call

# File actionpack/lib/action_dispatch/middleware/public_exceptions.rb, line 21
    def call(env)
      request      = ActionDispatch::Request.new(env)
      status       = request.path_info[1..-1].to_i
      begin
        content_type = request.formats.first
      rescue Mime::Type::InvalidMimeType
        content_type = Mime[:text]
      end
      body = { status: status, error: Rack::Utils::HTTP_STATUS_CODES.fetch(status, Rack::Utils::HTTP_STATUS_CODES[500]) }

      render(status, content_type, body)
    end