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How can I disable "Save Video As..." from a browser's right-click menu to prevent clients from downloading a video?
Are there more complete solutions that prevent the client from accessing a file path directly?
You can't.
That's because that's what browsers were designed to do: Serve content. But you can make it harder to download.
Convenient "Solution"
I'd just upload my video to a third-party video site, like YouTube or Vimeo. They have good video management tools, optimizes playback to the device, and they make efforts in preventing their videos from being ripped with zero effort on your end.
Workaround 1, Disabling "The Right Click"
You could disable the contextmenu event, aka "the right click". That would prevent your regular skiddie from blatantly ripping your video by right clicking and Save As. But then they could just disable JS and get around this or find the video source via the browser's debugger. Plus this is bad UX. There are lots of legitimate things in a context menu than just Save As.
Workaround 2, Video Player Libraries
Use custom video player libraries. Most of them implement video players that customize the context menu to your liking. So you don't get the default browser context menu. And if ever they do serve a menu item similar to Save As, you can disable it. But again, this is a JS workaround. Weaknesses are similar to Workaround 1.
Workaround 3, HTTP Live Streaming
Another way to do it is to serve the video using HTTP Live Streaming. What it essentially does is chop up the video into chunks and serve it one after the other. This is how most streaming sites serve video. So even if you manage to Save As, you only save a chunk, not the whole video. It would take a bit more effort to gather all the chunks and stitch them using some dedicated software.
Workaround 4, Painting on Canvas
Another technique is to paint <video> on <canvas>. In this technique, with a bit of JavaScript, what you see on the page is a <canvas> element rendering frames from a hidden <video>. And because it's a <canvas>, the context menu will use an <img>'s menu, not a <video>'s. You'll get a Save Image As instead of a Save Video As.
Workaround 5, CSRF Tokens
You could also use CSRF tokens to your advantage. You'd have your sever send down a token on the page. You then use that token to fetch your video. Your server checks to see if it's a valid token before it serves the video, or get an HTTP 401. The idea is that you can only ever get a video by having a token which you can only ever get if you came from the page, not directly visiting the video url.
This is a simple solution for those wishing to simply remove the right-click "save" option from the html5 videos
$(document).ready(function(){
$('#videoElementID').bind('contextmenu',function() { return false; });
});
Yes, you can do this in three steps:
Place the files you want to protect in a subdirectory of the directory where your code is running.
www.foo.com/player.html www.foo.com/videos/video.mp4
Save a file in that subdirectory named ".htaccess" and add the lines below.
www.foo.com/videos/.htaccess
#Contents of .htaccess
RewriteEngine on
RewriteCond %{HTTP_REFERER} !^http://foo.com/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.foo.com/.*$ [NC]
RewriteRule .(mp4|mp3|avi)$ - [F]
Now the source link is useless, but we still need to make sure any user attempting to download the file cannot be directly served the file.
For a more complete solution, now serve the video with a flash player (or html canvas) and never link to the video directly. To just remove the right click menu, add to your HTML:
<body oncontextmenu="return false;">
The Result:
www.foo.com/player.html will correctly play video, but if you visit www.foo.com/videos/video.mp4:
Error Code 403: FORBIDDEN
This will work for direct download, cURL, hotlinking, you name it.
This is a complete answer to the two questions asked and not an answer to the question: "can I stop a user from downloading a video they have already downloaded."
Simple answer,
YOU CAN'T
If they are watching your video, they have it already
You can slow them down but can't stop them.
The best way that I usually use is very simple, I fully disable context menu in the whole page, pure html+javascript:
<body oncontextmenu="return false;">
That's it! I do that because you can always see the source by right click.
Ok, you say: "I can use directly the browser view source" and it's true but we start from the fact that you CAN'T stop downloading html5 videos.
As a client-side developer I recommend to use blob URL,
blob URL is a client-side URL which refers to a binary object
<video id="id" width="320" height="240" type='video/mp4' controls > </video>
in HTML leave your video src blank,
and in JS fetch the video file using AJAX, make sure the response type is blob
window.onload = function() {
var xhr = new XMLHttpRequest();
xhr.open('GET', 'mov_bbb.mp4', true);
xhr.responseType = 'blob'; //important
xhr.onload = function(e) {
if (this.status == 200) {
console.log("loaded");
var blob = this.response;
var video = document.getElementById('id');
video.oncanplaythrough = function() {
console.log("Can play through video without stopping");
URL.revokeObjectURL(this.src);
};
video.src = URL.createObjectURL(blob);
video.load();
}
};
xhr.send();
}
Note: This method is not recommended for large file
EDIT
Use cross-origin blocking and header token checking to prevent direct downloading.
