Sending multiple responses with the same response object in Express.js

Question

I have a long running process which needs to send data back at multiple stages. Is there some way to send back multiple responses with express.js

res.send(200, 'hello')
res.send(200, 'world')
res.end() 

but when I run curl -X POST localhost:3001/helloworld all I get is hello

How can I send multiple responses or is this not possible to do with express?

Answer 1

Use res.write().

res.send() already makes a call to res.end(), meaning you can't write to res anymore after a call to res.send (meaning also your res.end() call was useless).

EDIT: It is a Node.js internal function. See the documentation here

Answer 2

You can only send one HTTP response for one HTTP request. However, you can certainly write whatever kind of data in the response that you want. That could be newline-delimited JSON, multipart parts, or whatever other format you choose.

If you want to stream events from the server to the browser, an easy alternative might be to use something like Server-sent events (polyfill).

Answer 3

Try this, this should solve your problem.

app.get('/', function (req, res) {

  var i = 1,
    max = 5;

  //set the appropriate HTTP header
  res.setHeader('Content-Type', 'text/html');

  //send multiple responses to the client
  for (; i <= max; i++) {
    res.write('<h1>This is the response #: ' + i + '</h1>');
  }

  //end the response process
  res.end();
});