Receiving files form PLUpload in WICKET - ajax

Im trying to integrate PLUpload into my wicket application. First steps are looking clear. Im able to choose files and when i click the "upload"-button i receive an request on server-side in my PLUploadBehavior based on AbstractDefaultAjaxBehavior. But it does not seems to be a MultiPart request.
public abstract class PLUploadBehavior extends AbstractDefaultAjaxBehavior {
public PLUploadBehavior() {
}
#Override
public void renderHead(final Component component, IHeaderResponse response) {
super.renderHead(component, response);
response.render(JavaScriptHeaderItem.forReference(new JavaScriptResourceReference(PLUploadBehavior.class, "plupload.full.min.js"));
StringBuffer script = new StringBuffer();
//build the init-script...
response.render(OnLoadHeaderItem.forScript(script.toString()));
}
#Override
protected void respond(AjaxRequestTarget target) {
Request request = getComponent().getRequest();
//received request here, but don't know hot to access files
if (request instanceof IMultipartWebRequest) {
System.out.println("Multipart!!!");
}
}
}
I followed the tutorial for plupload and have no form in my html template. There is none in the tutorial, so i think i don't need it. Anyone an idea to access the files on server-side?

After some more coffee i found the solution to my problem. The example on wicket in action can get adapted to the use with an Behavior. Thanks to Martin Grigorov and the great Wicket Team!

Related

Catching exception for server not available

I am new in spring boot and programming world .I am trying to post data on another server. I am using rest template to do that. I want to catch an exception when the server is not available .I am not sure how to do that .It would be helpful if anyone can just guide me where to look .I find so many examples but its getting more confusing.
Thanks in advance for your help.
You can use #Error Handler for this.You can use in your controller class to look around how this works when called.
#PostMapping("/hello")
public void hello(String msg)
{
RestTemplate restTemplate= new RestTemplate();
HttpEntity<String>reqEntity= new HttpEntity<>(msg);
restTemplate.postForEntity(" paste your server url here", reqEntity, String.class);
}
#ExceptionHandler(ConnectException.class)
#ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
public void func()
{
System.out.println("I am not able to connect");
}
As you mentioned the server is not running so it will be handled by below mentioned function func on which #Exception handler is declared.You can read on #Exception handler.Certainly there are many different ways to do it.

ajax Spring liferay

I'm using an architetture that has: AJAX, Liferay 6.2, Spring 4.3.18.RELEASE;
From AJAX i make a call to the backend, that pass throu liferay and reach my controller;
Now, I want to generete an exception in the controller in order to reach the the failure of the ajax call; I've googled a lot but I wasn't able to find the solution.
my controller:
#Controller("movemementCon")
#RequestMapping("VIEW")
public class movemementCon {
#ResourceMapping("getDis")
#ResponseBody
public ResponseEntity<BenException> getImp(ResourceRequest request, ResourceResponse response, Model model) throws BenException{
return new ResponseEntity<BenException>(HttpStatus.NOT_ACCEPTABLE);
}
But when i reach the code in javascript (the AJAX call) it ignored definitively that I've throw an exception;
The desidered behaviur is that i force to go to the error statment in the AJAX call.
In web browser you can't catch java errors on client side, because client doesn't know anything about backend. You have to catch that error in spring controller method and then return ResponseEntity with some status, response body, custom response headers, so you can notify client that something went wrong and handle it correctly there.
#Controller("movemementCon")
#RequestMapping("VIEW")
public class movemementCon {
#ResourceMapping("getDis")
#ResponseBody
public ResponseEntity<SomeClass> getImp(ResourceRequest request, ResourceResponse response, Model model) {
try{
deleteFromDatabase(model);
} catch(BenException e) {
return new ResponseEntity<>(HttpStatus.NOT_ACCEPTABLE);
}
return new ResponseEntity<>(HttpStatus.OK);
}
}
Then in your JS read the status and execute right action.

ASP.NET Web API session or something?