If the video is delivered via an API; Use a different http method (PUT / POST) instead of 'GET'
PHP sends the html5 video tag together with a session where the key is a random string and the value is the filename.
ini_set('session.use_cookies',1);
session_start();
$ogv=uniqid();
$_SESSION[$ogv]='myVideo.ogv';
$webm=uniqid();
$_SESSION[$webm]='myVideo.webm';
echo '<video autoplay="autoplay">'
.'<source src="video.php?video='.$ogv.' type="video/ogg">'
.'<source src="video.php?video='.$webm.' type="video/webm">'
.'</video>';
Now PHP is asked to send the video. PHP recovers the filename; deletes the session and sends the video instantly. Additionally all the 'no cache' and mime-type headers must be present.
ini_set('session.use_cookies',1);
session_start();
$file='myhiddenvideos/'.$_SESSION[$_GET['video']];
$_SESSION=array();
$params = session_get_cookie_params();
setcookie(session_name(),'', time()-42000,$params["path"],$params["domain"],
$params["secure"], $params["httponly"]);
if(!file_exists($file) or $file==='' or !is_readable($file)){
header('HTTP/1.1 404 File not found',true);
exit;
}
readfile($file);
exit:
Now if the user copy the url in a new tab or use the context menu he will have no luck.
We could make that not so easy by hiding context menu, like this:
<video oncontextmenu="return false;" controls>
<source src="https://yoursite.com/yourvideo.mp4" >
</video>
You can use
<video src="..." ... controlsList="nodownload">
https://developer.mozilla.org/en-US/docs/Web/API/HTMLMediaElement/controlsList
It doesn't prevent saving the video, but it does remove the download button and the "Save as" option in the context menu.
We ended up using AWS CloudFront with expiring URLs. The video will load, but by the time the user right clicks and chooses Save As the video url they initially received has expired. Do a search for CloudFront Origin Access Identity.
Producing the video url requires a key pair which can be created in the AWS CLI. FYI this is not my code but it works great!
$resource = 'http://cdn.yourwebsite.com/videos/yourvideourl.mp4';
$timeout = 4;
//This comes from key pair you generated for cloudfront
$keyPairId = "AKAJSDHFKASWERASDF";
$expires = time() + $timeout; //Time out in seconds
$json = '{"Statement":[{"Resource":"'.$resource.'","Condition" {"DateLessThan":{"AWS:EpochTime":'.$expires.'}}}]}';
//Read Cloudfront Private Key Pair
$fp=fopen("/absolute/path/to/your/cloudfront_privatekey.pem","r");
$priv_key=fread($fp,8192);
fclose($fp);
//Create the private key
$key = openssl_get_privatekey($priv_key);
if(!$key)
{
echo "<p>Failed to load private key!</p>";
return;
}
//Sign the policy with the private key
if(!openssl_sign($json, $signed_policy, $key, OPENSSL_ALGO_SHA1))
{
echo '<p>Failed to sign policy: '.openssl_error_string().'</p>';
return;
}
//Create url safe signed policy
$base64_signed_policy = base64_encode($signed_policy);
$signature = str_replace(array('+','=','/'), array('-','_','~'), $base64_signed_policy);
//Construct the URL
$url = $resource.'?Expires='.$expires.'&Signature='.$signature.'&Key-Pair-Id='.$keyPairId;
return '<div class="videowrapper" ><video autoplay controls style="width:100%!important;height:auto!important;"><source src="'.$url.'" type="video/mp4">Your browser does not support the video tag.</video></div>';
You can at least stop the the non-tech savvy people from using the right-click context menu to download your video. You can disable the context menu for any element using the oncontextmenu attribute.
oncontextmenu="return false;"
This works for the body element (whole page) or just a single video using it inside the video tag.
<video oncontextmenu="return false;" controls>...</video>
First of all realise it is impossible to completely prevent a video being downloaded, all you can do is make it more difficult. I.e. you hide the source of the video.
A web browser temporarily downloads the video in a buffer, so if could prevent download you would also be preventing the video being viewed as well.
You should also know that <1% of the total population of the world will be able to understand the source code making it rather safe anyway. That does not mean you should not hide it in the source as well - you should.
You should not disable right click, and even less you should display a message saying "You cannot save this video for copyright reasons. Sorry about that.". As suggested in this answer.
This can be very annoying and confusing for the user. Apart from that; if they disable JavaScript on their browser they will be able to right click and save anyway.
Here is a CSS trick you could use:
video {
pointer-events: none;
}
CSS cannot be turned off in browser, protecting your video without actually disabling right click. However one problem is that controls cannot be enabled either, in other words they must be set to false. If you are going to inplament your own Play/Pause function or use an API that has buttons separate to the video tag then this is a feasible option.
controls also has a download button so using it is not such a good idea either.
Here is a JSFiddle example.
If you are going to disable right click using JavaScript then also store the source of the video in JavaScript as well. That way if the user disables JavaScript (allowing right click) the video will not load (it also hides the video source a little better).
From TxRegex answer:
<video oncontextmenu="return false;" controls>
<source type="video/mp4" id="video">
</video>
Now add the video via JavaScript:
document.getElementById("video").src = "https://www.w3schools.com/html/mov_bbb.mp4";
Functional JSFiddle
Another way to prevent right click involves using the embed tag. This is does not however provide the controls to run the video so they would need to be inplamented in JavaScript:
<embed src="https://www.w3schools.com/html/mov_bbb.mp4"></embed>
well, you can't protect it 100% but you can make it harder. these methods that I'm explaining, I faced them during studying protection methods in PluralSight and BestDotNetTraining. nevertheless, none of these methods stopped me from downloading what I want, but I had a hard time to curate the downloader to pass their protection.
