问题
(Rewording the question as there were very few views otherwise).
I want to build a widget that others can include on their website, and the widget itself will be hosted on my website. I am aware of just one method to build widgets that can be embedded on other websites: The website that wants to embedd the widget sources a javascript from my site, which does "document.write" on the page. Something like:
<script language="javascript" src="http://www.my-website-that-will-host-the-widget.com/javascript-emitter.php?id=1234&width=200&bordercolor=000000&bg=ffffff&textcolor=000000"></script>
Now, I want to make a particular widget accessible from only particular domains. For this, I want to know the URL of the page that is embedding my widget reliably . No-one should be able to spoof it. For example, if I have an explicit variable in the embedding code, people can change it.
How do I do it? (I also want that there minimal code to write for the person who is embedding my widget).
regards,
JP
Explanation 1:
Lets say I want to do this: If widget is accessed from 1.com, display A, else display B. How do I do it reliably. Thing is, "A" is something that should not be visible in the code unless the widget is accessed from 1.com. (Thus, if it is embedded in 2.com, I don't want to output if(location.href == 1.com) write(A) else write (B)
Note 1:
(As an aside, if someone feels my method is not good/efficient and can suggest better methods/tutorials, etc., that would be great help. Most google queries give you sites that explain how to build/obtain widget for "your site".... and usually point to websites that allow you to build widgets hosted with them, I want to understand how to build widgets that can be embedded by other websites from my site)
回答1:
In javascript on the client-side, you can use location.href to get the url of the current page:
var url = location.href;
If you do not want to output any javascript at all for a forbidden domain, in your php you can check the HTTP_REFERER header with the global variable $HTTP_REFERER. In your javascript-emitter.php script try this:
<?php
echo $HTTP_REFERER;
?>
However be warned that this is not always to be trusted: it is up to the client (the browser) to send the correct REFERER header. And of course if someone really wanted to include your widget on their site, they could easily request your javascript server-side spoofing the REFERER header - that is set it to something that's on your whitelist - before forwarding it to the client.
In short there's no way you can easily and absolutely block blacklisted sites from using your widget.
来源：https://stackoverflow.com/questions/4264938/how-to-get-url-of-embedding-page-for-a-javascript-widget