I need to store some information in session(or in whatever in ASP.NET Web API) that I need to retrieve in every API request. We will have one api IIS web site and multiple web site binding will be added through host header. When any request comes in for example, api.xyz.com, host header will be checked and store that website information in session that will be used in each subsequent api request when making a call to database.
I know there is no support for session in ASP.NET Web API. Is there any other way to handle this kind of situation? Where can I store information that can be retrieving in each subsequent request?
thanks.
in Global.asax add
public override void Init()
{
this.PostAuthenticateRequest += MvcApplication_PostAuthenticateRequest;
base.Init();
}
void MvcApplication_PostAuthenticateRequest(object sender, EventArgs e)
{
System.Web.HttpContext.Current.SetSessionStateBehavior(
SessionStateBehavior.Required);
}
give it a shot ;)
Well, REST by design is stateless. By adding session (or anything else of that kind) you are making it stateful and defeating any purpose of having a RESTful API.
The whole idea of RESTful service is that every resource is uniquely addressable using a universal syntax for use in hypermedia links and each HTTP request should carry enough information by itself for its recipient to process it to be in complete harmony with the stateless nature of HTTP".
So whatever you are trying to do with Web API here, should most likely be re-architectured if you wish to have a RESTful API.
With that said, if you are still willing to go down that route, there is a hacky way of adding session to Web API, and it's been posted by Imran here http://forums.asp.net/t/1780385.aspx/1
Code (though I wouldn't really recommend that):
public class MyHttpControllerHandler
: HttpControllerHandler, IRequiresSessionState
{
public MyHttpControllerHandler(RouteData routeData): base(routeData)
{ }
}
public class MyHttpControllerRouteHandler : HttpControllerRouteHandler
{
protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
{
return new MyHttpControllerHandler(requestContext.RouteData);
}
}
public class ValuesController : ApiController
{
public string GET(string input)
{
var session = HttpContext.Current.Session;
if (session != null)
{
if (session["Time"] == null)
{
session["Time"] = DateTime.Now;
}
return "Session Time: " + session["Time"] + input;
}
return "Session is not availabe" + input;
}
}
and then add the HttpControllerHandler to your API route:
route.RouteHandler = new MyHttpControllerRouteHandler();
In WebApi 2 you can add this to global.asax
protected void Application_PostAuthorizeRequest()
{
System.Web.HttpContext.Current.SetSessionStateBehavior(System.Web.SessionState.SessionStateBehavior.Required);
}
Then you could access the session through:
HttpContext.Current.Session
You can use cookies if the data is small enough and does not present a security concern. The same HttpContext.Current based approach should work.
Request and response HTTP headers can also be used to pass information between service calls.
Now in 2017 with ASP.Net Core you can do it as explained here.
The Microsoft.AspNetCore.Session package provides middleware for managing session state.
Startup.cs
public void ConfigureServices(IServiceCollection services)
{
// Adds a default in-memory implementation of IDistributedCache.
services.AddDistributedMemoryCache();
services.AddSession(options =>
{
// Set a short timeout for easy testing.
options.IdleTimeout = TimeSpan.FromSeconds(10);
options.Cookie.HttpOnly = true;
});
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
app.UseSession();
}
From the Docs:
Introduction to session and application state in ASP.NET Core
Already tested on a working project

Is it possible to get around the Cross-Origin limitation when calling the Google Places API Web service?

