1# frozen_string_literal: true 2 3# Provides a way to work around Rails issue where dependent objects are all 4# loaded into memory before destroyed: https://github.com/rails/rails/issues/22510. 5# 6# This concern allows an ActiveRecord module to destroy all its dependent 7# associations in batches. The idea is borrowed from https://github.com/thisismydesign/batch_dependent_associations. 8# 9# The differences here with that gem: 10# 11# 1. We allow excluding certain associations. 12# 2. We don't need to support delete_all since we can use the EachBatch concern. 13module BatchDestroyDependentAssociations 14 extend ActiveSupport::Concern 15 16 DEPENDENT_ASSOCIATIONS_BATCH_SIZE = 1000 17 18 def dependent_associations_to_destroy 19 self.class.reflect_on_all_associations(:has_many).select { |assoc| assoc.options[:dependent] == :destroy } 20 end 21 22 def destroy_dependent_associations_in_batches(exclude: []) 23 dependent_associations_to_destroy.each do |association| 24 next if exclude.include?(association.name) 25 26 # rubocop:disable GitlabSecurity/PublicSend 27 public_send(association.name).find_each(batch_size: DEPENDENT_ASSOCIATIONS_BATCH_SIZE, &:destroy) 28 end 29 end 30end 31