Develop Reference

How to show insecure content in iframe

In short , I'm developing a google chrome extension , when I add any url starting with http:// to source attribute to an iframe, I get a message like :
[blocked] The page at 'https://www.facebook.com/' was loaded over
HTTPS, but ran insecure content from 'http://youtu.be/m0QxDjRdIq4':
this content should also be loaded over HTTPS.
and I don't see the content in the iframe !
so how can I overcome this ?
what I want to achieve is that : I hide facebook adds , and in its place I added an iframe instead, I detect when the mouse is hovering over a link contained in a post, then I want to show the link's content in an iframe.
What are my possible alternatives? I don't need to enable showing insecure content in chrome because it is a chrome extension that I will publish!

It seems that the security limit is strict, so we need a way to work around that.
What if you could load the page using other means than an <iframe> and insert it into the page afterwards? There are multiple ways to do that, ranging from more practical to less realistic.
You can use the Chrome captureVisibleTab API to generate a screenshot of a website as an image, exactly what you need. It sounds like you need a visible tab to use this API, but you can actually specify any Chrome window as a target and you can create Chrome windows unfocused and hidden behind the edge of the screen.
If captureVisibleTab provides trouble in step 2, there is also pageCapture API to get an entire page as a single content object.
You can also use a server to create screenshots. Serve a simple application over HTTPS that uses PhantomJS to create a screenshot. An advantage of this approach is your server is likely to be much faster at screenshot generation. The disadvantage is you need to pay for the server.
You could also use xhr in your extension background process (which is not limited by the security limitation) to get the HTML. This wouldn't get any resources, but that could be a beneficial thing if you want a very quick if inaccurate screenshot. Just load HTML, parse and detect links to stylesheets, download them and inject those stylesheets into the HTML as <style> tags.
The resulting HTML can be injected to the <iframe> manually. You could even inject scripts and images this way, but that would be harder and less useful, since you need a quick screenshot of how the page looks like.
I think using built-in Chrome functionality for screenshots is the best bet, if only you can make the user experience good enough.

First and stupid way: change http in link on https. But youtube and I think many other sites don't allow to show their content in iframes. try it and you get Refused to display 'link' in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'.
Second and at least stupid way: remove protocol from link, like //youtu.be/m0QxDjRdIq4 and you get protocol, that on this page. But a situation similar to the previous.
Third way for youtube only: you can generate iframe with src like //www.youtube.com/embed/m0QxDjRdIq4 and user can see the video.
Fourth way, not for all sites: use site API's - not a best solution, but like a option.
Fifth way, but impossible (I think): try to get page's content with javascript and regenerate it in way, that you need.
Sixth way, needs powerfull server: create an service on your server, which will download pages and resend it to users. One problem - linear dependence server's power of requests.
Seventh way, I forgot that it's extension: you can open link in another tab/window, get it content, close tab/window and show content in tab that you need.
Eigth way, the best, I think: use YAHOO yql like this:
$.getJSON("https://query.yahooapis.com/v1/public/yql?q=select"
+"* from html where url='youtube.com/watch?v=m0QxDjRdIq4'"
+"&format=json&diagnostics=true&callback=?"
, function (data, textStatus, jqxhr) {
// process data
}
}
Demo on jsFiddle

Multiple og:image tags not being displayed by share dialog or update status box

I am currently working a new feature to allow users to select the thumbnail they would like to use when sharing an page on Facebook. The user should be able to use the Facebook widgets like the send dialog or share buttons as well as simply cutting and pasting the URL into their udpate status dialog on Facebook.
I have read much of the documentation, which seems to indicate that I simply need to add multiple og:image tags in the page being shared. I have done this and run the page through the linter so the cache gets updated.
When passing the page to the share.php directly, effectively removing any of my client side code and letting the dialog present what it is scraping, I am seeing 3 images from the page available.
I am not sure what I am doing wrong here.
Here is the linter result, the graph object, the sharer.php link and the page. Anyone have ideas of what I could be doing incorrectly?
I have confirmed that at least the og:title tag is being respected by the share dialog. I have also tested the size of the images, and included file extensions as suggested below.
I know this works because buzzfeed has the exact functionality I am going for. I have reduced my example down to only the core pieces I think should work. You can find the full source here.

Could it be the XML namespace in the top HTML tag?
In the BuzzFeed article, it's:
xmlns:og="http://opengraphprotocol.org/schema/"
In your page its:
xmlns:og="http://ogp.me/ns#"

On the Buzzfeed article, the content attributes in the og:image links point to named .jpg files, vs your links which do not have a filename/extension at the end.
It may be required to include a filename in the links, especially if it's basing image detection on the file extension.
EG:
Buzzfeed:
<meta property="og:image" content="http://s3-ak.buzzfeed.com/static/campaign_images/webdr02/2013/3/18/11/10-lifechanging-ways-to-make-your-day-more-effici-1-2774-1363621197-4_big.jpg" />
Yours:
<meta property="og:image" content="http://statics.stage3.cheezdev.com/mediumSquare/3845/4AC356E3/1"/>

After some tests, I guess it's a caching issue.
Looks like the sharer is caching the graph, using the og:url as a key, so that different querystrings in the sharer won't bypass the cache, if they do not impact the og:url value.
Obviously, the debug tool don't use such cache.
If I'm right (this is just an insight), you can either wait that the cache entry expires or try with a different og:url. Moreover, to ease the test, keep the new og:url equal to the new page location.

