Module: SecondLevelCache::ActiveRecord::Associations::Preloader::BelongsTo

Defined in:
lib/second_level_cache/active_record/preloader.rb

Instance Method Summary collapse

Instance Method Details

#records_for(ids, &block) ⇒ Object 



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# File 'lib/second_level_cache/active_record/preloader.rb', line 8

def records_for(ids, &block)
  return super(ids, &block) unless reflection.is_a?(::ActiveRecord::Reflection::BelongsToReflection)
  return super(ids, &block) unless klass.second_level_cache_enabled?

  map_cache_keys = ids.map { |id| klass.second_level_cache_key(id) }
  records_from_cache = ::SecondLevelCache.cache_store.read_multi(*map_cache_keys)
  # NOTICE
  # Rails.cache.read_multi return hash that has keys only hitted.
  # eg. Rails.cache.read_multi(1,2,3) => {2 => hit_value, 3 => hit_value}
  hitted_ids = records_from_cache.map { |key, _| key.split("/")[2] }
  missed_ids = ids.map(&:to_s) - hitted_ids

  ::SecondLevelCache.logger.info "missed ids -> #{missed_ids.join(',')} | hitted ids -> #{hitted_ids.join(',')}"

  record_marshals = RecordMarshal.load_multi(records_from_cache.values)

  if missed_ids.empty?
    return SecondLevelCache::RecordRelation.new(record_marshals)
  end

  records_from_db = super(missed_ids, &block)
  records_from_db.map do |r|
    write_cache(r)
  end

  SecondLevelCache::RecordRelation.new(records_from_db + record_marshals)
end