71–80 of 166 posts
This isn't really JS, it's a purpose built evaluator that's only for evaluating a particular script on YouTube, assuming a huge list of things are true about how YouTube JS is written. Ex. Its got a hard coded list of methods for String, and it doesn't respect prototypes. It only supports creating Date instances, and won't work if you override the global Date. It parses with regexes and implements all operators with…
Submitted title was "YouTube-dl has a JavaScript interpreter written in 870 lines of Python".
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I'm trying to get the thread model here. Is the concern that Youtube will inject JS into the payload which tries to break out of the youtuble-dl js sandbox using some zero day in whatever js engine they would use instead?
Embedding a whole js engine and then interopping with it from python would be non trivial. Good luck fixing any bugs or corner cases you hit that way. The V8 and spidermonkey embedding apis are both c++ (iirc) and non trivial to use correctly. Having full control like this +simple code is probably lower risk and more maintainable, even if there's the challenge of expanding feature set if scripts change. The alternati…
https://github.com/PetterS/quickjs
https://github.com/stefano/pyduktape
https://github.com/amol-/dukpy
I can't speak to the quality of those bindings, but they do seem maintained.
Or is their goal just to make youtube-dl not 100% reliable? Or to be able to say "look, you are running our code in a way we did not intend, you can't do this because you are breaking the EULA"?
Earlier quoted context omitted.
I'm trying to get the thread model here. Is the concern that Youtube will inject JS into the payload which tries to break out of the youtuble-dl js sandbox using some zero day in whatever js engine they would use instead?
Embedding a whole js engine and then interopping with it from python would be non trivial. Good luck fixing any bugs or corner cases you hit that way. The V8 and spidermonkey embedding apis are both c++ (iirc) and non trivial to use correctly. Having full control like this +simple code is probably lower risk and more maintainable, even if there's the challenge of expanding feature set if scripts change. The alternati…
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Quoted post unavailable.
> you also think billionares should be taxed more That's... quite a response in defense of a tool intended for breaching TOS and performing copyright infringement. Can you clarify exactly who it is and isn't OK to steal from, again? I'm struggling here.
Does using a different User Agent instead of a typical browser amount to copyright infringement in any jurisdiction?
I do wonder why YouTube does not try harder to make it difficult to do this computation meant to prove you are a legit YouTube web client. Providing an easy-to-find, simple JS function interpretable with 900 lines of Python is like they don't try at all. They might as well do nothing. Or is their goal just to make youtube-dl not 100% reliable? Or to be able to say "look, you are running our code in a way we did not i…
https://github.com/yt-dlp/yt-dlp/issues/4635#issuecomment-12...
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It's their platform. They can do with it what they want.
Many channels would be more than happy to enable download options, if possible. Hell, how is Creative Commons licence they totally give you option to select, work in case of videos that can't be downloaded in any way?
What purpose does it serve?
I'd have to read up on the specifics as well, but I think basically Youtube uses a lot of obfuscated, rapidly and automatically changing Javascript code to fetch the video data. A project like youtube-dl has to run this code to be able to download videos, because that's what's happening in the browser as well.
It's kinda annoying if you have a lot of youtube tabs open for a long time and come back to them.