In addition to other mentioned methods to disable the context menu. the user still is able to use third-party tools like InternetDownload manager or other similar software to download the videos. the protection method that I'm explaining here is to mitigate those 3rd party software.
the requirement of all of these methods is to block a user when you identify someone is downloading your videos. in this way they are able to download only one or two videos only before you banned them from accessing to your website.
disclaimer
I will not accept any responsibility if someone abuses these methods or use it to harm others or the websites that I mentioned as an example. it's just for sharing knowledge to help you to protect your intellectual product.
generate links with an expiry
the requirement for this is to create a download link per user. that one can easily be handled by azure blob storage or amazon s3. you can create a download link with twice of the video length expiry timestamp. then you need to capture that video link and the time that is requested. this is necessary for the next method. the catch for this method is you are generating the download link when the user click the play button.
on play button event you will send a request to the server and get the link and update the source.
throttle the video request rate
then you monitor how fast the user request for the second video. if the user request for a download link too fast, then you block them right away. you can't put this threshold too big because you can mistakenly block users that are just browsing or skimming through the videos.
Enable HTTP Range
use some js library like videojs to play your video, also you need to return an AcceptRange in your header. Azure blob storage supports this out of the box. this way the browser starts to download the video chunk by chunk. usually, 32byte by 32byte. then you need to listen to videojs timeupdate change and update your server about the percentage that the video is watched. the percentage that the video is watched can't be more than the percentage that video is delivered. and if you are delivering a video content without receiving any percentage change, then you can block the user. because for sure they are downloading.
implementing this is tricky because the user can skip the video forward or backwards so be conscious about this when you are implementing this.
this is how BestDotnetTraining is handling the timeupdate
myPlayer.ready(function () {
//var player = this;
this.src({
type: "video/mp4",
src: videoURL
});
if (videoId) {
myPlayer.play();
this.on('timeupdate', function () {
var currentPercent = parseInt(100 * myPlayer.currentTime() / myPlayer.duration());//calcualte as percentage
if (currentPercent % 5 == 0) {
//send percentage to server
SaveVideoDurationWatched(currentPercent, videoId);
}
});
}
});
anyway, the user is able to work around this by using some download method that downloads a file through streaming. almost c# do it out of the box and for nodejs, you can use request module. then you need to start a stopWatch, listen to a package received and compare the total byte received compare to the total size. this way you can calculate a percentage and the time spent to get that amount of percentage. then use the Thread.Sleep() or something like that to delay the thread the amount that you have to wait if you watch the video normally. also before the sleep the user can call the server and update the percentage that is received. so the server thinks that the user is actually watching a video.
the calculation will be something like this, for example, if you calculate that you received 1 per cent so far, then you can calculate the amount that you should wait to sleep the download thread. in this way you can't download a video faster than what it's actual length is. if a video is 24 min. it will takes 24 min to download it. (plus the threshold we put in the first method)
original video length 24 minute
24 min *60000 = 1,440,000 miliseconds
1,440,000 % 100 = 14,400 milisecond is needed to download one percent
check the browser agent
when you are serving a webpage and serving the video link or accepting the progress update request you can look at the browser agent. if it's different then ban the user.
just be aware that some old browser doesn't pass this information. so you should ignore this when there is no browser agent in both video request and webpage request. but if one request has it and another one doesn't, then you should ban the user.
to work around this the user can set the browser agent header manually same as the headless browser that they are using to capture the download link.
check the referer header
when the referer is something other than your host URL or the page URL that you are serving the video, you can ban the user, because they put the download link in another tab or another application. even you can do that for the progress update request.
the requirement for this is to has a mapping of video and the page that shows that video. you can create some convention or pattern to understand what the URL should be, it's up to your design.
to work around it the user can set the referrer header manually equal to the download page URL when downloading the videos.
Calculate the time between request
if you receive so many requests that the time between them is the same, then you should block the user. you should put this to capture how much is time between the video link generation request. if they are the same (plus/minus some threshold) and it happens more than a number of times, then you can ban the user. because if there is a bot that is going to crawl your website or videos, then usually they have the same sleep time between their request. so if you receive each request, for example, every 1.3(plus/mins some deviation) minutes. then you raise an alarm. for this, you can use some statistic calculation to know the deviation between the requests.
to workaround this, the user can put a random sleep time between the requests.
sample code
I have a repo PluralSight-Downloader that is doing it halfway. I created this repo almost 5 years ago. because I wrote it for study purpose and own personal use only, the repo isn't received any update so far and I'm not going to update or make it easy to work with. it's just an example of how it can be done.
