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Tapestry5 : URL Re-writing : Pass parameters to transformPageRenderLink method

I am upgrading tapestry from 5.2.4 to 5.3.8 and am stuck at re-implementing the URL re-writing part.
In my application a user account can have multiple data stores. User can have same page of different stores active at the same time. Hence I need to put the storeId in page links and event links URLs. So What is done is as follows.
I register MyLinkTransformerClass in AppModule as follows.
#Contribute(PageRenderLinkTransformer.class)
#Primary
public static void provideURLRewriting( OrderedConfiguration<PageRenderLinkTransformer> configuration){
configuration.addInstance(
"Faces", MyLinkTransformer.class);
}
Following is the MyLinkTransformer class which implements PageRenderLinkTransformer
public PageRenderRequestParameters decodePageRenderRequest(
Request request) {
// for incoming requests - remove the store id from URL and
// save into Request as an attribute
String path = request.getPath();
if (path.equals("/")) {
// Redirect to accounts page
return new PageRenderRequestParameters("account", new EmptyEventContext(), false);
}
else {
String start = path.split("/")[1];
if (!ignoredRewriteSet.contains(start) && !start.startsWith("account")) {
String storePath = path.substring(1).substring(path.indexOf("/"));
int idx = storePath.indexOf("/");
if (idx < 0) idx = storePath.length();
String storeId = storePath.substring(0, idx).trim();
RequestHelper.setStoreId(request, storeId);
EventContext urlEventContext = new URLEventContext(contextValueEncoder, new String[]{storeId});
EventContext arrayEventContext = new ArrayEventContext(typeCoercer, "foo");
return new PageRenderRequestParameters(storePath.substring(idx), arrayEventContext, false);
//return new PageRenderRequestParameters(storePath.substring(idx), new EmptyEventContext(), false);
}
}
return null;
}
public Link transformPageRenderLink(
Link defaultLink,
PageRenderRequestParameters parameters) {
// for outgoing requests- This is where I want to access the store Id
// which is stored in Request class of Tapestry as an attribute and
// add it to the URL
return null;
}
So, the idea is to remove storeId from URL in decodePageRenderRequest method and save it in the Request class of Tapestry as an attribute. And while creating outgoing URLs of page link and event link, I want to access the storeId which was saved in Request and inject it to the URL which will be rendered in method transformPageRenderLink.
But I don't know how to pass parameters to transformPageRenderLink method or access Request instance there.
I am following http://blog.tapestry5.de/index.php/2010/09/06/new-url-rewriting-api/ example.
I am new to URL Rewriting, any help with this will be appreciated.

You will probably be interested in the ModeComponentEventLinkEncoder here. It removes a "mode" from the URL and puts it onto the Environment before passing it on to the normal tapestry URL processing.
It's a two way process so the "mode" is included in any links generated on the page.
Note: This is applied as a decorator here

Call JSP method from javascript

I have the above js and JSP code, I want to invoke procedureCall() while clicking on ok button on confirm window poopup (inside "if" statement). Is it possible and if yes, how it can be done?
<script type="text/javascript">
function confirmDelete() {
var answer = confirm("Are you sure you want to delete");
if (answer == true) {
return true;
} else {
return false;
}
}
</script>
JSP piece:
<%! public void procedureCall(int cId) {
String procedureCall = "{call NEW_PORTING_PRC.delete_album_metadata(cId)}";
try (CallableStatement cal = conn.prepareCall(procedureCall);) {
} catch (Exception e) {
e.printStackTrace();
}
%>

javascript runs in your browser, your java code is deployed in your container(Tomcat).
So only way to invoke this is via a Web call. Your javascript should invoke an ajax call to one servlet(configured in web.xml) and this servlet should invoke your java method.
like from JS you write as
$.get('URLofServlet');
OR
what you can try is submit the JSp with some parameters and reloading the JSP..
if (answer == true)
{
document.getElementById("param1").value='paramvalue';
document.getElementById("myForm").action='yourJspPath.jsp';
document.getElementById("myForm").submit();
}
Also I assume id and name will both be 'param1' for simplicity..
and in scriptlet you can do like
<%
if(request.getParamter("param1")=='paramvalue'){procedureCall();}
%>
Just to add I will recommend to remove scriplets and use ajax as in first approach.

Use form submission or ajax request or framework action to go back end and process the things needed for you.In your approach its not possible I think.
And please dont use scriplets in jsp,its not a good practice.

