Prevent user from saving video files - javascript

I am currently building an application with ReactJs and MongoDB displaying videos. My problem is that I want to prevent the end user from saving those videos either by accessing the console and inspect it and therefore get the url of the video or by simply downloading it on their computer.
At the moment, I have a script that disconnects the user if he opens the devTools :
useEffect(() => {
console.log(Object.defineProperties(new Error, {
message: {get() {
setOpened(true)
}
},
toString: {value() {(new Error).stack.includes('toString#')&&alert('Safari')}}
}));
if (openned) {
logoutHandler()
}
}, []);
And other one to prevent right clicking :
useEffect(() => {
document.onkeydown = function (e) {
return false;
};
document.addEventListener('contextmenu', (e) => {
e.preventDefault();
setOpened(true)
});
}, []);
The problem is that with a simple add-on, https://addons.mozilla.org/fr/firefox/addon/absolute-enable-right-click/, the user can right click again and save the video by clicking on "Save video as...".
I have also thought of splitting the videos when I upload them and then kind of "stream" them, but I haven't found any proper documentation on the subject...
Currently the videos are stored into a Firebase bucket.
Would you have any advice on the matter please ?

IMO The best you can do is make it difficult and it sounds like you are doing a very good job of it. (minify your code to help prevent users from using local orverrides to get past your security, you can also look into DRM)
However you cannot 100% prevent a user from saving the video if they are left alone with the source.
The user can just setup a camera, screen record, packet sniff (wireshark), modify your javascript (local overrides), etc etc.
firewalls don't stop dragons and all that.
I believe the only way to do what you are trying to do is to monitor the users while they watch the videos.
If your users need accounts to view the videos, then flashing a few pixels at special spots to be decoded later as the users id is one way to track down who is leaking your videos and remove them, but even that has its issues (compression, cropping, watermarks etc).

Related

Asynchronous javascript in a synchronous function when combining mediaStreams from getUserMedia and getDisplayMedia?