The
<body oncontextmenu="return false;">
no longer works. Chrome and Opera as of June 2018 has a submenu on the timeline to allow straight download, so user doesn't need to right click to download that video. Interestingly Firefox and Edge don't have this ...
Using a service such as Vimeo: Sign in Vimeo > Goto Video > Settings > Privacy > Mark as Secured, and also select embed domains. Once the embed domains are set, it will not allow anyone to embed the video or display it from the browser unless connecting from the domains specified. So, if you have a page that is secured on your server which loads the Vimeo player in iframe, this makes it pretty difficult to get around.
+1 simple and cross-browser way:
You can also put transparent picture over the video with css z-index and opacity.
So users will see "save picture as" instead of "save video" in context menu.
Here's what I did:
function noRightClick() {
alert("You cannot save this video for copyright reasons. Sorry about that.");
}
<body oncontextmenu="noRightClick();">
<video>
<source src="http://calumchilds.com/videos/big_buck_bunny.mp4" type="video/mp4">
</video>
</body>
This also works for images, text and pretty much anything. However, you can still access the "Inspect" and the "View source" tool through keyboard shortcuts. (As the answer at the top says, you can't stop it entirely.) But you can try to put barriers up to stop them.
Here's a complete solution for disabling download including right click > Save as... in the context menu:
<video oncontextmenu="return false;" controlsList="nodownload">
</video>
Short Answer: Encrypt the link like youtube does, don't know how than ask youtube/google of how they do it. (Just in case you want to get straight into the point.)
I would like to point out to anyone that this is possible because youtube does it and if they can so can any other website and it isn't from the browser either because I tested it on a couple browsers such as microsoft edge and internet explorer and so there is a way to disable it and seen that people still say it...I tries looking for an answer because if youtube can than there has to be a way and the only way to see how they do it is if someone looked into the scripts of youtube which I am doing now. I also checked to see if it was a custom context menu as well and it isn't because the context menu is over flowing the inspect element and I mean like it is over it and I looked and it never creates a new class and also it is impossible to actually access inspect element with javascript so it can't be. You can tell when it double right-click a youtube video that it pops up the context menu for chrome. Besides...youtube wouldn't add that function in. I am doing research and looking through the source of youtube so I will be back if I find the answer...if anyone says you can't than, well they didn't do research like I have. The only way to download youtube videos is through a video download.
Okay...I did research and my research stays that you can disable it except there is no javascript to it...you have to be able to encrypt the links to the video for you to be able to disable it because I think any browser won't show it if it can't find it and when I opened a youtube video link it showed as this "blob:https://www.youtube.com/e5c4808e-297e-451f-80da-3e838caa1275" without quotes so it is encrypting it so it cannot be saved...you need to know php for that but like the answer you picked out of making it harder, youtube makes it the hardest of heavy encrypting it, you need to be an advance php programmer but if you don't know that than take the person you picked as best answer of making it hard to download it...but if you know php than heavy encrypt the video link so it only is able to be read on yours...I don't know how to explain how they do it but they did and there is a way. The way youtube Encrypts there videos is quite smart so if you want to know how to than just ask youtube/google of how they do it...hope this helps for you although you already picked a best answer. So encrypting the link is best in short terms.
controlsList Prevent action such as download begin fullscreen without adding any other JavaScript function
<video width="400" controlsList="nofullscreen nodownload" controls>
Try this for disable download Video options
<video src="" controls controlsList="nodownload"></video>
It seems like streaming the video through websocket is a viable option, as in stream the frames and draw them on a canvas sort of thing.
Video streaming over websockets using JavaScript
I think that would provide another level of protection making it more difficult for the client to acquire the video and of course solve your problem with "Save video as..." right-click context menu option ( overkill ?! ).
If you are looking for a complete solution/plugin, I've found this very useful
https://github.com/mediaelement/mediaelement
Prevent HTML5 video from being downloaded (right-click saved)
<video type="video/mp4" width="330" height="300" controlsList="nodownload" oncontextmenu="return false;" controls></video>
You can't.
For example, people can use some APIfor example desktopCapture, getUserMedia that
allows users to record screen, window, tab.
People can use it and write it to the canvas and then concatenate all the chunks together to get the video,
So there is no way to stop them from downloading the video if they really want it.
I found a good answer to a similar problem, using PHP instead of JavaScript for better security.
I want to play test.mp4 in the user's browser using the browser's default player (just as though URL/test.mp4 had been clicked on a Web page), but requiring a password, which is either supplied by the user or internally by software.
Here is a brief sketch of the idea. It starts with the user going to (running) a program I wrote called secure.php to play test.mp4.
The file test.mp4 is in a subdirectory ("secureSubdirectory") that contains a .htaccess containing "Require all denied". This immediately prevents any direct access through a URL.
