Develop Reference

javascript - Getting the iframe's URL after reload of iframe content doesn't work in Chrome and Safari

I'm working on a phaser game that's to be embedded in a website via iframe. The game supports multiple languages, so we've taken to using the site the game was accessed from as an indicator (phaser-game.com/ru would be in Russian, phaser-game.com/ar would be in Arabic, etc).
Here's the code so far (fired via window.addEventListener('load', getDomainSetLanguage);:
function getDomainSetLanguage()
{
let url = (window.location !== window.parent.location) ? document.referrer : document.location.href;
console.log('url = ' + url);
for (let i = 0; i < COUNTRIES_DOMAIN.length; i++)
{
if (url.indexOf(COUNTRIES_DOMAIN[i].URL) >= 0)
{
DOMAIN_ID = COUNTRIES_DOMAIN[i].ID;
LANGUAGE_ID = COUNTRIES_DOMAIN[i].LANGUAGE_ID;
break;
}
}
if (DOMAIN_ID === -1)
{
DOMAIN_ID = 1;
}
if (LANGUAGE_ID === -1)
{
LANGUAGE_ID = 1;
}
console.log('DOMAIN_ID = ' + DOMAIN_ID + "; LANGUAGE_ID = " + LANGUAGE_ID);
}
Now this works fine, on the surface. However, the game does trigger a reload every now and then, and when the game comes back, it now gets it's own URL, not the parent's / iframe's.
This has the result of the game language defaulting to English.
Note that this only occurs in Chrome and Safari. FireFox works just fine.
Is there something I'm missing? Or is there anything else I can try?
I've tried logging the values of document.referrer and document.location.href, but I'm just getting browser errors about permissions and stuff and the game defaults to English.
I read from here that Chrome (and possibly Safari) doesn't fire the onload function of objects in the iframe, but I'm not sure if this applies to me, as I have a lot of other functions tied to onload that do work.
It should be mentioned that I cannot modify the iframe itself, so any solution must be from the game itself.
Thanks!

let url = (window.location !== window.parent.location) ? document.referrer : document.location.href;
This line from your code makes it so that when you're inside of an iframe, document.referrer is used as the URL to determine the language from.
As per the MDN page on Document.referrer:
The Document.referrer property returns the URI of the page that linked to this page.
Inside an <iframe>, the Document.referrer will initially be set to the same value as the href of the parent window's Window.location.
This means it will work on initial load just fine, as you've experienced.
As far as I can tell, the specification isn't explicit about how to handle reloading. This is probably the cause of the differences in browser behaviour. It isn't too crazy to think that is should be empty after a reload, as it wasn't loaded from the parent page that time around.
An alternate solution would be to use window.parent.location.href, which always refers to the URL of the iframe's parent window (read more in Difference between document.referrer and window.parent.location.href).
Your line of code could look something like this:
// if parent and child href are equal, using either yields the same result
// if there is no parent, window.parent will be equal to window
// therefore, the conditional statement isn't necessary
let url = window.parent.location.href;

Restore native Window method

For a script I'm writing, I'd like to use the native window.open method. However, a script already loaded to which I don't have access, overwrites the global window.open method with a boolean (ouch).
I know how to restore the methods on the Document (via HTMLDocument.prototype), but I don't know how to restore them on the Window, as I can't seem to find the equivalent for that to Window. Window.prototype.open does not exist for example.
I have tried creating an iframe, and getting the open method from that contentWindow in the iframe, but the browser will block opening windows using open because it was probably created in another origin. Neither delete open; does work because open was defined using var in the globally loaded script.
So, how can I restore the open method, defined as 'native code' in Chrome?
I know there are similar questions around, but actually the main question is:
Is there a equivalent of HTMLDocument for the Window object?

