gistfile1.js

function app(env) {
  var ostream = new MemoryStream();
  var times = 5;
  setTimeout(function t() {
    times--;
    ostream.write((new Date).toString())
    ostream.write("\n");
    if ( times <= 0 )
      ostream.close();
    else
      setTimeout(t, 1000);
  }, 1000);
  return { status: 200, headers: { 'Content-Type': 'text/plain' }, body: ostream };
}

// or, using a output stream set on env

function app(env) {
  var ostream = env["jsgi.output"];
  var times = 5;
  setTimeout(function t() {
    times--;
    ostream.write((new Date).toString())
    ostream.write("\n");
    if ( times <= 0 )
      ostream.close();
    else
      setTimeout(t, 1000);
  }, 1000);
  return { status: 200, headers: { 'Content-Type': 'text/plain' } };
}