When secure.php is run, it supplies a password (or queries the user for a password), then does a POST to itself that includes the password, verifies it using a salt, using the PHP commands:
$Hash=base64_encode(hash_hmac("sha256",$Pwd,$Salt,true));
$HashesAreSame=hash_equals($Hash,$GoalHash);
then tests for test.mp4 existing, and executes the following PHP code to return the test.mp4 file as a byte stream to the user's browser:
header("Content-Type: video/mp4");
echo file_get_contents("secureSubdirectory/$path");
exit;
The video shows as expected. If I then right-click on the page showing the video and try saving the video, the resulting file will just contain an error string, like "Error: password not found", since test.mp4 is being queried using the plain secure.php URL, not through POST with the correct password.
Of course, you can obtain the response payload (the video bytes) using the Network option of the browser debugging tools, but this could be prevented by the PHP program or the .htaccess file if the browser provided an option to prevent access to the debugging tools.
I can't imagine a failure case, but I'd be very interested if one exists, as simple but perfect authorization is a very rare thing. (Note that, since this method relies on a password, associating it with the user is not a secure way to authenticate, since the user can accidentally or deliberately publish or share the password.)
#Clayton-Graul had what I was looking for, except I needed the CoffeeScript version for a site using AngularJS. Just in case you need that too, here's what you put in the AngularJS controller in question:
# This is how to we do JQuery ready() dom stuff
$ ->
# let's hide those annoying download video options.
# of course anyone who knows how can still download
# the video, but hey... more power to 'em.
$('#my-video').bind 'contextmenu', ->
false
"strange things are afoot at the circle k" (it's true)
Everything you see in the browser is downloaded content. The question being alluded to is how to save that content in the browser. To view content, client browsers download from content servers and make it available locally.
One solution becoming popular is to save (ephemeral) content in browser only, and for a limited time, in a way that cannot be saved directly. Blobs are one implementation of this with the added benefit of reducing bandwidth & storage overheads, since the content is stored in binary objects.
The short expiry of content makes persistent storage almost impossible to ordinary users since new content is displayed before user can attempt to save expired content.
I have the following config flags in my com.omniture.AppMeasurement setup (swc version FAS-3.4.7)
trackingServer: "metrics.my-site.com",
trackingServerSecure: "smetrics.my-site.com"
and when visiting https://my-site.com and I'm seeing beacons go to metrics.my-site.com instead of smetrics.mysite.com. The page tracking is reporting to the secure page, but the swf based video metrics are not. The html5 fallback is also behaving correctly, it's only the swf that has this problem. (The swf is also being loaded via https)
What determines where the beacons are going and if it's just the parent url, what else could cause this to default to the http beacon url?
Looks like this might work:
actionSource = new ActionSource();
actionSource.ssl = true;
I would like to know if there is an alternative to iFrames with HTML5.
I mean by that, be able to inject cross-domains HTML inside of a webpage without using an iFrame.
Basically there are 4 ways to embed HTML into a web page:
<iframe> An iframe's content lives entirely in a separate context than your page. While that's mostly a great feature and it's the most compatible among browser versions, it creates additional challenges (shrink wrapping the size of the frame to its content is tough, insanely frustrating to script into/out of, nearly impossible to style).
AJAX. As the solutions shown here prove, you can use the XMLHttpRequest object to retrieve data and inject it to your page. It is not ideal because it depends on scripting techniques, thus making the execution slower and more complex, among other drawbacks.
Hacks. Few mentioned in this question and not very reliable.
HTML5 Web Components. HTML Imports, part of the Web Components, allows to bundle HTML documents in other HTML documents. That includes HTML, CSS, JavaScript or anything else an .html file can contain. This makes it a great solution with many interesting use cases: split an app into bundled components that you can distribute as building blocks, better manage dependencies to avoid redundancy, code organization, etc. Here is a trivial example:
<!-- Resources on other origins must be CORS-enabled. -->
<link rel="import" href="http://example.com/elements.html">
Native compatibility is still an issue, but you can use a polyfill to make it work in evergreen browsers Today.
You can learn more here and here.
You can use object and embed, like so:
<object data="http://www.web-source.net" width="600" height="400">
<embed src="http://www.web-source.net" width="600" height="400"> </embed>
Error: Embedded data could not be displayed.
</object>
Which isn't new, but still works. I'm not sure if it has the same functionality though.
object is an easy alternative in HTML5:
<object data="https://github.com/AbrarJahin/Asp.NetCore_3.1-PostGRE_Role-Claim_Management/"
width="400"
height="300"
type="text/html">
Alternative Content
</object>
You can also try embed:
<embed src="https://github.com/AbrarJahin/Asp.NetCore_3.1-PostGRE_Role-Claim_Management/"
width=200
height=200
onerror="alert('URL invalid !!');" />
Re-
As currently, StackOverflow has turned off support for showing external URL contents, run code snippet is not showing anything. But for your site, it will work perfectly.
No, there isn't an equivalent. The <iframe> element is still valid in HTML5. Depending on what exact interaction you need there might be different APIs. For example there's the postMessage method which allows you to achieve cross domain javascript interaction. But if you want to display cross domain HTML contents (styled with CSS and made interactive with javascript) iframe stays as a good way to do.