I've found this question and the accepted answer (using an iframe) could be used in your case.
The only issue is you can only use the retrieved version of window.open as long as the iframe is still in your document.
function customOpen() {
// local variables definitions :
var url = "https://stackoverflow.com", iframe, _window;
// creating an iframe and getting its version of window.open :
iframe = document.createElement("iframe");
document.documentElement.appendChild(iframe);
_window = iframe.contentWindow;
// storing it in our window object
window.nativeOpen = _window.open;
try {
window.open(url);
} catch (e) {
console.warn(e); // checking that window.open is still broken
}
window.nativeOpen(url);
// deleting the iframe :
document.documentElement.removeChild(iframe);
}
document.getElementById("button").addEventListener("click", customOpen);
Another JSFiddle
Keeping the workaround answer in case someone needs it :
Can you execute a custom script prior to the execution of the script that redefines window.open? If so, you could create a copy of the window.open in another global variable.
It could look like this :
1. First : a backup script
window.nativeOpen = window.open;
2. Then, whatever the window.open overwriting script does :
window.open = false; // who does that, seriously?
3. Your window opening script, that'll use your window.open copy :
function customOpen() {
var url = "https://stackoverflow.com";
try {
window.open(url);
} catch (e) {
console.warn(e);
}
window.nativeOpen(url);
}
JSFiddle example

How to determine if JS code executes in iframe? [duplicate]

I am writing an iframe based facebook app. Now I want to use the same html page to render the normal website as well as the canvas page within facebook. I want to know if I can determine whether the page has been loaded inside the iframe or directly in the browser?

Browsers can block access to window.top due to same origin policy. IE bugs also take place. Here's the working code:
function inIframe () {
try {
return window.self !== window.top;
} catch (e) {
return true;
}
}
top and self are both window objects (along with parent), so you're seeing if your window is the top window.

When in an iframe on the same origin as the parent, the window.frameElement method returns the element (e.g. iframe or object) in which the window is embedded. Otherwise, if browsing in a top-level context, or if the parent and the child frame have different origins, it will evaluate to null.
window.frameElement
? 'embedded in iframe or object'
: 'not embedded or cross-origin'
This is an HTML Standard with basic support in all modern browsers.

if ( window !== window.parent )
{
// The page is in an iframe
}
else
{
// The page is not in an iframe
}

I'm not sure how this example works for older Web browsers but I use this for IE, Firefox and Chrome without an issue:
var iFrameDetection = (window === window.parent) ? false : true;

RoBorg is correct, but I wanted to add a side note.
In IE7/IE8 when Microsoft added Tabs to their browser they broke one thing that will cause havoc with your JS if you are not careful.
Imagine this page layout:
MainPage.html
IframedPage1.html (named "foo")
IframedPage2.html (named "bar")
IframedPage3.html (named "baz")
Now in frame "baz" you click a link (no target, loads in the "baz" frame) it works fine.
If the page that gets loaded, lets call it special.html, uses JS to check if "it" has a parent frame named "bar" it will return true (expected).
Now lets say that the special.html page when it loads, checks the parent frame (for existence and its name, and if it is "bar" it reloads itself in the bar frame. e.g.
if(window.parent && window.parent.name == 'bar'){
window.parent.location = self.location;
}
So far so good. Now comes the bug.
Lets say instead of clicking on the original link like normal, and loading the special.html page in the "baz" frame, you middle-clicked it or chose to open it in a new Tab.
When that new tab loads (with no parent frames at all!) IE will enter an endless loop of page loading! because IE "copies over" the frame structure in JavaScript such that the new tab DOES have a parent, and that parent HAS the name "bar".
The good news, is that checking:
if(self == top){
//this returns true!
}
in that new tab does return true, and thus you can test for this odd condition.

The accepted answer didn't work for me inside the content script of a Firefox 6.0 Extension (Addon-SDK 1.0): Firefox executes the content script in each: the top-level window and in all iframes.
Inside the content script I get the following results:
(window !== window.top) : false
(window.self !== window.top) : true
The strange thing about this output is that it's always the same regardless whether the code is run inside an iframe or the top-level window.
On the other hand Google Chrome seems to execute my content script only once within the top-level window, so the above wouldn't work at all.
What finally worked for me in a content script in both browsers is this:
console.log(window.frames.length + ':' + parent.frames.length);
Without iframes this prints 0:0, in a top-level window containing one frame it prints 1:1, and in the only iframe of a document it prints 0:1.
This allows my extension to determine in both browsers if there are any iframes present, and additionally in Firefox if it is run inside one of the iframes.

