dynamic-host.lsl

// --[ Dynamic Host ]-------------------
// This script allows you to register a URL for your object.
// The registration process will attempt to verify that your object
// may be contacted before it responds.

string host = "http://services.lewismoten.com/sl/dynamic-host/";

// Leave these as they are
key urlRequestId = NULL_KEY;
key registerRequestId = NULL_KEY;
string url = "";
integer isRegistered = FALSE;

processRequest(key id, string method, string body)
{
    // The world is talking to me. I better do something about it.
    llHTTPResponse(id, 200, "Hello World! I am an object!");
}

initialize()
{
    string myUrl = host + (string)llGetKey();
    llOwnerSay("My external URL is " + myUrl);

    changeUrl();
}

changeUrl()
{
    llSetTimerEvent(0);
    isRegistered = FALSE;

    if(url != "")
    {
        llReleaseURL(url);
        url = "";
    }

    if(llGetFreeURLs() == 0)
    {
        tryAgainLater();
        return;
    }

    urlRequestId = llRequestURL();
}

register()
{
    isRegistered = FALSE;
    string registrationUrl = host + "register";
    list headers = [HTTP_METHOD, "POST"];
    headers += [HTTP_MIMETYPE, "application/x-www-form-urlencoded"];
    string body = "url=" + llEscapeURL(url);
    registerRequestId = llHTTPRequest(registrationUrl, headers, body);
}

processUrlAssignment(string method, string body)
{
    if(method == URL_REQUEST_GRANTED)
    {
        url = body;
        register();
    }
    else
    {
        tryAgainLater();
    }
}

processPingRequest(key id)
{
    llHTTPResponse(id, 200, "pong");
}

registered()
{
    isRegistered = TRUE;
}

tryAgainLater()
{
    llSetTimerEvent(300);
}

default
{
    state_entry()
    {
        initialize();
    }

    on_rez(integer start_parameter)
    {
        initialize();
    }

    changed(integer change)
    {
        if(change & CHANGED_REGION_START)
        {
            changeUrl();
        }
        else if(change & CHANGED_REGION)
        {
            changeUrl();
        }
        else if(change & CHANGED_OWNER)
        {
            changeUrl();
        }
    }

    http_response(key id, integer status, list metadata, string body)
    {
        if(id == registerRequestId)
        {
            if(status == 200 && body == "registered")
            {
                registered();
            }
            else
            {
                tryAgainLater();
            }
        }
    }

    http_request(key id, string method, string body)
    {
        if(urlRequestId == id)
        {
            processUrlAssignment(method, body);
            return;
        }

        if(llGetHTTPHeader(id, "x-path-info") == "/ping")
        {
            processPingRequest(id);
            return;
        }

        processRequest(id, method, body);
    }

    timer()
    {
        if(url == "")
        {
            changeUrl();
        }
        else
        {
            register();
        }
    }
}