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Use `#queue_background_migration_jobs_by_range_at_intervals`

db/post_migrate/20210518074332_schedule_disable_expiration_policies_linked_to_no_container_images.rb

@@ -10,19 +10,15 @@ class ScheduleDisableExpirationPoliciesLinkedToNoContainerImages < ActiveRecord:
   disable_ddl_transaction!
-  class ContainerExpirationPolicy < ActiveRecord::Base
-    include ::EachBatch
-
-    self.table_name = 'container_expiration_policies'
-  end
-
   def up
-    ContainerExpirationPolicy.where(enabled: true).each_batch(of: BATCH_SIZE) do |batch, index|
-      range = batch.pluck(Arel.sql('MIN(project_id)'), Arel.sql('MAX(project_id)')).first
-      delay = index * DELAY
-
-      migrate_in(delay.seconds, MIGRATION, range)
-    end
+    queue_background_migration_jobs_by_range_at_intervals(
+      define_batchable_model('container_expiration_policies').where(enabled: true),
+      MIGRATION,
+      DELAY,
+      batch_size: BATCH_SIZE,
+      track_jobs: true,
+      primary_column_name: :project_id
+    )
   end
   def down