So funny story, I'm a developer at BuzzFeed and came across this while trying to figure out why our share dialogs suddenly stopped showing the thumbnail picker.
It looks like Facebook disabled the functionality. It briefly made a reappearance on 1/14/2014 but they introduced a bug that prevented sharing from any pages with multiple og:image tags defined. (See: https://developers.facebook.com/bugs/1393578360896606/)
They fixed the bug, but as of 1/22/2014 it still looks like the thumbnail picker is disabled.

The Sharer.php script on the Facebook site doesn't support all the OG tags as far as I know. The images are scraped from the page content itself, so if you want your three images to appear on the Sharer.php script, include them in your content.

Sharer.php has been officially deprecated by Facebook, so I wouldn't be surprised if certain functionality does not work with it. While it still works, it was always the simplest option and I'm guessing they never built the link image scraping from the og items into it.
I was able to find this article, which shows one way that you can specify exactly what images are available to the sharer.php share page. You can specify one (or multiple) images to share with a URL structure like the following:
http://www.facebook.com/sharer.php?s=100
&p[url]=http://bit.ly/myelection
&p[images][0]=http://election.gv.my/assets/vote.png
&p[title]=My customized title
&p[summary]=My customized summary

load external site and change its visualization

I'm trying to create a web page able to change a site visualization (.css or / and .js) in order to recreate the same live change capability offred by Firebug for Firefox or the Inspector of Chrome.
Here an image to better explain my task:
I have been able to visualize the other site inside my page using the iframe, but unfortunately it is not possible to change its visualization and access its elements due to the "same origin policy".
Is there a way to do this using the iframe or loading the external site inside another element?
Update:
Considering the answers the options should be:
create a php proxy page to load the target site and change visualization on it.
create a browser extention.
I've tried the first, even if it requires to install a web server (xampp), with a simple page calling the function file_get_contents('http://www.site.com');
The page is loaded but unfortunately missed some elements (like images) and it is only a static copy; it is not possible to go further in the site navigation.
Update 2:
Load the entire page via javascript could be the better solution (I don't konw how) if it is possible to live change the code but what about the possibility to interact with this "page copy" and transfer the interaction to the original one?
Scheme:
Explanation:
I've noticed Firebug extention can select and live edit any page element, even if they belong to the iframe which loads an external domain page.
What I'm looking for is a way to act like Firebug, get an element and change its style.
I'm trying to load the site into the iframe beacuse I wanted to create a toolbar above it to select my "visualization styles"; for example a button to makes titles bigger and red.
Anyway I'm open to any other methods suggestions.
Update 3:
I have found an extention for both FireFox and Chrome which is really close to my aim: "Stylish"
This add on allows to live change any site css proprerty and save it in order to reload them every time you'll visit the page.
Now my question is: How can I do the same creating a dedicated page to load and change visualization of a specific site?
FINAL EDIT:
In order to continue this question with a more relevant arguments I decided to ask a new one: create a php proxy page

No. Your solutions may be
to let your own site act as proxy so the same origin policy isn't triggered
to build an extension, which will be browser dependent (Firefox or Chrome) and which will require authorization and installation

I'm not sure if I understand what you want very well, but my feeling to ''trick'' this easier would probably to give very specific height and width to your first site (the iframe) and do a jQuery condition
If ($('body').width() == 500 && $('body').height() == 400 {
$('body').addClass('isiFrame');
}
Then, you only have to do your css .isiFrame .myCoolDivs {....}
You might have to use it on a document ready also, but that could be one way to trick it and since you're not doing it on resize (exepect if somebody's having his screen at this exact width and height at start)
The safer way would probably to create a master session using PHP but I cannot give you an example since it've been to long and echo the body class if the master_session or variable is equal to true
Hope it helped!

If you try to fight Same_origin_policy and try to fight it I am sure you won't get much success their.
Server Side
I would suggest you Handle this on server-side, grab the web-page and apply whatever styling and scripts you want, should be very easy!!
If you use Ruby on rails - Nokogiri gem can help you to parse html. And you can use standard library to 'get' a webpage.
Client Side
If you want to do this on client side, you need to write some jquery/javascript code, you can take following steps:
Get the webpage you want to display.
Grab the element's which include js/css files, remove them and your own.
Display the page in new Iframe present in your page.

See which page loads mine in iframe

I have a page that people load in an iframe (its like a widget they can put on their pages) and I want to see which pages are loading it... is this possible?

No, that's not reliably possible due to the Same origin policy.
(You would have to read the value of parent.location.href, which is not possible.)

Showing a demo of my CSS on any website

I have developed a small component which can be put in to any website. Now, I want to develop a code that could demonstrate how would my component look like on any website.
So, the person would come to my page and put in his URL and then my code should embed my custom JS/CSS in to the downloaded HTML and display it. Something like this.
Here, like the feedback tab, I want to show my component any where on that page.