My team is adapting the sipml5 library to create a html5 softphone for use in our organization. The full repository is here: https://github.com/L1kMakes/sipml5-ng . We have the code working well; audio and video calls work flawlessly. In the original code we forked from (which was from like 2012) screen sharing was accomplished with a browser plugin, but HTML 5 and WebRTC have changed to allow this to be done with just JavaScript now.
I am having difficulty adapting the code to accommodate this. I am starting with the code here on line 828: https://github.com/L1kMakes/sipml5-ng/blob/master/src/tinyMEDIA/src/tmedia_session_jsep.js This works, though without audio. That makes sense as the only possible audio stream from a screen share is the screen audio, not the mic audio. I am attempting to initialize an audio stream from getUserMedia, grab a video stream from getDisplayMedia, and present that to the client as a single mediaStream. Here's my adapted code:
if ( this.e_type == tmedia_type_e.SCREEN_SHARE ) {
// Plugin-less screen share using WebRTC requires "getDisplayMedia" instead of "getUserMedia"
// Because of this, audio constraints become limited, and we have to use async to deal with
// the promise variable for the mediastream. This is a change since Chrome 71. We are able
// to use the .then aspect of the promise to call a second mediaStream, then attach the audio
// from that to the video of our second screenshare mediaStream, enabling plugin-less screen
// sharing with audio.
let o_stream = null;
let o_streamAudio = null;
let o_streamVideo = null;
let o_streamAudioTrack = null;
let o_streamVideoTrack = null;
try {
navigator.mediaDevices.getDisplayMedia(
{
audio: false,
video: !!( this.e_type.i_id & tmedia_type_e.VIDEO.i_id ) ? o_video_constraints : false
}
).then(o_streamVideo => {
o_streamVideoTrack = o_streamVideo.getVideoTracks()[0];
navigator.mediaDevices.getUserMedia(
{
audio: o_audio_constraints,
video: false
}
).then(o_streamAudio => {
o_streamAudioTrack = o_streamAudio.getAudioTracks()[0];
o_stream = new MediaStream( [ o_streamVideoTrack , o_streamAudioTrack ] );
tmedia_session_jsep01.onGetUserMediaSuccess(o_stream, This);
});
});
} catch ( s_error ) {
tmedia_session_jsep01.onGetUserMediaError(s_error, This);
}
} else {
try {
navigator.mediaDevices.getUserMedia(
{
audio: (this.e_type == tmedia_type_e.SCREEN_SHARE) ? false : !!(this.e_type.i_id & tmedia_type_e.AUDIO.i_id) ? o_audio_constraints : false,
video: !!(this.e_type.i_id & tmedia_type_e.VIDEO.i_id) ? o_video_constraints : false // "SCREEN_SHARE" contains "VIDEO" flag -> (VIDEO & SCREEN_SHARE) = VIDEO
}
).then(o_stream => {
tmedia_session_jsep01.onGetUserMediaSuccess(o_stream, This);
});
} catch (s_error ) {
tmedia_session_jsep01.onGetUserMediaError(s_error, This);
}
}
My understanding is, o_stream should represent the resolved mediaStream tracks, not a promise, when doing a screen share. On the other end, we are using the client "MicroSIP." When making a video call, when the call is placed, I get my video preview locally in our web app, then when the call is answered the MicroSIP client gets a green square for a second, then resolves to my video. When I make a screen share call, my local web app sees the local preview of the screen share, but upon answering the call, my MicroSIP client just gets a green square and never gets the actual screen share.
The video constraints for both are the same. If I add debugging output to get more descriptive of what is actually in the media streams, they appear identical as far as I can tell. I made a test video call and a test screen share call, captured debug logs from each and held them side by side in notepad++...all appears to be identical save for the explicit debug describing the traversal down the permission request tree with "GetUserMedia" and "GetDisplayMedia." I can't really post the debug logs here as cleaning them up of information from my organization would leave them pretty barren. Save for the extra debug output on the "getDisplayMedia" call before "getUserMedia", timestamps, and uniqueID's related to individual calls, the log files are identical.
I am wondering if the media streams are not resolving from their promises before the "then" is completed, but asynchronous javascript and promises is still a bit over my head. I do not believe I should convert this function to async, but I have nothing else to debug here; the mediaStream is working as I can see it locally, but I'm stumped on figuring out what is going on with the remote send.
The solution was...nothing, the code was fine. It turns out the recipient SIP client we were using had an issue where it just aborts if it gets video larger than 640x480.

Download Video from URL without opening in chrome browser

I have registered for a course that has roughly 150 videos.
What I have done Uptil NOW:
There is no download button available right now.
In order to get the URL of each video file, I have created the script which I run through Console as below:
The site where I am watching these videos is different than the xxxxx marked site.
e.g. I am watching on linkedin learning and video is on lynda,etc.
console.log(("<h2>"+ document.title)+"</h2>"
+
" click here ");
document.getElementsByClassName("video-next-button")[0].click();
an example of output from above code is:
<h2>Overview of QGIS features: Learning QGIS (2015)</h2>
<a href="https://files3.xxxxx.com/secure/courses/383524/VBR_MP4h264_main_SD/383524_01_01_XR15_Overview.mp4?V0lIWk4afWPs3ejN5lxsCi1SIkGKYcNR_F7ijKuQhDmS1sYUK7Ps5TYBcV-MHzdVTujT5p03HP10F_kqzhwhqi38fhOAPnNJz-dMyvA2-YIpBOI-wGtuOjItlVbRUDn6QUWpwe1sRoAl__IA1zmJn3gPvC7Fu926GViqVdLa3oLB0mxRGa7i> click here </a>
I have replaced domain name with xxxxx
This way I can get cover all videos without clicking next (I would like to know if I can automate this process by using some timeout techniques as well)
each of this link, when clicked, chrome window looks like below:
this way after clicking 3dots -> Download, I can save video individually.
What I want:
Method to save all videos without the need to open individually.
Challenge
To begin with, fetching and saving large binary files is possible when:
The host server's CORS support is enabled.
Accessing the host's network from the same site-origin.
Server-to-Server.
Okay, this would reason why your anchor attempt did not work, in fact, accessing the host's network from your localhost will deny you from accessing the resource's content unless the host server's CORS support is enabled which is unlikely.
Workaround
Alternatively, this will leave us with the other two options, accessing from the same site-origin in particular due to its simplicity, the strategy lies in executing the fetching/saving script from the browser itself, thus, the host server will be gentle with the requests, since they are very similar to the ones coming from the same site.
Steps
Go to the site you wish to download the files from (I used https://www.sample-videos.com).
Right-click the web page and select 'Inspect' (Ctrl + Shift + I).
Finally, switch to the 'Console' tab to start coding.
Code
const downloadVideos = (videos, marker) => {
// it's important to throttle between requests to dodge performance or network issues
const throttleTime = 10000; // in milliseconds; adjust it to suit your hardware/network capabilities
const domain = 'https://www.sample-videos.com'; // site's domain
if (marker < videos.length) {
console.log(`Download initiated for video ${videos[marker].name} # marker:${marker}`);
const anchorElement = document.createElement('a');
anchorElement.setAttribute('href', `${domain}${videos[marker].src}`);
anchorElement.setAttribute('download', videos[marker].name);
document.body.appendChild(anchorElement);
// trigger download manually
anchorElement.click();
anchorElement.remove();
marker += 1;
setTimeout(downloadVideos, throttleTime, videos, marker);
}
};
// assuming all videos are stored in an array, each video must have 'src' and 'name' attributes
const videos = [
{ src: '/video123/mp4/480/big_buck_bunny_480p_30mb.mp4', name: 'video_480p.mp4' },
{ src: '/video123/mp4/720/big_buck_bunny_720p_1mb.mp4', name: 'video_720p.mp4' }
];
// fireup
downloadVideos(videos, 0);
... ahem!

