gitlab-org--gitlab-foss/app/models/concerns/batch_destroy_dependent_associations.rb
Stan Hu 760fdd1dd3 Fix project destruction failing due to idle in transaction timeouts
When deleting associated records, Rails loads all associations into memory
(https://github.com/rails/rails/issues/22510) before destroying them. This
can cause a surge in memory and cause destruction of objects to fail
due to idle in transaction database timeouts. This fix is inspired from
https://github.com/thisismydesign to destroy `has_many` relationships
in batches.

Closes #44610
2018-05-24 16:40:02 -07:00

28 lines
1.1 KiB
Ruby

# Provides a way to work around Rails issue where dependent objects are all
# loaded into memory before destroyed: https://github.com/rails/rails/issues/22510.
#
# This concern allows an ActiveRecord module to destroy all its dependent
# associations in batches. The idea is borrowed from https://github.com/thisismydesign/batch_dependent_associations.
#
# The differences here with that gem:
#
# 1. We allow excluding certain associations.
# 2. We don't need to support delete_all since we can use the EachBatch concern.
module BatchDestroyDependentAssociations
extend ActiveSupport::Concern
DEPENDENT_ASSOCIATIONS_BATCH_SIZE = 1000
def dependent_associations_to_destroy
self.class.reflect_on_all_associations(:has_many).select { |assoc| assoc.options[:dependent] == :destroy }
end
def destroy_dependent_associations_in_batches(exclude: [])
dependent_associations_to_destroy.each do |association|
next if exclude.include?(association.name)
# rubocop:disable GitlabSecurity/PublicSend
public_send(association.name).find_each(batch_size: DEPENDENT_ASSOCIATIONS_BATCH_SIZE, &:destroy)
end
end
end