I2P proxy configuration via PAC file

2010-12-19 23:16

With the new french Hadopi law… I just tested the I2P nework, which works fairly well.

Installation is very easy. Just download the .exe file. Then launch it with the java -jar command, like explained on the official site (and it works on Linux, yes !).

Now, if you want to access .i2p sites, like http://forum.i2p, you must configure your browser to use the I2P proxy: localhost:4444

If you don’t want to use the proxy when connecting to standard non-i2p sites, you can use the FoxyProxy Firefox extension.

You can also use a PAC (Proxy Auto-Config) file:

function FindProxyForURL(url, host) {
    if (dnsDomainIs(host, ".i2p")) {
        return "PROXY localhost:4444";
    } else {
        return "DIRECT";
    }
}

Then configure Firefox, or proxy configuration in Gnome to use the file:///path/to/proxy.pac file as configuration.

Warning: a bad eepsite (.i2p site), can detect your real IP address with that.

Links:

2010-12-19 23:16 · Tags: , ,

Preload web content using link prefetch or javascript

2010-10-30 16:50

For the Bizou php gallery, I looked for different ways of preloading next image in “view” mode (example).

With Firefox it’s very simple. Just use the following element and the browser will preload your contents.
Contents are preloaded in background, once the whole current page is loaded.

 [html]
<link rel="prefetch" href="/images/nextimage.jpg" />

Problem: only Firefox supports this currently.
Note: a ticket is opened about this in the Chromium project.

For other browsers, use some Javascript triggered by the window.onload event:

 [javascript]
<script type="text/javascript">
window.onload = function() {
    // for images
    var im = new Image();
    im.src = '/images/nextimage.jpg';
    // and for other content
    var req = new XMLHttpRequest();
    req.open('GET', 'nextpage.php', false);
    req.send(null);
};
</script>

Beware of HTTP cache headers sent by the server to the browser.
To preload correctly PHP pages, make your script send an Expires header:

header('Expires: '.gmdate('D, d M Y H:i:s \G\M\T', time() + 3600));

Then, for a simple browser detection from your PHP script:

<?php if (strpos($_SERVER['HTTP_USER_AGENT'], 'Firefox') !== false) { ?>
<link rel="prefetch" href="nextpage.php" />

<?php } else { ?>
<script type="text/javascript">
window.onload = function() {
    var req = new XMLHttpRequest();
    req.open('GET', 'nextpage.php', false);
    req.send(null);
};
</script>
<?php } ?>

Links :

2010-10-30 16:50 · Tags: , , , , ,