Firefox, websockets and odd behaviours

Background:
Using WebSockets with JavaScript + Play! framework (2.2).
Can send and receive data fine in Chrome.
Can only receive data (from server) in Firefox as send() doesn't trigger any callbacks.
In addition to the send issue, and in Firefox only again, the tab for the page is always stuck on "connecting" while the spinner keeps spinning (see figure 1).
Misbehaving Browser:
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:24.0)(Firefox 24.0)
(Figure 1. Firefox tab after page has loaded and data is shown)
Any time I refresh the web page, I receive the error below, attributed to the constant page loading behaviour I'm sure.
The connection to ws://localhost:9000/ was interrupted while the page was loading.
The entire JavaScript code:
$(function() {
var chatSocket = new WebSocket("#routes.Application.getMetaData().webSocketURL(request)");
var sendMessage = function() {
chatSocket.send(JSON.stringify({
id: "unique",
name: "a name",
age: 22
}));
}
var receiveEvent = function(event) {
var data = JSON.parse(event.data)
document.write(data.age);
document.write(data.name);
document.write(data.message);
document.write("\n");
sendMessage();
chatSocket.close();
}
chatSocket.onmessage = receiveEvent
})
Now In the past, I've been trying with MozWebSocket instead of the standard WebSocket, but I get nothing rendered on screen using that module therefore unless there is an angle I've missed, WebSocket is the better one to use.
The relevant Play! block:
public static WebSocket<JsonNode> getMetaData() {
return new WebSocket<JsonNode>() {
// Called when the Websocket Handshake is done.
public void onReady(WebSocket.In<JsonNode> in, WebSocket.Out<JsonNode> out) {
// For each event received on the socket,
in.onMessage(new Callback<JsonNode>() {
#Override
public void invoke(JsonNode jsonNode) {
System.out.println("Message Incoming!");
System.out.println(jsonNode.get("id"));
System.out.println(jsonNode.get("name"));
System.out.println(jsonNode.get("age"));
}
});
// When the socket is closed.
in.onClose(new Callback0() {
public void invoke() {
System.out.println("Disconnected");
}
});
ObjectNode node = Json.newObject();
node.put("message", "hello");
node.put("name", "client");
node.put("age", 1);
out.write(node);
//same result commented/uncommented
out.close();
}
};
}
So in Chrome, the flow would be:
document.write(...)
"Message Incoming!"
... JSON attributes
"Disconnected"
But in Firefox, the flow is:
document.write(...)
"Disconnected"
Any help in diagnosing these problems would be greatly appreciated. I have no intention of supporting IE, but having both Mozilla and Chrome working would be great.
Other JavaScript Warnings:
Below is a warning I occasionally get in Firefox's console while pointing at the "ws" protocol as the culprit. What its relevance is to my problem, I do not know.
Use of getPreventDefault() is deprecated. Use defaultPrevented instead.

You call document.write() after the document is loaded, which then implies document.open() which in turn replaces the document and by that unloads the old one and aborts stuff like timeouts or websockets.
Use something other than document.write() and you should be fine.

Render page to string in Wicket 1.5

I'm working on upgrading our existing Wicket webapp to 1.5 and have hit a snag in our renderPage function that we use to render our HTML emails.
Previously we used the code referenced/listed in this StackOverflow question and this (currently broken but maybe fixed later) link but that code no longer works as a lot of those classes don't exist in 1.5.
I also found this email thread but it is light on the details and I don't know how to create the WebPage from my pageClass and parameters.
http://apache-wicket.1842946.n4.nabble.com/Render-WebPage-to-String-in-Wicket-1-5-td3622130.html
Here is my code:
// Renders a page under a temporary request cycle in order to get the rendered markup
public static String renderPage(Class<? extends Page> pageClass, PageParameters pageParameters)
{
//get the servlet context
WebApplication application = (WebApplication) WebApplication.get();
ServletContext context = application.getServletContext();
//fake a request/response cycle
MockHttpSession servletSession = new MockHttpSession(context);
servletSession.setTemporary(true);
MockHttpServletRequest servletRequest = new MockHttpServletRequest(application, servletSession, context);
MockHttpServletResponse servletResponse = new MockHttpServletResponse(servletRequest);
//initialize request and response
servletRequest.initialize();
servletResponse.initialize();
WebRequest webRequest = new ServletWebRequest(servletRequest);
BufferedWebResponse webResponse = new BufferedWebResponse(servletResponse);
webResponse.setAjax(true);
WebRequestCycle requestCycle = new WebRequestCycle(application, webRequest, webResponse);
requestCycle.setRequestTarget(new BookmarkablePageRequestTarget(pageClass, pageParameters));
try
{
requestCycle.getProcessor().respond(requestCycle);
if (requestCycle.wasHandled() == false)
{
requestCycle.setRequestTarget(new WebErrorCodeResponseTarget(HttpServletResponse.SC_NOT_FOUND));
}
}
finally
{
requestCycle.detach();
requestCycle.getResponse().close();
}
return webResponse.toString();
}
Specifically, the code breaks because the WebRequestCycle and BookmarkablePageRequestTarget classes no longer exist. I feel like I should be able to use the StringResponse class some how but I'm missing the link that would help me trigger a render on that response.
Any help would be appreciated. Thanks.
My Final Solution
Using the example that I was directed to by the answer below I ended up with the following code. I'm pasting it here as well so that if that link disappears or is changed with a future version of Wicket then people from the future will still be able to get the answer they need.
I ended up passing in a PageProvider because in some cases I needed to pass in an instantiated Page and in others a pageClass + parameters.
public static String renderPage(final PageProvider pageProvider)
{
final RenderPageRequestHandler handler = new RenderPageRequestHandler(pageProvider, RedirectPolicy.NEVER_REDIRECT);
final PageRenderer pageRenderer = Application.get().getPageRendererProvider().get(handler);
RequestCycle requestCycle = RequestCycle.get();
final Response oldResponse = requestCycle.getResponse();
BufferedWebResponse tempResponse = new BufferedWebResponse(null);
try
{
requestCycle.setResponse(tempResponse);
pageRenderer.respond(requestCycle);
}
finally
{
requestCycle.setResponse(oldResponse);
}
return tempResponse.getText().toString();
}

