Cannot gzip compress static files in Nodejs - node.js

Question

Gzipping static files does not work as required (as I think). I used gzippo and express.compress(). Both gzipp the files one time. There is no Content-Encoding:gzip if I refresh the page again.
Her is how I setup my express app:
var gzippo = require('gzippo');
var express = require('express');
var app = express();
app.use(express.compress());
app.use(app.router);
app.use(gzippo.staticGzip(__dirname + '/www'));
This is what Chrome network Response Headers show after page update:
EDITED for full request headers
GET / HTTP/1.1
Host: myhost.com
Connection: keep-alive
Cache-Control: max-age=0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/ *;q=0.8
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.146 Safari/537.36
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Cookie: __utma=161759779.498387976.1381482631.1394444924.1394395346.80; __utmb=161759779.3.10.1394395346; __utmc=161759779; __utmz=161759779.1394444924.79.7.utmcsr=gtmetrix.com|utmccn=(referral)|utmcmd=referral|utmcct=/reports/myhost.com/5iXAs1ej/retest
If-None-Match: "25020-1394452200000"
If-Modified-Since: Mon, 10 Mar 2014 11:50:00 GMT
If I refresh again it shows: Edited with full response headers.
HTTP/1.1 304 Not Modified
x-powered-by: Express
accept-ranges: bytes
etag: "25020-1394452200000"
date: Mon, 10 Mar 2014 10:51:45 GMT
cache-control: public, max-age=0
last-modified: Mon, 10 Mar 2014 11:50:00 GMT
If I edit the page again I get Content-Encoding:gzip but only one time.
I don't know if there is something wrong with my express setup.
NOTE: I serve my page as: res.sendfile(__dirname + '/www/index.html');

Answer 1

If I edit the page again I get Content-Encoding:gzip but only one time. I don't know if there is something wrong with my express setup.
All is well. The first time your server sends the file with gzip compression. The second time the normal etag cacheing mechanism comes into play, and since the file has not been modified, the server tells the browser "you already have the right version of this file" and thus there is no need for the server to send a response body at all, just headers, thus no need for any Content-Encoding header.