Record browser tab with javascript

Is it possible to record the current tab of the browser using just javascript and nothing else? I don't want to use chrome or firefox extension.
What I want to do is that the presenter would like to record his current tab and share it with others.
If it's possible what is the best way to do this?
There is... something that is in the process of being defined: MediaCapture Screen Share API.
This will allow to create a MediaStream from different sources such as the user's screen, or one of their apps' window, or some unclear-to-me "browser" thing.
From this MediaStream, it is easy to record it with the MediaRecorder API.
Currently, no browser has really implemented what is being defined there, but you can get some experimental implementations in Firefox, and, only from extension in Chrome.
This API doesn't really define a way to choose the current tab by default though, so your users will have to select this tab themselves from a prompt.
Live Example that will currently work only in Firefox.
And mandatory code block to be able to link to the fiddle, even though this code will not work anywhere for now!
navigator.getDisplayMedia({ video: true })
.then(stream => {
// we have a stream, we can record it
const chunks = [];
const recorder = new MediaRecorder(stream);
recorder.ondataavailable = e => chunks.push(e.data);
recorder.onstop = e => exportVid(new Blob(chunks));
recorder.start();
// defineWhenWeStopRecorder(recorder)
}, error => {
console.log("Unable to acquire screen capture", error);
});
I have not worked on recorder yet.
But found this post that may help. It is an API.
https://hacks.mozilla.org/2016/04/record-almost-everything-in-the-browser-with-mediarecorder/

