Wicket fileUploadField.getFileUpload returning null on AjaxBehaviour - wicket

I am trying to get FileUpload from fileupload field on 'onChange' event in wicket.
But it is always giving null after selecting a file. My code looks like this,
fileUploadField.add(new AjaxEventBehavior("onChange") {
#Override
protected void onEvent(AjaxRequestTarget target) {
FileUpload fileUpload = fileUploadField.getFileUpload();
if(fileUpload!=null) {
//my code
}
}
}
I also tried with AjaxFormComponentUpdatingBehavior("onChange").
Please help me.

The FileUpload is really null using AJAX call, because file upload is processing in following steps.
Choose file in a form field
Post the form using HTTP POST request
Receive the HTTP POST request on the server side
Parse the request to a the FileUpload
If you just add an onChange ajax event on your file input field it causes just a GET request on an URL, but it doesn't send the form data.
You can try OnChangeAjaxBehavior or AjaxButton as shown in examples on http://www.wicket-library.com/wicket-examples/ajax/upload

Related

How to produce rendered output from a Sling POST in AEM?

It seems like Sling expects every form POST to modify the JCR. So the expected/standard behavior would be a POST-redirect-GET, which is fine for most things. However, I need to be able to POST to AEM and then use the data in that POST to create a rendered result. Our use of AEM is stateless and so I don't want to carry the POST'd data in Session in order to utilize it in a subsequent GET.
Some have recommended putting the POST'd data in Browser sessionStorage, but that doesn't have broad enough support to be sufficient.
As far as I can tell there is no way for Sling in AEM to take a POST and produce a rendered result.
Here is a screenshot of what a POST produces in the page/resourceType component and in any Sling included jsp's that happen to be involved in the rendering.
I have tried things like using the "nop" operation.
<input type="hidden" name=":operation" value="nop" />
But either way all servlets think a POST is happening and don't render properly.
There is the option of creating a custom servlet, to handle the POST, but then how do you render the templated output and change the request so that all the components think they are serving a GET?
UPDATED:
Here is a screenshot of the "nop" POST.jsp result.
What you can do is create a POST.jsp file in the appropiate resourceType.
If your POST request go to /content/yourapp/something, which has a resourceType: your/app/example. Then you can create a file /apps/your/app/example/POST.jsp with whatever render you wish. You can even include your default rendering script in the POST.jsp file if you need it to be rendered the same as the GET requests.
The other option is to use a servlet registered for POST requests and internally use the SlingRequestProcessor service. That service allow you to programmatically process a request through Sling. You can use a SlingRequestWrapper to wrap your request and override getMethod() to return "GET". That should process the request as if it was a GET request.
This sounds like a somewhat funky use case, IIUC you are using a large request parameter P to drive the rendering?
Using a custom POST servlet should work, if you use something like
slingRequest.getRequestDispatcher(resource).forward(request, response) where request is a wrapper around the actual request, where request.getMethod() returns GET. You can then store your P data in request attributes.
The SlingHttpServletRequestWrapper class can be used to create such wrappers.
Creating a custom servlet to handle a post could be an idea. After successfull write you could redirect to the modified resource - simple 302.
The other solution that comes to my mind is a custom Filter that would do the same. However, since AEM expects to get 200 instead of 302, it would be good to tell by atrribute or parameter that this POST needs to be redirected. Otherwise some of the AEM UI functionalities could brake. This is a quick example of an idea. You would probably need to write something more sophisticated.
#Component(immediate = true)
#Service
#Properties({
#Property(name = Constants.SERVICE_DESCRIPTION, value = "Desc"),
#Property(name = Constants.SERVICE_VENDOR, value = "Company name"),
#Property(name = Constants.SERVICE_RANKING, intValue = RedirectFilter.RANKING),
#Property(name = "filter.scope", value = "request") })
public class RedirectFilter implements Filter {
public static final int RANKING = -1000; // low ranking
#Override
public void init(final FilterConfig filterConfig) throws ServletException {
}
#Override
public void destroy() {
}
#Override
public void doFilter(final ServletRequest request, final ServletResponse response, final FilterChain chain)
throws IOException, ServletException {
if (request.getParameter("redirect").equals("true")) {
((SlingHttpServletResponse) response).sendRedirect(((SlingHttpServletRequest)request).getRequestURI());
}
}
}

Play form binding difficulties - How do I modify a request after getting it in the backend?

I'm currently trying to connect an Extjs form to a Play! Scala backend.
I have no problem receiving the request, but
FormName.bindFromRequest.get returns to me None .
I'm able to find the data generated via submitting from Extjs in the POST request in request.request.body.data (the first request object is generated by SocialSecure's controller), whereas normally the data bound to the form would be found in request.request.body.data.elems
I think Extjs's eschewal of using <form> in their inserted HTML is what causes me this problem, but I'd still like to take advantage of Extjs's nice form verification UI.
Does Play! or Scala have any resources for modifying a request after the server has received it?
More info
This is the method my /requestAudit cuurently points to after a POST request:
def requestAudit = SecuredAction(WithProvider("google")) { // SecureSocial syntax
implicit request => { // let's call this line 0'
println(request.request.body.asFormUrlEncoded) // let's call this line 1'
println(request.body.asText) // let's call this line 2'
newAuditForm.bindFromRequest.fold(
errors => BadRequest(views.html.error(newAuditForm))
success => { /*insert the object into my db*/ }
) } }
Ext.js request
When I'm debugging in Eclipse with an Ext.js form, the Variables window shows: (click for closeup)
where the form values are located in request.body.data.key1, request.body.data.key2, etc
Bootstrap form request
On the other hand, the request for Bootstrap has the values stored in request.body.data.elems
#2manyprojects 's suggestion set me on the right path:
newAuditForm.bindFromRequest(
(request.request.body.asFormUrlEncoded).getOrElse(Map()))
.fold( ... )
worked.
I was still getting form binding errors after changing my code to this, and then I discovered a typo in the name property of one of my Ext.js form fields. The name of the field must be the same on both the UI and the Play Form.