If you want to do this and control the server from which the base page or content is being served, you can use Cross Origin Resource Sharing (http://www.w3.org/TR/access-control/) to allow client-side JavaScript to load data into a <div> via XMLHttpRequest():
// I safely ignore IE 6 and 5 (!) users
// because I do not wish to proliferate
// broken software that will hurt other
// users of the internet, which is what
// you're doing when you write anything
// for old version of IE (5/6)
xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if(xhr.readyState == 4 && xhr.status == 200) {
document.getElementById('displayDiv').innerHTML = xhr.responseText;
}
};
xhr.open('GET', 'http://api.google.com/thing?request=data', true);
xhr.send();
Now for the lynchpin of this whole operation, you need to write code for your server that will give clients the Access-Control-Allow-Origin header, specifying which domains you want the client-side code to be able to access via XMLHttpRequest(). The following is an example of PHP code you can include at the top of your page in order to send these headers to clients:
<?php
header('Access-Control-Allow-Origin: http://api.google.com');
header('Access-Control-Allow-Origin: http://some.example.com');
?>
This also does seem to work, although W3C specifies it is not intended "for an external (typically non-HTML) application or interactive content"
<embed src="http://www.somesite.com" width=200 height=200 />
More info:
http://www.w3.org/wiki/HTML/Elements/embed
http://www.w3schools.com/tags/tag_embed.asp
An iframe is still the best way to download cross-domain visual content. With AJAX you can certainly download the HTML from a web page and stick it in a div (as others have mentioned) however the bigger problem is security. With iframes you'll be able to load the cross domain content but won't be able to manipulate it since the content doesn't actually belong to you. On the other hand with AJAX you can certainly manipulate any content you are able to download but the other domain's server needs to be setup in such a way that will allow you to download it to begin with. A lot of times you won't have access to the other domain's configuration and even if you do, unless you do that kind of configuration all the time, it can be a headache. In which case the iframe can be the MUCH easier alternative.
As others have mentioned you can also use the embed tag and the object tag but that's not necessarily more advanced or newer than the iframe.
HTML5 has gone more in the direction of adopting web APIs to get information from cross domains. Usually web APIs just return data though and not HTML.
I created a node module to solve this problem node-iframe-replacement. You provide the source URL of the parent site and CSS selector to inject your content into and it merges the two together.
Changes to the parent site are picked up every 5 minutes.
var iframeReplacement = require('node-iframe-replacement');
// add iframe replacement to express as middleware (adds res.merge method)
app.use(iframeReplacement);
// create a regular express route
app.get('/', function(req, res){
// respond to this request with our fake-news content embedded within the BBC News home page
res.merge('fake-news', {
// external url to fetch
sourceUrl: 'http://www.bbc.co.uk/news',
// css selector to inject our content into
sourcePlaceholder: 'div[data-entityid="container-top-stories#1"]',
// pass a function here to intercept the source html prior to merging
transform: null
});
});
The source contains a working example of injecting content into the BBC News home page.
You can use an XMLHttpRequest to load a page into a div (or any other element of your page really). An exemple function would be:
function loadPage(){
if (window.XMLHttpRequest){
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}else{
// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function(){
if (xmlhttp.readyState==4 && xmlhttp.status==200){
document.getElementById("ID OF ELEMENT YOU WANT TO LOAD PAGE IN").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("POST","WEBPAGE YOU WANT TO LOAD",true);
xmlhttp.send();
}
If your sever is capable, you could also use PHP to do this, but since you're asking for an HTML5 method, this should be all you need.
The key issue to load another site's page in your own site's page is security. There is cross-site security policy defined, you would have no chance to load it directly in your iframe if another site has it set to strict same origin policy. Hence to find an alternative to iframe, they must be able to bypass this security policy restriction, even in the future, if any new component is introduced by WSC, it would have similar security restrictions.
For now, the best way to bypass this is to simulate a normal page access in your logic, this means AJAX + server side access maybe a good option. You can set up some proxy at your server side and fetch the page content and load it into the iframe. This works but not perfect as if there is any link or image in the content and they may not be accessible.
Normally if you try to load a page in your own iframe, you would need to check whether the page can be loaded in iframe or not. This post gives some guidelines on how to do the check.
You should have a look into JSON-P - that was a perfect solution for me when I had that problem:
https://en.wikipedia.org/wiki/JSONP
You basically define a javascript file that loads all your data and another javascript file that processes and displays it. That gets rid of the ugly scrollbar of iframes.
I have a problem where users are reporting that their images aren't being uploaded and the old ones are still there. On closer inspection the new images are there, they just have the same name as the old one. What I do on the upload is that I rename the images for SEO purposes. When they delete an image the old index becomes available and is reused. Therefore it has the same image name.
Is there a way to (i thought maybe there might be a meta tag for this) to tell the browser to not use its cahce?
The better answer is to rename the image to something totally new. I will get working on that but in the mean time is the quick solution while I work on the bigger problem.
Append a query string with an arbitrary unique number (or time, or version number, etc.):
<img src="image.png?80172489074" alt="a cool image" />
This will result in a new request, because of the different URL.
