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Overwrite HTTP REFERER with PHP

I am trying to overwrite custom value to HTTP REFERRER. I got success with javascript but my client want in PHP and i need help in rewriting Javascript to PHP.
JS code :
var reff = ["http://example.com", "http://example.net", "http://example.org"];
var randomreff = reff[Math.floor(Math.random() * reff.length)];
delete window.document.referrer;
window.document.__defineGetter__("referrer", function () {
return randomreff;
});
document.write(document.referrer);
I am trying to rewrite this code in PHP or maybe finding a similar solution with PHP. i tried multiple way to do in PHP. these are some example.
PHP Try 1 :
$reff = new Arr("http://example.com", "http://example.net", "http://example.org");
$randomreff = get($reff, call_method($Math, "floor", to_number(call_method($Math, "random")) * to_number(get($reff, "length"))));
_delete(get($window, "document"), "referrer");
call_method(get($window, "document"), "__defineGetter__", "referrer", new Func(function() use (&$randomreff) {
return $randomreff;
}));
PHP with variable :
$var = 'var reff = ["http://example.com", "http://example.net", "http://example.org"];
var randomreff = reff[Math.floor(Math.random() * reff.length)];
delete window.document.referrer;
window.document.__defineGetter__("referrer", function () {
return randomreff;
});
';
PHP with header referer :
header("Referer: https://www.example.com/");
None of them worked. Help me to rewrite Javascript code or alternative solution with PHP.

You won't be able to do this with PHP exclusively. document.referrer is a DOM property that is set by the browser when the page loads by reading the referrer header on the request. Since the request is generated by the browser you can't really touch it with PHP since that is executed on the server and not in the browser, if you want to execute something in the browser you will need javascript.
In your examples you are just trying to run javascript-code from PHP it seems, and that just won't work. The last sample that sets the referrer-header will set it on the response back from the server, but as I said, referrer is a request variable so it will just be ignored.
The only thing you could do from PHP is to tell the browser to redirect to the page again (by setting the location-header), but as far as I know these days this won't reset the referral-header (if so then redirects from http to https for example would loose it all the time).
I'm not exactly sure are you trying to acomplish here. Setting document.referrer is only valid for the current page and won't affect what the next page sees. If executed early it might fool some tracking scripts at most.

window.location.href with POST instead of GET (or equivalent effect)

I'd like to reload a web page after supplying new parameters to it via POST in the same way as would be possible with an HTML form but from within JavaScript (inside an HTML page, but outside the context of a form).
Is this possible as HTTP POST instead of GET request (kind of XMLHttpRequest plus replace the currently shown document)? How could I replace the document, if XMLHttpRequest must be employed (instead of window.location.href)? The second question has been partially answered here.

The way I have always done this (with jquery) is this.
var $form=$(document.createElement('form')).css({display:'none'}).attr("method","POST").attr("action","URLHERE");
var $input=$(document.createElement('input')).attr('name','FIRST NAME HERE').val("FIRST VALUE HERE");
var $input2=$(document.createElemet('input')).attr('name','SECOND NAME HERE').val("SECOND VALUE HERE");
$form.append($input).append($input2);
$("body").append($form);
$form.submit();

Is it possible to delete an entire Webpage when the user navigates away?

If the user navigates off the webpage, is it possible to execute a php script?
I know that Javascript can be executed..
$(window).bind('beforeunload', function(){
return 'DataTest';
});
Cookies might work, but I am not sure how a listener could track an expired cookie, and then delete the correct webpage.
A sample file system is like this:
user0814HIFA9032RHBFAP3RU.php
user9IB83BFI19Y298RYBFWOF.php
index.php
listener.py
data.txt
Typically, to create the website, php writes to the data.txt and the Python listener picks up this change, and creates the file (user[numbers]). As you might think, these files stack up overtime and they need to be deleted.

The http protocol is stateless, therefore users simply can not "navigate away".
The browser requires a page, the server returns it, and the communication stops.
The server doesn't have reliable methods to know what the client will do with that page.

Disclaimer: I'm not sure, as Fox pointed out, that this is the right way to go in your case. I actuallly upvoted Fox's answer.
However, if you absolutely need to delete each page right after the user left it, use this:
$(window).bind('beforeunload', function() {
$.ajax('yourscript.php?currentUser=0814HIFA9032RHBFAP3RU');
});
Then in yourscript.php, put something like the following:
<?php
// load your userId (for example, with $_SESSION, but do what you want here)
$actualUser = $_SESSION['userId'];
// checks if the requested id to delete fits your actual current user's id
if (isset($_GET['currentUser'] && $_GET['currentUser'] == $actualUser)
{
$user = $_GET['currentUser'];
$file = 'user'.$user.'.php';
unlink($file);
}

How to execute some jQuery or JavaScript code after a redirect has completed

How can I execute jQuery/JS code as soon as a jQuery/JS redirect like...
$(location).attr('href','/target_path');
...or...
window.location.href = "/target_path";
...has finished loading the new page?
Specifically, I need to pass an alert message and insert it into and display it (enclosed in some HTML) on the new page.

You can't. Once the redirect happens you are no longer on that page. You can't execute code on a page you are no longer on. If you want the next page to do something then you need to pass, either by cookie or URL parameter, a flag that instructs it to do so.

It is impossible to tell JavaScript to execute some code after a redirect.
However you have different options:
Pass a string in the redirect URL and then do something on "ready"
Store some information in a cookie and then do something on "ready"
Store some data using DOM storage (namely sessionStorage) if you don't mind the smaller browser support

You can't do that in the page that's redirecting. You can read the referrer in the landing page (document.referrer), and then decide whether to display an alert based on that, though.

var x = "It's some text";
var loc = '/target_path';
loc += '?message=' + encodeURI(x);
The JS file on the new page can then look at the query string to see if a message is there, and do the required action if it's detected.
You can use window.location.search on the new page to see what's there, although I'd recommend hunting for a deparam function in a library to turn the query string into a more usable object.

Using PUT/POST/DELETE with JSONP and jQuery

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.