Node.js does not pipe contents

Question

I have a simple Web server, which should send a file. I took the code from another answer.

#! /usr/bin/node

const FS     = require ('fs');
const HTTP   = require ('http');

const server = HTTP.createServer ();

server.on ('request', (request, response) => {
  switch (request.url) {
  case '/':
    switch (request.method) {
    case 'GET':
      console.log ("GET /");
      let stat = FS.statSync ('index.html');
      console.log (stat.size);
      response.writeHead (200, { 'Content-Type': 'text/html',
                                 'Content-Lenght': stat.size });
      let index = FS.createReadStream ('index.html', 'UTF-8');
      index.pipe (response);
      response.end ();
      return;
    }
    break;
  }
  response.writeHead (400, {});
  response.end ();
});

server.listen (8080);

When I try to send a GET request with curl, I get no content. My server reports, that the index.html file has 324 bytes:

$ ./server.js 
GET /
324

But curl does not show the content. There header contains the content length, but the body is missing.

$ curl -v --noproxy \* http://localhost:8080/
[...]
* Connected to localhost (127.0.0.1) port 8080 (#0)
> GET / HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.64.0
> Accept: */*
> 
< HTTP/1.1 200 OK
< Content-Type: text/html
< Content-Lenght: 324
< Date: Sat, 21 Nov 2020 19:24:31 GMT
< Connection: keep-alive
< Transfer-Encoding: chunked
< 
* Connection #0 to host localhost left intact

I looks as if the connection got closed before the file has been piped. Is the the error and how can I avoid it?

Answer 1

Remove the response.end ();. You're prematurely closing the response BEFORE the .pipe() gets to do its work (it's asynchronous so it finishes over time and returns before it's done).

In the default configuration, .pipe() will end your response for you when it's done.

You will also notice that the other answer you took this idea from did not have a response.end().