I'm using this:
var isIframe = (self.frameElement && (self.frameElement+"").indexOf("HTMLIFrameElement") > -1);

Use this javascript function as an example on how to accomplish this.
function isNoIframeOrIframeInMyHost() {
// Validation: it must be loaded as the top page, or if it is loaded in an iframe
// then it must be embedded in my own domain.
// Info: IF top.location.href is not accessible THEN it is embedded in an iframe
// and the domains are different.
var myresult = true;
try {
var tophref = top.location.href;
var tophostname = top.location.hostname.toString();
var myhref = location.href;
if (tophref === myhref) {
myresult = true;
} else if (tophostname !== "www.yourdomain.com") {
myresult = false;
}
} catch (error) {
// error is a permission error that top.location.href is not accessible
// (which means parent domain <> iframe domain)!
myresult = false;
}
return myresult;
}

Best-for-now Legacy Browser Frame Breaking Script
The other solutions did not worked for me. This one works on all browsers:
One way to defend against clickjacking is to include a "frame-breaker" script in each page that should not be framed. The following methodology will prevent a webpage from being framed even in legacy browsers, that do not support the X-Frame-Options-Header.
In the document HEAD element, add the following:
<style id="antiClickjack">body{display:none !important;}</style>
First apply an ID to the style element itself:
<script type="text/javascript">
if (self === top) {
var antiClickjack = document.getElementById("antiClickjack");
antiClickjack.parentNode.removeChild(antiClickjack);
} else {
top.location = self.location;
}
</script>
This way, everything can be in the document HEAD and you only need one method/taglib in your API.
Reference: https://www.codemagi.com/blog/post/194

I actually used to check window.parent and it worked for me, but lately window is a cyclic object and always has a parent key, iframe or no iframe.
As the comments suggest hard comparing with window.parent works. Not sure if this will work if iframe is exactly the same webpage as parent.
window === window.parent;

Since you are asking in the context of a facebook app, you might want to consider detecting this at the server when the initial request is made. Facebook will pass along a bunch of querystring data including the fb_sig_user key if it is called from an iframe.
Since you probably need to check and use this data anyway in your app, use it to determine the the appropriate context to render.

function amiLoadedInIFrame() {
try {
// Introduce a new propery in window.top
window.top.dummyAttribute = true;
// If window.dummyAttribute is there.. then window and window.top are same intances
return !window.dummyAttribute;
} catch(e) {
// Exception will be raised when the top is in different domain
return true;
}
}

Following on what #magnoz was saying, here is a code implementation of his answer.
constructor() {
let windowLen = window.frames.length;
let parentLen = parent.frames.length;
if (windowLen == 0 && parentLen >= 1) {
this.isInIframe = true
console.log('Is in Iframe!')
} else {
console.log('Is in main window!')
}
}

It's an ancient piece of code that I've used a few times:
if (parent.location.href == self.location.href) {
window.location.href = 'https://www.facebook.com/pagename?v=app_1357902468';
}

If you want to know if the user is accessing your app from facebook page tab or canvas check for the Signed Request. If you don't get it, probably the user is not accessing from facebook.
To make sure confirm the signed_request fields structure and fields content.
With the php-sdk you can get the Signed Request like this:
$signed_request = $facebook->getSignedRequest();
You can read more about Signed Request here:
https://developers.facebook.com/docs/reference/php/facebook-getSignedRequest/
and here:
https://developers.facebook.com/docs/reference/login/signed-request/

This ended being the simplest solution for me.
<p id="demofsdfsdfs"></p>
<script>
if(window.self !== window.top) {
//run this code if in an iframe
document.getElementById("demofsdfsdfs").innerHTML = "in frame";
}else{
//run code if not in an iframe
document.getElementById("demofsdfsdfs").innerHTML = "no frame";
}
</script>

if (window.frames.length != parent.frames.length) { page loaded in iframe }
But only if number of iframes differs in your page and page who are loading you in iframe. Make no iframe in your page to have 100% guarantee of result of this code

Write this javascript in each page
if (self == top)
{ window.location = "Home.aspx"; }
Then it will automatically redirects to home page.

Functions() out of iframe? [duplicate]

This question already has an answer here:
Closed 10 years ago.
Possible Duplicate:
Is it possible to call Javascript function in parent document from JS in iframe?
I have a main.php page.
This contains an iframe which src is random.php.
How can I have script in the main.php with a random function, random(), and let random.php use that function?

