When I try to upload file in Wicket I've got the following exception:
"ERROR org.apache.wicket.RequestCycle.logRuntimeException(RequestCycle.java:1529) - ServletRequest does not contain multipart content. One possible solution is to explicitly call Form.setMultipart(true), Wicket tries its best to auto-detect multipart forms but there are certain situation where it cannot.
java.lang.IllegalStateException: ServletRequest does not contain multipart content. One possible solution is to explicitly call Form.setMultipart(true), Wicket tries its best to auto-detect multipart forms but there are certain situation where it cannot.
at org.apache.wicket.protocol.http.servlet.MultipartServletWebRequest.<init>(MultipartServletWebRequest.java:113)..."
However, when I set form.MultiPart(true) I can't get Javascript dialog by using:
target.appendJavascript("Some Message");
Does somebody know how to use Javascript when Form.Multipart(true)?
Thanks!
If you want to call the alert dialog as a response for an ajax request, you can use the appendJavascript() method (the argument is javascript code, not a simple string, like the code you posted):
target.appendJavaScript("alert('Some message');");
If you want to call the alert when the page loads, you could use a behavior:
add(new AbstractBehavior() { // or Behavior, on Wicket 1.5
#Override
public void renderHead(Component component, IHeaderResponse response) {
response.renderOnLoadJavaScript("alert('Some message');");
}
});
It's also possible use a Label, and render directly to a <script> tag. Just remember to call setEscapeModelStrings(false):
add(new Label("alert", "alert('Some message');").setEscapeModelStrings(false));
and
<script type="text/javascript" wicket:id="alert"></script>
Related
I have the following POST handler in Spring boot:
#PostMapping("/handlePostRequest")
public ModelAndView handlePostRequest(HttpServletRequest request, #RequestBody ApiRequest apiRequest) {
// ... Do some stuff with POST params ...
ModelAndView mav = new ModelAndView("myview);
mav.addObject("myProperty", myProperty);
return mav;
}
However, when it displays my very simple view, the Javascript onload function is never triggered.
<!DOCTYPE html>
<body onload="alert('hey');">
<p>hello</p>
</body>
</html>
I can see the "hello" line but the Javascript doesn't work.
Interestingly, if I do a GetMapping for the Spring method (using URL params instead of POST data), the Javascript does work! Anyone know why this is? Why would a POST vs. GET in the controller affect whether the Javascript loads or not? How can I force it to load? I really don't want to have to use a GET here.
UPDATE: Wanted to note that the POST method is being invoked by an ajax call via Javascript. That could make a difference.
I have a jersey client class which is making a put request to a rest.
//JerseyClient
public void putRequest() throws Exception{
reloadUri();
Response response = target.request(MediaType.APPLICATION_JSON)
.accept("application/json;charset=UTF-8")
.header("Content-Type", "application/json")
.header("Authorization", "Basic OTA1MzAwNjY3MDg2OjZ4dDg5dk50VXdCbg==")
.put(Entity.entity(sub, MediaType.APPLICATION_JSON),Response.class);
System.out.println(response);
if(response.getStatus() == 200) {
System.out.println("put request using Json is Success");
}
}
It's working fine, but I wanted to call this function with a button click. And this button is placed on one of my jsp file. So, is there a way to call this request inside that jsp file when button clicked.And redirect the page into new jsp according to response of rest.
No directly by the jsp. If you include this code in the jsp, it will be executed while parsing the jsp page in the server.
You should include it in a Java component which will be called by a Servlet (or controller, filter, etc...). The button in your jsp will make a call to the URL which executes that component, and is there where you must do whatever you need with the result.
If you want to execute directly in the jsp while clicking the button, you must make it using javascript in client side.
You may call this method using URL reference:
define a path annotation for method:
#Path("/PATH")
#GET// or #POST
public void putRequest() throws Exception{
...
}
And then, from you jsp page you can define the button to redirect to this URL to initiate the above method.
You may read more about jersey annotations here.
All:
I have an issue with a project I am working on using C# MVC4
In the project, I am accepting a URL and other parameters from a user, then do some processing and send the result of the processing to the URL provided by the user.