GWT JSONPRequestBuilder - "Unknown Token :" error in browser console with Timeout exception at the end

I am trying to call a Restful WS from GWT using JSOPRequestBuilder. I have a similar issue which was reported in the link
http://groups.google.com/group/google-web-toolkit/browse_thread/thread/ef93383aca7a3dfc/d4dc5bad1a9110ea
But, I could not figure out the solution. Kindly help me at the earliest.
My JAX-WS resource code snippet from server
#GET
#Produces(MediaType.APPLICATION_JSON)
public DealerAddress getDealerAddress(#QueryParam("dealerId") String sDealerId) {
DealerAddress dlrAd = new DealerAddress("test", "test", "test", "test", 10, new Date(), new Date());
return dlrAd;
}
Jersey returns a JSON object of DealerAddress.
Now rest URL "https://127.0.0.1:8181/application/rest/OrderManagementResource?alt=json-in-script&dealerId=DLR1"
works absolutely fine when i tried request in browser.
It even works with RequestBuilder approach from GWT but not with JSONPRequestBuilder approach.
Code snippet to invoke WS from GWT using JSONPRequestBuilder
JsonpRequestBuilder jsonPReqBuilder = new JsonpRequestBuilder();
jsonPReqBuilder.setTimeout(100000);
jsonPReqBuilder.setCallbackParam("callback");
jsonPReqBuilder.requestObject("https://127.0.0.1:8181/application/rest/OrderManagementResource?alt=json-in-script&dealerId=DLR1" , new AsyncCallback<DealerAddressJSON>() {
#Override
public void onFailure(Throwable caught) {
// TODO Auto-generated method stub
caught.printStackTrace();
Window.alert("Inside error"+caught.getLocalizedMessage());
}
#Override
public void onSuccess(DealerAddressJSON result) {
// TODO Auto-generated method stub
Window.alert("Inside success"+result);
}
});
where as DealerAddressJSON is a JavaScriptObject type class.
I could see that my JAX Rest resource getting called and saying returning from server.
Also, I could see that in Firebug that the response comes in browser but fails with an exception "Unknown token :"
At the end I always get a Timeout exception.
Now I am in big question whether the way we return JSON from JAX-RS resource is a problem in server
or
JSONPRequestBuilder calling procedure is a problem? I could not understand the callback changes which some of the links explained on this issue.
Kindly help me.
You are probably sending back JSON, while the JSONPRequestBuilder expects JSONP. These are not the same thing.
JSON is just the data, as is - make the request using AJAX (i.e. the RequestBuilder), and the contents can be read directly. These requests can only be made to the same server. Example JSON data:
{"response":"success", "items":[{"id":1}, {"id":2}]}
In contrast, JSONP is designed for cross-origin requests, so instead of just containing the data, the data is wrapped up in a JavaScript. Since your JSON service isn't wrapping the a response in a js function call, this isn't working. Example JSONP data:
callback_1({"response":"success", "items":[{"id":1}, {"id":2}]})
The callback changes with each request, so the server is supposed to change that callback function based on what the client requested each time.

How to retrieve inputStream from the server using fileUploader and GWT 2.4?

I have a fileUploader widget that I'm using to select an xml file. I then have a button that calls my handler in the viewImpl class when the user submits the selected file. If I understand things correctly, from there I do a submit from the formPanel and the file is on the server.
#UiHandler("calculateComplexityButton")
void onClickCalculateComplexity(ClickEvent e){
formPanel.submit();
//How do I get the inputStream back to here????
presenter.getTask(inputStream);
}
My problem is how do I get the inputStream off the server? I tried using an RPC call for all this, but when I try to get the inputStream I'm not pulling anything off the server. I tried:
inputStream = request.getInputStream();
but it appears to be empty. Any ideas on this?
I dropped the RPC code and used a simple HTTPRequest I found here. That gets me to the servlet, but the request doesn't have the file stream. When I reach this line in the code:
FileItemIterator iter = upload.getItemIterator(request); //Nothing is here in iter.
You can not make an upload via RPC, thats why you have to submit your form to a servlet.
final FormPanel form = new FormPanel();
form.setEncoding(FormPanel.ENCODING_MULTIPART);
form.setMethod(FormPanel.METHOD_POST);
form.setAction("/upload");
So, when you do form.submit() it will send your file to the Action(Servlet). In the server side you can use the lib form apache (commons-fileupload). You have many different way to get your file, you can save on disk, read on memory....

GWT request to download file

I know it's not possible to send an ajax request or use GWT's RequestBuidler to send a request for a file download; needing a form to do it but how do I get a reference to the response when it returns with lets say an error.
The request i send is for a file download but if the file download is too big the Java servlet responds with an error, how do i get a reference to this error to handle it appropriately on the GWT side.
You can add a FormPanel.SubmitCompleteHandler to the form and parse the results in onSubmitComplete().
With extGWT you can parse the HTML response to know the HTML error code
For instance
com.extjs.gxt.ui.client.widget.Component.addListener(Events.Submit, new Listener<FormEvent>()
{
public void handleEvent(final FormEvent event)
{
String htmlResponse = event.getResultHtml();
(...)
}
});