db:abort_if_pending_migrations:with_data
      containers:
      - name: my-app
        image: my-rails-app
        ...

db_migrate_status_with_data.rake

namespace :db do
  namespace :abort_if_pending_migrations do
    task with_data: :environment do
      migrations_paths = DataMigrate::DataMigrator.migrations_paths
      data_migration_path = DataMigrate::DataMigrator.migrations_path
      migrations_paths.push data_migration_path

      if DataMigrate::DataMigrator.needs_migration?
        message = %{Run `rake db:migrate:with_data` to update your database then try again.}

        migrations = DataMigrate::DataMigrator.migrations_status migrations_paths
        migrations = migrations.select { |m| m[0] == 'down' }

        puts "You have #{migrations.size} pending migration#{migrations.size > 1 ? 's' : ''}:"
        migrations.each do |pending_migration|
          puts "  #{pending_migration[1]} #{pending_migration[2]}"
        end
        abort message
      end
    end
  end
end