The result is being sent using the following code:
var context = HttpContext.Current;
context.Response.Write("<html><head>");
context.Response.Write("</head><body>");
context.Response.Write(string.Format("<form name=\"myform\" method=\"post\" action=\"{0}\" >", postUrl));
context.Response.Write("</form>");
context.Response.Write("<script type=\"text/javascript\">document.myform.submit();</script></body></html>");
context.Response.Write("</body>");
context.Response.Flush();
context.Response.Clear();
context.ApplicationInstance.CompleteRequest();
Whenever a user attempts an XSS like passing a url value of javascript%3aalert('xss')%2f%2f, the JavaScript runs and the pop up shows up.
I've tried Antixss.HtmlEncode() to encode the URL before passing it into string.Format but still doesn't work. I've tried Antixss.UrlEncode() also, but this gives error as the form doesn't submit to the URL.
Please help me out, Is there something I am missing? What else can I do?
Thanks in advance.
You will need a three pronged approach to solve this issue.
Preventing XSS injection:
Note that if a user injected the url value
" /> <script>alert('xss')</script>
this would also leave you vulnerable:
<form name="myform" method="post" action="" /> <script>alert('xss')</script>" >
Therefore you should use the HttpUtility.HtmlAttributeEncode function to solve this one.
However, don't stop there. As noted, you should project against javascript: style URLs. For this I would ensure that the URL begins with http:// or https://. If not, throw a SecurityException which you should be logging and handling server-side, and showing the user a custom error page.
Finally, you want to protect against Open Redirect Vulnerabilities. This is to stop phishing attacks by redirecting users to other domains. Again, use a whitelist approach and ensure that the domain redirected to is one of your own. Be careful on the parsing here, as it is easy to get it wrong - a URL of http://example.org?http://example.com will pass the validation filter for example.com on many badly written validation routines. I recommend using the Uri object in .NET and retrieving the domain through that rather than rolling your own string functions.
You could also check if the URL is a relative URL, and allow it if acceptable. Use something like this function which uses a built in .NET library to ensure that it is relative or not.
Just a thought - try putting this script in rather than just document.myform.submit (and remove the form's action property):
if("{0}".indexOf('http') !== 0) {
//this is some sort of injection, or it's pointing at something on your server. Should cover http and https.
//Specifically, it makes sure that the url starts with 'http' - so a 'javascript' url isn't going to work.
} else {
document.myform.action="{0}"
document.myform.submit();
}
There is more you could do, but this should help.
Since you are adding the postUrl as an attribute "action" of the form tag, you can try using HtmlAttributeEncode method in the HttpUtility
[ValidateInput(false)]
public ActionResult Test(string url)
{
var context = System.Web.HttpContext.Current;
context.Response.Write("<html><head>");
context.Response.Write("</head><body>");
context.Response.Write(string.Format("<form name=\"myform\" method=\"post\" action=\"{0}\" >", HttpUtility.HtmlAttributeEncode(url)));
context.Response.Write("</form>");
context.Response.Write("<script type=\"text/javascript\">document.myform.submit();</script></body></html>");
context.Response.Write("</body>");
context.Response.Flush();
context.Response.Clear();
context.ApplicationInstance.CompleteRequest();
return null;
}
http://localhost:39200/home/test?url=https%3A%2F%2Fwww.google.com - Worked
http://localhost:39200/home/test?url=%3Cscript%3Ealert(%27test%27)%3C%2Fscript%3E - Worked(Did not show alert)
It is always good practice to Validate the user input against a white list of inputs, to prevent XSS exploits.
try using HttpUtility.UrlEncode
something like Response.Write(HttpUtility.UrlEncode(urlString));
see How To: Prevent Cross-Site Scripting in ASP.NET for more steps =)
I am working on creating a RESTful API that supports cross-domain requests, JSON/JSONP support, and the main HTTP method (PUT/GET/POST/DELETE). Now while will be easy to accessing this API through server side code , it would nice to exposed it to javascript. From what I can tell, when doing a JSONP requests with jQuery, it only supports the GET method. Is there a way to do a JSONP request using POST/PUT/DELETE?
Ideally I would like a way to do this from within jQuery (through a plugin if the core does not support this), but I will take a plain javascript solution too. Any links to working code or how to code it would be helpful, thanks.