It's tough. You really want images to be cached, but then you don't want to cache them once a new ones available:
Using expires header with a date in the past prevents any caching. Bad
Adding a "cache busting" parameter ?342038402 can fix the problem, but can also prevent the image ever from being cached, which is not what you want. Bad.
Using expires header with a short (lets say 1 hr) expires is better... after an hour the user will see the image, but your web server won't have to serve it every time. Compromise, but what time works? Not really feasible.
The solution? I can think of two good options:
Look into eTags, and your ability to use them. These are designed for this situation. The browser will explicitly ask your server whether the file is up-to-date or not. You can just turn this on in apache if you don't have it aleady.
Create a new URL for each new image (and use a far-future expires header). This is what you are working on.
My favourite PHP solution:
<img src="<?php echo "image.jpg" . "?v=" . filemtime("image.jpg"); ?>" />
every change of file "create" a new version of the file
Append the current datetime to the image src:
<img src="yourImage.png?v=<?php echo Date("Y.m.d.G.i.s")?>" />
You can put http-equiv in <meta> tag which will tell browser not to use cache (or even better -- use it in some defined way), but it is better to configure server to send proper http cache headers. Check out article on caching.
Still, some browsers might not support all of http standard, but I believe it's the way to go.
Another powerfull solution:
<img src="image.png?v=<?php echo filemtime("image.png"); ?>" />
This print the "last-modification-timestamp" on the path.
New version --> Download new image
Same version --> Take cache's one
Go Random. Just use some random number and append it with image filename.
<img src="image.jpg?<?=rand(1,1000000)?>">
you can control the cache behaviour by playing with the HTTP headers.
setting the expires header in past would force browser to not use cached version.
Expires: Sat, 26 Jul 1997 05:00:00 GMT
You can consult the RFC to have more details.
If you look at the data that is exchanged between your browser and the server, you'll see that the browser will send a HTTP HEAD request for the images. The result will contain the modification time (but not the actual image data). Make sure that this time changes if the image changes on the server and the browser should download the image again.
in PHP you can use this trick
<img src="image.png?<?php echo time(); ?>" />
The time() function show the current timestamp. Every page load is different. So this code deceive the browser: it read another path and it "think" that the image is changed since the user has visited the site the last time. And it has to re-download it, instead of use the cache one.
It sounds like the concern is more about the primary user seeing their new image than cache being disabled entirely? If that's the case, you can do the following:
var headers = new Headers()
headers.append('pragma', 'no-cache')
headers.append('cache-control', 'no-cache')
var init = {
method: 'GET',
headers: headers,
mode: 'no-cors',
cache: 'no-cache',
}
fetch(new Request('path/to.file'), init)
If you do this after a new image is uploaded, the browser should see those headers and make a call to the backend, skipping the cache. The new image is now in cache under that URL. The primary user will see the new image, but you still retain all the benefits of caching. Anyone else viewing this image will see updates in a day or so once their cache invalidates.
If the concern was more about making sure all users see the most up to date version, you would want to use one of the other solutions.
In PHP you can send a random number or the current timestamp:
<img src="image.jpg?<?=Date('U')?>">
or
<img src="image.jpg?<?=rand(1,32000)?>">
that was not ok result, I think this is the way to program it correct.
<td><?php echo "<img heigth=90 width=260 border=1 vspace=2 hspace=2 src=".$row['address']."?=".rand(1,999)."/>" ?></td>
I had come up with this issue some times ago. And I was getting data through JSON in AJAX.
So what I did is, I just added a Math.random() Javascript function and It worked like a charm.
The backend I used was a flask.
<img class="card-img-top w-100 d-block" style="padding:30px;height:400px" src="static/img/${data.image}?${Math.random()} ">
I generate some images using a PHP lib.
Sometimes the browser does not load the new generated file.
How can I disable cache just for images created dynamically by me?
Note: I have to use same name for the created images over time.
A common and simple solution to this problem that feels like a hack but is fairly portable is to add a randomly generated query string to each request for the dynamic image.
So, for example -
<img src="image.png" />
Would become
<img src="image.png?dummy=8484744" />
Or
<img src="image.png?dummy=371662" />
From the point of view of the web-server the same file is accessed, but from the point of view of the browser no caching can be performed.
The random number generation can happen either on the server when serving the page (just make sure the page itself isn't cached...), or on the client (using JavaScript).
You will need to verify whether your web-server can cope with this trick.
Browser caching strategies can be controlled by HTTP headers. Remember that they are just a hint, really. Since browsers are terribly inconsistent in this (and any other) field, you'll need several headers to get the desired effect on a range of browsers.
header ("Pragma-directive: no-cache");
header ("Cache-directive: no-cache");
header ("Cache-control: no-cache");
header ("Pragma: no-cache");
header ("Expires: 0");
Solution 1 is not great. It does work, but adding hacky random or timestamped query strings to the end of your image files will make the browser re-download and cache every version of every image, every time a page is loaded, regardless of whether or not the image has changed on the server.