Check the source code of http://www.wicket-library.com/wicket-examples/mailtemplate/ example.

HTMLUnit doesn't wait for Javascript

I have a GWT based page that I would like to create an HTML snapshot for it using HtmlUnit.
The page loads using Ajax/JavaScript information on a product, so for about 1 second there is a Loading... message and then the content appears.
The problem is that HtmlUnit doesn't seem to capture the information and all I'm getting is the "Loading..." span.
Below is an experimental code with HtmlUnit where I try to give it enough time to wait for the loading of the data but it doesn't seem to change anything and I am still unable to capture the data loaded by the GWT javascript.
WebClient webClient = new WebClient();
webClient.setJavaScriptEnabled(true);
webClient.setThrowExceptionOnScriptError(false);
webClient.setAjaxController(new NicelyResynchronizingAjaxController());
WebRequest request = new WebRequest(new URL("<my_url>"));
HtmlPage page = webClient.getPage(request);
int i = webClient.waitForBackgroundJavaScript(1000);
while (i > 0)
{
i = webClient.waitForBackgroundJavaScript(1000);
if (i == 0)
{
break;
}
synchronized (page)
{
System.out.println("wait");
page.wait(500);
}
}
webClient.getAjaxController().processSynchron(page, request, false);
System.out.println(page.asXml());
Any ideas...?

Thank you for responding.
I actually should have reported this sooner that I have found the solution myself.
Apparently when initialising WebClient with FF:
WebClient webClient = new WebClient(BrowserVersion.FIREFOX_3_6);
It seem to be working.
When initialising WebClient with the default constructor it uses IE7 by default and I guess FF has better support for Ajax and is the recommended emulator to use.

I believe by default NicelyResynchronizingAjaxController will only resynchronize AJAX calls that were caused by a user action, by tracking which thread it originated from. Perhaps the GWT generated JavaScript is being called by some other thread which NicelyResynchronizingAjaxController does not want to wait for.
Try declaring your own AjaxController to synchronize with everything regardless of originating thread:
webClient.setAjaxController(new AjaxController(){
#Override
public boolean processSynchron(HtmlPage page, WebRequest request, boolean async)
{
return true;
}
});

As documentation states, waitForBackgroundJavaScript is experimental:
Experimental API: May be changed in next release and may not yet work perfectly!
The next approach has always worked for me, regardless of the BrowserVersion used:
int tries = 5; // Amount of tries to avoid infinite loop
while (tries > 0 && aCondition) {
tries--;
synchronized(page) {
page.wait(2000); // How often to check
}
}
Note aCondition is whatever you're checking for. EG:
page.getElementById("loading-text-element").asText().equals("Loading...")

None of the so far provided solutions worked for me. I ended up with Dan Alvizu's solution + my own hack:
private WebClient webClient = new WebClient();
public void scrapPage() {
makeWebClientWaitThroughJavaScriptLoadings();
HtmlPage page = login();
//do something that causes JavaScript loading
waitOutLoading(page);
}
private void makeWebClientWaitThroughJavaScriptLoadings() {
webClient.setAjaxController(new AjaxController(){
#Override
public boolean processSynchron(HtmlPage page, WebRequest request, boolean async)
{
return true;
}
});
}
private void waitOutLoading(HtmlPage page) {
while(page.asText().contains("Please wait while loading!")){
webClient.waitForBackgroundJavaScript(100);
}
}
Needless to say, "Please wait while loading!" should be replaced with whatever text is shown while your page is loading. If there is no text, maybe there is a way to check for existence of some gif (if that is used). Of course, you could simply provide a big enough milliseconds value if you're feeling adventurous.