Why isn't express-js setting the Content-Type header?

Question

I have the following:

var express = require('express'),
    app = express.createServer();

app.get("/offline.manifest", function(req, res){
  res.contentType("text/cache-manifest");
  res.end("CACHE MANIFEST");
});

app.listen(8561);

The network tab in Chrome says it's text/plain. Why isn't it setting the header?

The code above works, my problems were caused by a linking to an old version of express-js

Ray Hulha · Accepted Answer · 2018-02-28T16:23:39.510

47

res.type('json') works too now and as others have said, you can simply use
res.json({your: 'object'})

edited Feb 28 '18 at 16:23

answered Oct 23 '16 at 20:43

Ray Hulha

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2

this is great since it still allows you to use `res.send(obj)` to send objects as JSON. Better than `res.end(JSON.stringify(obj))` – Joseph Nields Mar 17 '17 at 04:37
1

you can chain it too, `res.type('json').send({your: 'object'});` or as @danday74 below points out, simply `res.json({your: 'object'});` – Steve Kehlet Feb 27 '18 at 02:58

schaermu · Answer 2 · 2011-03-23T09:11:17.950

24

Try this code:

var express = require('express'),
    app = express.createServer();

app.get("/offline.manifest", function(req, res){
  res.header("Content-Type", "text/cache-manifest");
  res.end("CACHE MANIFEST");
});

app.listen(8561);

(I'm assuming you are using the latest release of express, 2.0.0)

UPDATE: I just did a quick test using Firefox 3.6.x and Live HTTP Headers. This is the addons output:

 HTTP/1.1 200 OK
 X-Powered-By: Express
 Content-Type: text/cache-manifest
 Connection: keep-alive
 Transfer-Encoding: chunked

Make sure you clear your cache before trying.

edited Mar 23 '11 at 09:11

answered Mar 23 '11 at 07:05

schaermu

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i just tested it on my local development setup, worked perfectly (see update) – schaermu Mar 23 '11 at 09:11
Aha! For some reason it was linking to an old version of node. Thank you! :) – Kit Sunde Mar 23 '11 at 09:35

score 2 · Answer 3 · answered Feb 05 '18 at 09:53

2

instead of res.send()

use res.json() which automatically sets the content-type to application/json

answered Feb 05 '18 at 09:53

danday74

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this doesn't remotely answer the question – sjmeverett May 15 '18 at 15:53
Not related to the question. – Ed Bishop Sep 30 '18 at 07:50
1

In my case, it was exactly the question : `Why isn't express-js setting the Content-Type header?` in my case to json. I learned about `res.json()` – ps0604 Jul 17 '20 at 20:19

Why isn't express-js setting the Content-Type header?

3 Answers3

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