Is it possible enable the Google Placess API WebService to allow cross-origin requests from my domain so that I can access the service directly from the browser? I'v been experimenting with the API-keys by creating a Browser API key and then adding my domain to the referers list, but to no avail. Not sure if that is what the refeferer property is for anyway.
Is this limitation by design, or am I missing something here?
Google Places API WebService is the service that I want to use. Neither the Places Autocomplete or Places Search in the Places Library are suitable for my particular requirement.
Cheers
Stian
This is a client-side based limitation, so the short answer is: no.
However there are websites and services that try to surmount this problem by using scripts (loading them on the fly).
Have a look here and here (these articles are about generic cross-domain AJAX requests)
The Places-API is also available inside the Maps-Javascript-API, you don't need to struggle with cross-origins there.
Let me say its impossible to get around .I tried using java instead the code just works for http request(i used here is for graph.facebook.com):
public class search {
private static String readAll(Reader rd) throws IOException {
StringBuilder sb = new StringBuilder();
int cp;
while ((cp = rd.read()) != -1) {
sb.append((char) cp);
}
return sb.toString();
}
public static JSONObject readJsonFromUrl(String url) throws IOException, JSONException {
InputStream is = new URL(url).openStream();
try {
BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8")));
String jsonText = readAll(rd);
JSONObject json = new JSONObject(jsonText);
return json;
} finally {
is.close();
}
}
public static void main(String[] args) throws Exception{
// TODO Auto-generated method stub
System.getProperties().put("http.proxyHost", "172.16.0.2");
System.getProperties().put("http.proxyPort", "8080");
JSONObject json = readJsonFromUrl("http://maps.googleapis.com/maps/api/place/nearbysearch/json?key=AIzaSyBRlMLIdoTk-j4OZCucR47rVMLhMmvZVRw&type=hospital&location=12.8213125%2C80.0442&radius=500&_=1427359809583");
System.out.println(json.toString());
// System.out.println(json.get("about"));
// System.out.println("hello ");
}
}
If you replace the link with places api web search it will not work,the reason is that google does not give its services on HTTP domain,,, and my code only works on HTTP domain(not HTTPS)

Spring 3.0 RESTful Controller Fails on Redirect

I am setting up a simple RESTful controller for a Todo resource with an XML representation. It all works great - until I try to redirect. For example, when I POST a new Todo and attempt to redirect to its new URL (for example /todos/5, I get the following error:
Error 500 Unable to locate object to be marshalled in model: {}
I do know the POST worked because I can manually go to the new URL (/todos/5) and see the newly created resource. Its only when trying to redirect that I get the failure. I know in my example I could just return the newly created Todo object, but I have other cases where a redirect makes sense. The error looks like a marshaling problem, but like I said, it only rears itself when I add redirects to my RESTful methods, and does not occur if manually hitting the URL I am redirecting to.
A snippet of the code:
#Controller
#RequestMapping("/todos")
public class TodoController {
#RequestMapping(value="/{id}", method=GET)
public Todo getTodo(#PathVariable long id) {
return todoRepository.findById(id);
}
#RequestMapping(method=POST)
public String newTodo(#RequestBody Todo todo) {
todoRepository.save(todo); // generates and sets the ID on the todo object
return "redirect:/todos/" + todo.getId();
}
... more methods ...
public void setTodoRepository(TodoRepository todoRepository) {
this.todoRepository = todoRepository;
}
private TodoRepository todoRepository;
}
Can you spot what I am missing? I am suspecting it may have something to do with returning a redirect string - perhaps instead of it triggering a redirect it is actually being passed to the XML marshaling view used by my view resolver (not shown - but typical of all the online examples), and JAXB (the configured OXM tool) doesn't know what to do with it. Just a guess...
Thanks in advance.
This happend because redirect: prefix is handled by InternalResourceViewResolver (actually, by UrlBasedViewResolver). So, if you don't have InternalResourceViewResolver or your request doesn't get into it during view resolution process, redirect is not handled.
To solve it, you can either return a RedirectView from your controller method, or add a custom view resolver for handling redirects:
public class RedirectViewResolver implements ViewResolver, Ordered {
private int order = Integer.MIN_VALUE;
public View resolveViewName(String viewName, Locale arg1) throws Exception {
if (viewName.startsWith(UrlBasedViewResolver.REDIRECT_URL_PREFIX)) {
String redirectUrl = viewName.substring(UrlBasedViewResolver.REDIRECT_URL_PREFIX.length());
return new RedirectView(redirectUrl, true);
}
return null;
}
public int getOrder() {
return order;
}
public void setOrder(int order) {
this.order = order;
}
}

Resources