Node.js: how to disable chunked transfer-encoding?

express, http-headers, node.js

Solution

Turns out this was actually a rather simple fix: setting the `transfer-encoding` header to an empty string in the response solved the problem:

...
res.oldWriteHead = res.writeHead;
res.writeHead = function(statusCode, reasonPhrase, headers) {
    res.header('Content-Length', contentLength);
    res.header('transfer-encoding', ''); // <-- add this line
    res.oldWriteHead(statusCode, reasonPhrase, headers);
}
...

The reason this works, is because after doing some digging, it appears the `transfer-encoding` header replaces `content-length` (since both can't co-exist). It just so happens that the clients I was using to test were choosing chunked transfer encoding over content length.

Problem

I'm missing a `content-length` header on my response from a Node server that I'm piping a .zip file from another location. I've injected a `content-length` header via the code below, but still it seems the `transfer-encoding: chunked` is overwriting it somehow. Response Headers ``` HTTP/1.1 200 OK access-control-allow-origin: * connection: close content-type: application/zip date: Mon, 14 Jul 2014 03:47:00 GMT etag: "\"eb939974703e14ee9f578642972ed984\"" last-modified: Sat, 12 Jul 2014 02:15:52 GMT server: Apache-Coyote/1.1 set-cookie: rememberMe=deleteMe; Path=/; Max-Age=0; Expires=Sun, 13-Jul-2014 03:47:00 GMT transfer-encoding: chunked X-Powered-By: Express ``` Code ``` var request = require('request'); var express = require('express'); var async = require('async'); var app = express(); app.get('/:bundle_id?', function(req, res) { var bundle_id = req.params.bundle_id; bundle_id = bundle_id.replace(/\.zip$/, ''); var url = "https://url....../bundles/" + bundle_id; async.waterfall([ function(callback) { request.get(url, function(req, res, data) { callback(null, JSON.parse(data).entities[0]['file-metadata']['content-length']); }); } ], function(err, contentLength) { request.get({ url: url, headers: { "Accept": "application/zip" } }).pipe(res); res.oldWriteHead = res.writeHead; res.writeHead = function(statusCode, reasonPhrase, headers) { res.header('Content-Length', contentLength); res.oldWriteHead(statusCode, reasonPhrase, headers); } }); }); app.listen(9000); ```

Original source