Engine.debugName("http_ping");
Message.trackName("http_ping");

url = "http://10.10.10.10/ping=";
send = true;

function onHTTPQual(msg)
{
    if (url.startsWith(msg.server))
	send = !!msg.available;
    var str = "activated";
    if (!send)
	str = "deactivated";
    Engine.debug(Engine.DebugInfo,"Sending ping is " + str);
    return false; // let others see the message too
}

function onInterval()
{
    if (send) {
	Engine.debug(Engine.DebugAll,"Sending ping");
	var m = new Message("http.request");
	m.module = "http_ping";
	m.url = url + Date.now();
	m.wait = false;
	m.timeout = 5000;
	m.enqueue();
    }
    else
	Engine.debug(Engine.DebugNote,"Cannot set ping, server is down");
}

Message.install(onHTTPQual,"http.qualify",50);
Engine.setInterval(onInterval,5000);