diff options
Diffstat (limited to 'lib/gitlab/safe_request_loader.rb')
-rw-r--r-- | lib/gitlab/safe_request_loader.rb | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/lib/gitlab/safe_request_loader.rb b/lib/gitlab/safe_request_loader.rb new file mode 100644 index 00000000000..89eca16c272 --- /dev/null +++ b/lib/gitlab/safe_request_loader.rb @@ -0,0 +1,55 @@ +# frozen_string_literal: true + +module Gitlab + class SafeRequestLoader + def self.execute(args, &block) + new(**args).execute(&block) + end + + def initialize(resource_key:, resource_ids:, default_value: nil) + @resource_key = resource_key + @resource_ids = resource_ids.uniq + @default_value = default_value + @resource_data = {} + end + + def execute(&block) + raise ArgumentError, 'Block is mandatory' unless block_given? + + load_resource_data + remove_loaded_resource_ids + + update_resource_data(&block) + + resource_data + end + + private + + attr_reader :resource_key, :resource_ids, :default_value, :resource_data, :missing_resource_ids + + def load_resource_data + @resource_data = Gitlab::SafeRequestStore.fetch(resource_key) { resource_data } + end + + def remove_loaded_resource_ids + # Look up only the IDs we need + @missing_resource_ids = resource_ids - resource_data.keys + end + + def update_resource_data(&block) + return if missing_resource_ids.blank? + + reloaded_resource_data = yield(missing_resource_ids) + + @resource_data.merge!(reloaded_resource_data) + + mark_absent_values + end + + def mark_absent_values + absent = (missing_resource_ids - resource_data.keys).to_h { [_1, default_value] } + @resource_data.merge!(absent) + end + end +end |