Try a bookmarklet.
Create a piece of javascript that adds your code into the page such as the following:
javascript:(function(){var%20script=document.createElement('script');script.src='http://www.example.org/js/example.js';document.getElementsByTagName('head')[0].appendChild(script);})()
Add it as the href of a link like so:
Link Text Here
Tell your users to drag the link to their bookmark toolbar and click on it on different websites to try your code out.
Some examples: http://www.reclaimprivacy.org/, http://www.readability.com/bookmarklets

In the example you linked, they are requesting the page specified in the url querystring parameter on the server, and then doing more or less the following steps:
In the <head> tag they are adding a <base href="url" /> tag to the document. The base tag will make any relative links in the document treat the value in the href attribute as their root. This is how they are getting around broken css / images. (The base tag is supported by all browsers)
At the end of the document (IE the </body> tag) they are injecting the javascript that runs their demos.
They serve the modified HTML requested to the browser.
All of this is pretty straight forward in implementation. You could use regular expressions to match the <head> and </body> tags for steps 1 and 2 respectively. Depending on the server platform how you actually request the page will vary, but here are some links to get you started:
C# - HttpWebRequest object documentation
PHP - HttpRequest::send

Nathan's answer is the closest to how we have done the demo feature at WebEngage. To make such a demo functional, you'll need to create a Javascript widget that can be embedded on third party sites. syserr0r's answer on creating a bookmarklet is the simplest approach to do so. Our's is a JAVA backend and we use HttpClient to fetch the responses. As Nathan suggested, we parse the response, sanitize it and add our widget Javascript to the response. The widget JS code takes it on from there to render the Feedback tab and load a demo short survey.
Disclosure: I am a co-founder and ceo at WebEngage.

You can not do this with JQuery due to cross site scripting restrictions.
I suggest you write a PHP script that downloads the URL specified by the user and includes your widget code and then echo it back to the user.

I recommend using bookmarklets. I've made a bookmarklet generator for adding jQuery-enabled bookmarklets to a page to make development easier.
There's a caliper bookmarklet on the page that you can mess around with just to show an example of it working.
Full disclosure, this is something I've made, I'm not trying to be spammy as I think it's relevant: zbooks

You could make an iframe page, which loads their page in the iframe, and uses javascript to inject your code into the iframe.

Here is my approach...
http://jsfiddle.net/L2kEf/
html
<iframe src="http://www.bing.com"></iframe>
<div>I am div</div>
css
div { background: red; position: absolute; top: 20px; width: 100px; left:20px;}
iframe{width: 100%; height: 500px;}
you can add javascript/jquery too, so you could do something like,
jQuery //not 100% sure it would work coz of cross browser thingy, but you know, worth a try.
$('div').click(function (){
$('iframe').contents().html('changed');///
});
if this can't change any of the contents, you can display a dialog, to say it would normally work if it was in your website, then use #syserr0r approach for bookmarked users, for better results, since you are offering this kinda services, to developers, im sure they would know about bookmarking, my approach would be rarely used :) so hope it helps.

I had a problem of a similiar nature, and the main obstacle is the cross-domain policy.
You have to ask the user to put your code in a <script src="..."> or create a proxy solution that would add your code for them.
I went for the proxy and here are my observations:
it's easy to create a basic proxy in php - there are some php proxies on sourceforge and Ben Alman has created a simple php proxy for AJAX. Based on those I was able to create a php proxy altering the content properly in one day.
after that I spent a lot of time making it work with more and more sites with issues. You can never create a perfect proxy.
As an alternative (sa long as you are non-commercial) you can use http://www.jmarshall.com/tools/cgiproxy/ and put the site in an iframe and then do whatever you want to do with the iframes document, as it's in your domain thanks to the proxy. You can access iframeDOMnode.contentWindow.document then, etc.

You can create a Crossrider extension which your users can download.
Then simply add this to your App/Extension code:
appAPI.dom.addRemoteJS("http://yourdomain.com/file.js")
Your users can then download the extension (it works cross-browser for Internet Explorer, Chrome and Firefox) and it will load your JS code on every page load.

You can get an approximation of what it will look like using a iframe. Take a look at that link for an example.
http://jsfiddle.net/jzaun/5PjRy/
The issue with this appoch is that you can't move your DIV(s) when the page scrolls, they are in effect just floating over the iframe. There is no way around this as cross-domain scripting wont let you access the iframe's document to monitor scroll events.
The only other option you have for a better fitting example would be to load the page from the server side in whatever scripting language you are using and load that into the iframe (or into a div, etc.) and you can use javascript all you want as the page is coming from your domain.
For your example of what will your widget look like I imagine floating your DIV(s) over an iframe would give enough of an idea.
Please note the example you gave is using the server side method, not the iframe method.

I agree with the bookmarklet strategy.
I'm a fan of http://bookmarklets.heroku.com/, which lets you generate bookmarklets easily, inject jQuery, etc.