gecko-dev/netwerk/test/unit/test_bug561276.js

//
// Verify that we hit the net if we discover a cycle of redirects
// coming from cache.
//

const {HttpServer} = ChromeUtils.import("resource://testing-common/httpd.js");

var httpserver = new HttpServer();
var iteration = 0;

function setupChannel(suffix)
{
    var chan = NetUtil.newChannel({
      uri: "http://localhost:" + httpserver.identity.primaryPort + suffix,
      loadUsingSystemPrincipal: true
    });
    var httpChan = chan.QueryInterface(Ci.nsIHttpChannel);
    httpChan.requestMethod = "GET";
    return httpChan;
}

function checkValueAndTrigger(request, data, ctx)
{
    Assert.equal("Ok", data);
    httpserver.stop(do_test_finished);
}

function run_test()
{
    httpserver.registerPathHandler("/redirect1", redirectHandler1);
    httpserver.registerPathHandler("/redirect2", redirectHandler2);
    httpserver.start(-1);

    // clear cache
    evict_cache_entries();

    // load first time
    var channel = setupChannel("/redirect1");
    channel.asyncOpen(new ChannelListener(checkValueAndTrigger, null));

    do_test_pending();
}

function redirectHandler1(metadata, response)
{
    // first time we return a cacheable 302 pointing to next redirect
	if (iteration < 1) {
	    response.setStatusLine(metadata.httpVersion, 302, "Found");
	    response.setHeader("Cache-Control", "max-age=600", false);
	    response.setHeader("Location", "/redirect2", false);

	// next time called we return 200
    } else {
	    response.setStatusLine(metadata.httpVersion, 200, "Ok");
	    response.setHeader("Cache-Control", "max-age=600", false);
        response.setHeader("Content-Type", "text/plain");
        response.bodyOutputStream.write("Ok", "Ok".length);
    }
	iteration += 1;
}

function redirectHandler2(metadata, response)
{
    response.setStatusLine(metadata.httpVersion, 302, "Found");
    response.setHeader("Cache-Control", "max-age=600", false);
    response.setHeader("Location", "/redirect1", false);
}