Actually - there is a way to support POST requests.
And there is no need in a PROXI server - just a small utility HTML page that is described bellow.
Here's how you get Effectively a POST cross-domain call, including attached files and multi-part and all :)
Here first are the steps in understanding the idea, after that - find an implementation sample.
How JSONP of jQuery is implemented, and why doesn't it support POST requests?
While the traditional JSONP is implemented by creating a script element and appending it into the DOM - what results inforcing the browser to fire an HTTP request to retrieve the source for the tag, and then execute it as JavaScript, the HTTP request that the browser fires is simple GET.
What is not limited to GET requests?
A FORM. Submit the FORM while specifing action the cross-domain server.
A FORM tag can be created completely using a script, populated with all fields using script, set all necessary attributes, injected into the DOM, and then submitted - all using script.
But how can we submit a FORM without refreshing the page?
We specify the target the form to an IFRAME in the same page.
An IFRAME can also be created, set, named and injected to the DOM using script.
But How can we hide this work from the user?
We'll contain both FORM and IFRAME in a hidden DIV using style="display:none"
(and here's the most complicated part of the technique, be patient)
But IFRAME from another domain cannot call a callback on it's top-level document. How to overcome that?
Indeed , if a response from FORM submit is a page from another domain, any script communication between the top-level page and the page in the IFRAME results in "access denied". So the server cannot callback using a script. What can the server can do? redirect. The server may redirect to any page - including pages in the same domain as the top-level document - pages that can invoke the callback for us.
How can a server redirect?
two ways:
Using client side script like <Script>location.href = 'some-url'</script>
Using HTTP-Header. See: http://www.webconfs.com/how-to-redirect-a-webpage.php
So I end up with another page? How does it help me?
This is a simple utility page that will be used from all cross-domain calls. Actually, this page is in-fact a kind of a proxi, but it is not a server, but a simple and static HTML page, that anybody with notepad and a browser can use.
All this page has to do is invoke the callback on the top-level document, with the response-data from the server. Client-Side scripting has access to all URL parts, and the server can put it's response there encoded as part of it, as well as the name of the callback that has to be invoked. Means - this page can be a static and HTML page, and does not have to be a dynamic server-side page :)
This utility page will take the information from the URL it runs in - specifically in my implementation bellow - the Query-String parameters (or you can write your own implementation using anchor-ID - i.e the part of a url right to the "#" sign). And since this page is static - it can be even allowed to be cached :)
Won't adding for every POST request a DIV, a SCRIPT and an IFRAME eventually leak memory?
If you leave it in the page - it will. If you clean after you - it will not. All we have to do is give an ID to the DIV that we can use to celan-up the DIV and the FORM and IFRAME inside it whenever the response arrives from the server, or times out.
What do we get?
Effectively a POST cross-domain call, including attached files and multi-part and all :)
What are the limits?
The server response is limited to whatever fits into a redirection.
The server must ALWAYS return a REDIRECT to a POST requests. That include 404 and 500 errors.
Alternatively - create a timeout on the client just before firing the request, so you'll have a chance to detect requests that have not returned.
not everybody can understand all this and all the stages involved. it's a kind of an infrastructure level work, but once you get it running - it rocks :)
Can I use it for PUT and DELETE calls?
FORM tag does not PUT and DELETE.
But that's better then nothing :)
Ok, got the concept. How is it done technically?
What I do is:
I create the DIV, style it as invisible, and append it to the DOM. I also give it an ID that I can clean it up from the DOM after the server response has arrived (the same way JQuery cleans it's JSONP SCRIPT tasgs - but the DIV).
Then I compose a string that contains both IFRAME and FORM - with all attributes, properties and input fields, and inject it into the invisible DIV. it is important to inject this string into the DIV only AFTER the div is in the DOM. If not - it will not work on all browsers.
After that - I obtain a reference to the FORM and submit it.
Just remember one line before that - to set a Timeout callback in case the server does not respond, or responds in a wrong way.
The callback function contains the clean-up code. It is also called by timer in case of a response-timeout (and cleans it's timeout-timer when a server response arrives).
Show me the code!