iframe content doesn't always load

So I have a system that essentially enabled communication between two computers, and uses a WebRTC framework to achieve this:
"The Host": This is the control computer, and clients connect to this. They control the clients window.
"The Client": The is the user on the other end. They are having their window controlled by the server.
What I mean by control, is that the host can:
change CSS on the clients open window.
control the URL of an iframe on the clients open window
There are variations on these but essentially thats the amount of control there is.
When "the client" logs in, the host sends a web address to the client. This web address will then be displayed in an iframe, as such:
$('#iframe_id').attr("src", URL);
there is also the ability to send a new web address to the client, in the form of a message. The same code is used above in order to navigate to that URL.
The problem I am having is that on, roughly 1 in 4 computers the iframe doesn't actually load. It either displays a white screen, or it shows the little "page could not be displayed" icon:
I have been unable to reliably duplicate this bug
I have not seen a clear pattern between computers that can and cannot view the iframe content.
All clients are running google chrome, most on an apple powermac. The only semi-link I have made is that windows computers seem slightly more susceptible to it, but not in a way I can reproduce. Sometimes refreshing the page works...
Are there any known bugs that could possibly cause this to happen? I have read about iframe white flashes but I am confident it isn't that issue. I am confident it isn't a problem with jQuery loading because that produces issues before this and would be easy to spot.
Thanks so much.
Alex
edit: Ok so here is the code that is collecting data from the server. Upon inspection the data being received is correct.
conn.on('data', function(data) {
var data_array = JSON.parse(data);
console.log(data_array);
// initialisation
if(data_array.type=='init' && inititated === false) {
if(data_array.duration > 0) {
set_timeleft(data_array.duration); // how long is the exam? (minutes)
} else {
$('#connection_remainingtime').html('No limits');
}
$('#content_frame').attr("src", data_array.uri); // url to navigate to
//timestarted = data_array.start.replace(/ /g,''); // start time
ob = data_array.ob; // is it open book? Doesnt do anything really... why use it if it isnt open book?
snd = data_array.snd; // is sound allowed?
inititated = true;
}
}
It is definitele trying to make the iframe navigate somewhere as when the client launches the iframe changes - its trying to load something but failing.
EDIT: Update on this issue: It does actually work, just not with google forms. And again it isn't everybody's computers, it is only a few people. If they navigate elsewhere (http://www.bit-tech.net for example) then it works just fine.
** FURTHER UPDATE **: It seems on the ones that fail, there is an 'X-Frames-Origin' issue, in that its set the 'SAMEORIGIN'. I dont understand why some students would get this problem and some wouldn't... surely it depends upon the page you are navigating to, and if one person can get it all should be able to?
So the problem here was that the students were trying to load this behind a proxy server which has an issue with cookies. Although the site does not use cookies, the proxy does, and when the student had blocked "third party cookies" in their settings then the proxy was not allowing the site to load.
Simply allowed cookies and it worked :)
iframes are one of the last things to load in the DOM, so wrap your iframe dependent code in this:
document.getElementById('content_frame').onload = function() {...}
If that doesn't work then it's the document within the iframe. If you own the page inside the iframe then you have options. If not...setTimeout? Or window.onload...?
SNIPPET
conn.on('data', function(data) {
var data_array = JSON.parse(data);
console.log(data_array);
// initialisation
if (data_array.type == 'init' && inititated === false) {
if (data_array.duration > 0) {
set_timeleft(data_array.duration); // how long is the exam? (minutes)
} else {
$('#connection_remainingtime').html('No limits');
}
document.getElementById('content_frame').onload = function() {
$('#content_frame').attr("src", data_array.uri); // url to navigate to
//timestarted = data_array.start.replace(/ /g,''); // start time
ob = data_array.ob; // is it open book? Doesnt do anything really... why use it if it isnt open book?
snd = data_array.snd; // is sound allowed?
inititated = true;
}
}
}

How to capture screenshot of parts of the client "desktop" using HTML/JavaScript ?

I know how to capture webpage, but I am asking to how capture desktop or another application in the desktop ? And if there is anyway to highlight parts of screen. Like how html2canvas does for webpages, can we do something for desktop applications using a browser app in HTML/JS ?
Yes, it is possible!But as far as I know only for Firefox and Chrome (I used Chrome). Thanks to Screen Capturing and WebRTC. More info about WebRTC
I used a library called RTCMultiConnection which is very easy to use, but you should be able to do that also without any use of a library.
Here, just to give you a startingpoint:
// 1. Create the connection Objekt
var connection = new RTCMultiConnection();
// 2. Activate screen, which is the whole monitor, not only the browser window!
connection.session = {
screen: true,
data: false,
oneway: true
};
// 3. Create the callback for the stream
connection.onstream = function(event) {
// Make something with the event
// event.stream contains the stream, event.mediaElement the media
// I used event.mediaElement as parameter to draw the frage into an canvas; via context2d.drawImage(event.mediaElement, ...)
// Then I create an base64 String via canvas.toDataURL("image/png") and
// Don't forget to stop the stream if you just want to have one single image
};
// 4. Start Desktop Sharing
connection.open({
// you could register a onMediaCaptured callback here
});

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