gitlab-ce/lib/gitlab/graphql/loaders/batch_model_loader.rb

37 lines
1.2 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Graphql
module Loaders
class BatchModelLoader
attr_reader :model_class, :model_id, :preloads, :default_value
def initialize(model_class, model_id, preloads = nil, default_value: nil)
@model_class = model_class
@model_id = model_id
@preloads = preloads || []
@default_value = default_value
end
# rubocop: disable CodeReuse/ActiveRecord
def find
BatchLoader::GraphQL.for([model_id.to_i, preloads]).batch(key: model_class) do |for_params, loader, args|
model = args[:key]
keys_by_id = for_params.group_by(&:first)
ids = for_params.map(&:first)
preloads = for_params.flat_map(&:second).uniq
results = model.where(id: ids)
results = results.preload(*preloads) unless preloads.empty?
results = results.index_by(&:id)
keys_by_id.each do |id, keys|
keys.each { |k| loader.call(k, results[id] || default_value) }
end
end
end
# rubocop: enable CodeReuse/ActiveRecord
end
end
end
end