generate_local_secret

# File railties/lib/rails/application/configuration.rb, line 632
        def generate_local_secret
          key_file = root.join("tmp/local_secret.txt")

          unless File.exist?(key_file)
            random_key = SecureRandom.hex(64)
            FileUtils.mkdir_p(key_file.dirname)
            File.binwrite(key_file, random_key)
          end

          File.binread(key_file)
        end