module ActiveModel::Serializer::Caching::ClassMethods

def digest_caller_file(caller_line)
  serializer_file_path = caller_line[CALLER_FILE]
  serializer_file_contents = IO.read(serializer_file_path)
  algorithm = ActiveModelSerializers.config.use_sha1_digests ? Digest::SHA1 : Digest::MD5
  algorithm.hexdigest(serializer_file_contents)
rescue TypeError, Errno::ENOENT
  warn <<-EOF.strip_heredoc
    Cannot digest non-existent file: '#{caller_line}'.
    Please set `::_cache_digest` of the serializer
    if you'd like to cache it.
    EOF
  ''.freeze
end