The code snippet bellow is totally "neutral" on "pure" javascript, and declares whatever utility it needs. Just for simplification of explaining the idea - it all runs on the global scope, however it should be a little more sophisticated...
Organize it in functions as you may and parameterize what you need - but make sure that all parts that need to see each other run on the same scope :)
For this example - assume the client runs on http://samedomain.com and the server runs on http://crossdomain.com.
The script code on the top-level document
//declare the Async-call callback function on the global scope
function myAsyncJSONPCallback(data){
//clean up
var e = document.getElementById(id);
if (e) e.parentNode.removeChild(e);
clearTimeout(timeout);
if (data && data.error){
//handle errors & TIMEOUTS
//...
return;
}
//use data
//...
}
var serverUrl = "http://crossdomain.com/server/page"
, params = { param1 : "value of param 1" //I assume this value to be passed
, param2 : "value of param 2" //here I just declare it...
, callback: "myAsyncJSONPCallback"
}
, clientUtilityUrl = "http://samedomain.com/utils/postResponse.html"
, id = "some-unique-id"// unique Request ID. You can generate it your own way
, div = document.createElement("DIV") //this is where the actual work start!
, HTML = [ "<IFRAME name='ifr_",id,"'></IFRAME>"
, "<form target='ifr_",id,"' method='POST' action='",serverUrl
, "' id='frm_",id,"' enctype='multipart/form-data'>"
]
, each, pval, timeout;
//augment utility func to make the array a "StringBuffer" - see usage bellow
HTML.add = function(){
for (var i =0; i < arguments.length; i++)
this[this.length] = arguments[i];
}
//add rurl to the params object - part of infrastructure work
params.rurl = clientUtilityUrl //ABSOLUTE URL to the utility page must be on
//the SAME DOMAIN as page that makes the request
//add all params to composed string of FORM and IFRAME inside the FORM tag
for(each in params){
pval = params[each].toString().replace(/\"/g,""");//assure: that " mark will not break
HTML.add("<input name='",each,"' value='",pval,"'/>"); // the composed string
}
//close FORM tag in composed string and put all parts together
HTML.add("</form>");
HTML = HTML.join(""); //Now the composed HTML string ready :)
//prepare the DIV
div.id = id; // this ID is used to clean-up once the response has come, or timeout is detected
div.style.display = "none"; //assure the DIV will not influence UI
//TRICKY: append the DIV to the DOM and *ONLY THEN* inject the HTML in it
// for some reason it works in all browsers only this way. Injecting the DIV as part
// of a composed string did not always work for me
document.body.appendChild(div);
div.innerHTML = HTML;
//TRICKY: note that myAsyncJSONPCallback must see the 'timeout' variable
timeout = setTimeout("myAsyncJSONPCallback({error:'TIMEOUT'})",4000);
document.getElementById("frm_"+id+).submit();
The server on the cross-domain
The response from the server is expected to be a REDIRECTION, either by HTTP-Header or by writing a SCRIPT tag. (redirection is better, SCRIPT tag is easier to debug with JS breakpoints).
Here's the example of the header, assuming the rurl value from above
Location: http://samedomain.com/HTML/page?callback=myAsyncJSONPCallback&data=whatever_the_server_has_to_return
Note that
the value of the data argument can be a JavaScript Object-Literal or JSON expression, however it better be url-encoded.
the length of the server response is limited to the length of a URL a browser can process.
Also - in my system the server has a default value for the rurl so that this parameter is optional. But you can do that only if your client-application and server-application are coupled.
APIs to emit redirection header:
http://www.webconfs.com/how-to-redirect-a-webpage.php
Alternatively, you can have the server write as a response the following:
<script>
location.href="http://samedomain.com/HTML/page?callback=myAsyncJSONPCallback&data=whatever_the_server_has_to_return"
</script>
But HTTP-Headers would be considered more clean ;)
The utility page on the same domain as the top-level document
I use the same utility page as rurl for all my post requests: all it does is take the name of the callback and the parameters from the Query-String using client side code, and call it on the parent document. It can do it ONLY when this page runs in the EXACT same domain as the page that fired the request! Important: Unlike cookies - subdomains do not count!! It has to he the exact same domain.