Solution 2 is useless. Adding nocache headers to an image file is not only very difficult to implement, but it's completely impractical because it requires you to predict when it will be needed in advance, the first time you load any image that you think might change at some point in the future.
Enter Etags...
The absolute best way I've found to solve this is to use ETAGS inside a .htaccess file in your images directory. The following tells Apache to send a unique hash to the browser in the image file headers. This hash only ever changes when the image file is modified and this change triggers the browser to reload the image the next time it is requested.
<FilesMatch "\.(jpg|jpeg)$">
FileETag MTime Size
</FilesMatch>
If you need to do it dynamically in the browser using javascript, here is an example...
<img id=graph alt=""
src="http://www.kitco.com/images/live/gold.gif"
/>
<script language="javascript" type="text/javascript">
var d = new Date();
document.getElementById("graph").src =
"http://www.kitco.com/images/live/gold.gif?ver=" +
d.getTime();
</script>
I checked all the answers and the best one seemed to be (which isn't):
<img src="image.png?cache=none">
at first.
However, if you add cache=none parameter (which is static "none" word), it doesn't effect anything, browser still loads from cache.
Solution to this problem was:
<img src="image.png?nocache=<?php echo time(); ?>">
where you basically add unix timestamp to make the parameter dynamic and no cache, it worked.
However, my problem was a little different:
I was loading on the fly generated php chart image, and controlling the page with $_GET parameters. I wanted the image to be read from cache when the URL GET parameter stays the same, and do not cache when the GET parameters change.
To solve this problem, I needed to hash $_GET but since it is array here is the solution:
$chart_hash = md5(implode('-', $_GET));
echo "<img src='/images/mychart.png?hash=$chart_hash'>";
Edit:
Although the above solution works just fine, sometimes you want to serve the cached version UNTIL the file is changed. (with the above solution, it disables the cache for that image completely)
So, to serve cached image from browser UNTIL there is a change in the image file use:
echo "<img src='/images/mychart.png?hash=" . filemtime('mychart.png') . "'>";
filemtime() gets file modification time.
I know this topic is old, but it ranks very well in Google. I found out that putting this in your header works well;
<meta Http-Equiv="Cache-Control" Content="no-cache">
<meta Http-Equiv="Pragma" Content="no-cache">
<meta Http-Equiv="Expires" Content="0">
<meta Http-Equiv="Pragma-directive: no-cache">
<meta Http-Equiv="Cache-directive: no-cache">
I was just looking for a solution to this, and the answers above didn't work in my case (and I have insufficient reputation to comment on them). It turns out that, at least for my use-case and the browser I was using (Chrome on OSX), the only thing that seemed to prevent caching was:
Cache-Control = 'no-store'
For completeness i'm now using all 3 of 'no-cache, no-store, must-revalidate'
So in my case (serving dynamically generated images out of Flask in Python), I had to do the following to hopefully work in as many browsers as possible...
def make_uncached_response(inFile):
response = make_response(inFile)
response.headers['Pragma-Directive'] = 'no-cache'
response.headers['Cache-Directive'] = 'no-cache'
response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
response.headers['Pragma'] = 'no-cache'
response.headers['Expires'] = '0'
return response
Changing the image source is the solution. You can indeed do this by adding a timestamp or random number to the image.
Better would be to add a checksum of eg the data the image represents. This enables caching when possible.
Let's add another solution one to the bunch.
Adding a unique string at the end is a perfect solution.
example.jpg?646413154
Following solution extends this method and provides both the caching capability and fetch a new version when the image is updated.
When the image is updated, the filemtime will be changed.
<?php
$filename = "path/to/images/example.jpg";
$filemtime = filemtime($filename);
?>
Now output the image:
<img src="images/example.jpg?<?php echo $filemtime; ?>" >
i had this problem and overcoming like this.
var newtags='<div class="addedimage"><h5>preview image</h5><img src="'+one+'?nocache='+Math.floor(Math.random() * 1000)+'"></div>';
I've used this to solve my similar problem ... displaying an image counter (from an external provider). It did not refresh always correctly. And after a random parameter was added, all works fine :)
I've appended a date string to ensure refresh at least every minute.
sample code (PHP):
$output .= "<img src=\"http://xy.somecounter.com/?id=1234567890&".date(ymdHi)."\" alt=\"somecounter.com\" style=\"border:none;\">";
That results in a src link like:
http://xy.somecounter.com/?id=1234567890&1207241014
If you have a hardcoded image URL, for example: http://example.com/image.jpg you can use php to add headers to your image.
First you will have to make apache process your jpg as php.
See here:
Is it possible to execute PHP with extension file.php.jpg?
Load the image (imagecreatefromjpeg) from file then add the headers from previous answers. Use php function header to add the headers.
Then output the image with the imagejpeg function.
Please notice that it's very insecure to let php process jpg images. Also please be aware I haven't tested this solution so it is up to you to make it work.
Simple, send one header location.
My site, contains one image, and after upload the image, there not change, then I add this code:
<?php header("Location: pagelocalimage.php"); ?>
Work's for me.