If you are working with HTML5, you can use the postMessage() function..
here is a nice demo:
http://html5demos.com/postmessage
UPDATE
The idea is to postMessage to the iframe window object, each window is listening to the message event like so:
In your main.php:
window.addEventListener("message", function(e){
var data = e.data; // data can be any object for example { type: 'random', payload: {}... }
switch(data.type){
case 'random':
// do somthing here with the payload...
break;
}
});
in your iframe (random.php):
window.parent.postMessage({ type: 'random', payload: {...} });

You can call the function random in the page that contains the iframe using window.parent.random(). If you want to do the opposite, namely calling a function in an (i)frame from a containing page, you should use [DOM Reference to frame].contentWindow.random() instead.
↪ More information about window.parent at the Mozilla Developer wiki
If random.php is at a different domain, you can't do this because of the Same Origin Policy. If that's the case, you can use HTML5 postMessage to transfer information across pages*. This does not allow you to directly call functions of a different domain's JavaScript, however.
* See Can I use for browser support information

contentDocument.document returning undefined [duplicate]

I'm trying to get the document object of an iframe, but none of the examples I've googled seem to help. My code looks like this:
<html>
<head>
<script>
function myFunc(){
alert("I'm getting this far");
var doc=document.getElementById("frame").document;
alert("document is undefined: "+doc);
}
</script>
</head>
<body>
<iframe src="http://www.google.com/ncr" id="frame" width="100%" height="100%" onload="myFync()"></iframe>
</body>
</html>
I have tested that I am able to obtain the iframe object, but .document doesn't work, neither does .contentDocument and I think I've tested some other options too, but all of them return undefined, even examples that are supposed to have worked but they don't work for me. So I already have the iframe object, now all I want is it's document object. I have tested this on Firefox and Chrome to no avail.

Try the following
var doc=document.getElementById("frame").contentDocument;
// Earlier versions of IE or IE8+ where !DOCTYPE is not specified
var doc=document.getElementById("frame").contentWindow.document;
Note: AndyE pointed out that contentWindow is supported by all major browsers so this may be the best way to go.
http://help.dottoro.com/ljctglqj.php
Note2: In this sample you won't be able to access the document via any means. The reason is you can't access the document of an iframe with a different origin because it violates the "Same Origin" security policy
http://javascript.info/tutorial/same-origin-security-policy

This is the code I use:
var ifrm = document.getElementById('myFrame');
ifrm = (ifrm.contentWindow) ? ifrm.contentWindow : (ifrm.contentDocument.document) ? ifrm.contentDocument.document : ifrm.contentDocument;
ifrm.document.open();
ifrm.document.write('Hello World!');
ifrm.document.close();
contentWindow vs. contentDocument
IE (Win) and Mozilla (1.7) will return the window object inside the
iframe with oIFrame.contentWindow.
Safari (1.2.4) doesn't understand that property, but does have
oIframe.contentDocument, which points to the document object inside
the iframe.
To make it even more complicated, Opera 7 uses
oIframe.contentDocument, but it points to the window object of the
iframe. Because Safari has no way to directly access the window object
of an iframe element via standard DOM (or does it?), our fully
modern-cross-browser-compatible code will only be able to access the
document within the iframe.

For even more robustness:
function getIframeWindow(iframe_object) {
var doc;
if (iframe_object.contentWindow) {
return iframe_object.contentWindow;
}
if (iframe_object.window) {
return iframe_object.window;
}
if (!doc && iframe_object.contentDocument) {
doc = iframe_object.contentDocument;
}
if (!doc && iframe_object.document) {
doc = iframe_object.document;
}
if (doc && doc.defaultView) {
return doc.defaultView;
}
if (doc && doc.parentWindow) {
return doc.parentWindow;
}
return undefined;
}
and
...
var el = document.getElementById('targetFrame');
var frame_win = getIframeWindow(el);
if (frame_win) {
frame_win.targetFunction();
...
}
...

In my case, it was due to Same Origin policies. To explain it further, MDN states the following:
If the iframe and the iframe's parent document are Same Origin, returns a Document (that is, the active document in the inline frame's nested browsing context), else returns null.