It's also make it more efficient if this utility page contains no references to other resources -including JS libraries. So this page is plain JavaScript. But you can implement it however you like.
Here's the responder page that I use, who's URL is found in the rurl of the POST request (in the example: http://samedomain.com/utils/postResponse.html )
<html><head>
<script type="text/javascript">
//parse and organize all QS parameters in a more comfortable way
var params = {};
if (location.search.length > 1) {
var i, arr = location.search.substr(1).split("&");
for (i = 0; i < arr.length; i++) {
arr[i] = arr[i].split("=");
params[arr[i][0]] = unescape(arr[i][1]);
}
}
//support server answer as JavaScript Object-Literals or JSON:
// evaluate the data expression
try {
eval("params.data = " + params.data);
} catch (e) {
params.data = {error: "server response failed with evaluation error: " + e.message
,data : params.data
}
}
//invoke the callback on the parent
try{
window.parent[ params.callback ](params.data || "no-data-returned");
}catch(e){
//if something went wrong - at least let's learn about it in the
// console (in addition to the timeout)
throw "Problem in passing POST response to host page: \n\n" + e.message;
}
</script>
</head><body></body></html>
It's not much automation and 'ready-made' library like jQuery and involes some 'manual' work - but it has the charm :)
If you're a keen fan of ready-made libraries - you can also check on Dojo Toolkit that when last I checked (about a year ago) - had their own implementation for the same mechanism.
http://dojotoolkit.org/
Good luck buddy, I hope it helps...
Is there a way to do a JSONP request using POST/PUT/DELETE?
No there isn't.
No. Consider what JSONP is: an injection of a new <script> tag in the document. The browser performs a GET request to pull the script pointed to by the src attribute. There's no way to specify any other HTTP verb when doing this.
Rather than banging our heads with JSONP method, that actually won't
support POST method by default, we can go for CORS .That will provide no big changes in the conventional way of programming. By simple Jquery Ajax call we can go with cross domains.
In CORS method, you have to add headers in server side scripting file, or in the server itself(in remote domain), for enabling this access. This is much reliable, since we can prevent/restrict the domains making unwanted calls.
It can be found in detail in wikipedia page.
My question is if there is a way to simply post process wicket HTML response?
What I want to do is to apply some DOM transformations to the generated HTML using Rhino (http://www.mozilla.org/rhino/) and jQuery.
Anyone ever thought about it? Any suggestions where to start?
Best,
Maciej Wrzalik
OK, I've got this:
public class MyRequestCycle extends WebRequestCycle {
public MyRequestCycle(WebApplication application, WebRequest request, WebResponse response) {
super(application, request, response);
}
#Override
protected void onEndRequest() {
String responseString = response.toString();
//String newResponseString = process(responseString);
//replace old response content with the newResponseString
super.onEndRequest();
}
}
In method onEndRequest the string responseString contains HTML code that I'm going to alter some way using Rhino, Envjs and jQuery but the question is how can I replace the old response content with the new one?
Envjs emulates the browser environment under Rhino, and specifically allows you to do DOM manipulation server-side using jQuery. I have used it before in my projects, and have had good success. Relevant resources:
http://www.envjs.com/
http://ejohn.org/blog/bringing-the-browser-to-the-server/
If you want the post-processing done on the server, your best bet is likely to implement a Servlet Filter which modifies the response before it goes to the client.
As you're working on the rendered HTML, this has nothing particular to do with Wicket, and could be applied to html generated by any Java framework.
As suggested, a normal Java EE filter would work fine, if there's nothing Wicket-specific that you need for the processing.
But if you want to do it inside Wicket, for some reason or other, I suppose you could create your own RequestCycle implementation (MyRequestCycle extends WebRequestCycle) and do the processing there (perhaps by overriding onEndRequest and/or getWebResponse).
To use a custom RequestCycle, override newRequestCycle in your Application class:
#Override
public RequestCycle newRequestCycle(Request request, Response response) {
return new MyRequestCycle(this, (WebRequest) request, response);
}
I'm using custom a RequestCycle for a couple of things (e.g. this) myself—it's simple and straightforward—but I'm not 100% sure if it fits your needs here. (My Wicket experience is still somewhat limited.)