Comment by gwern
11 days ago
> that this is an implementation detail which is not really related to the format. In this case, a polyglot zip/html file could also interrupt page loading via a window.stop() call...However, I admit that I haven't implemented this mechanism yet.
Well, yes. That's why we created Gwtar and I didn't just use SingleFileZ. We would have preferred to not go to all this trouble and use someone else's maintained tool, but if it's not implemented, then I can't use it.
(Also, if it had been obvious to you how to do this window.stop+range-request trick beforehand, and you just hadn't gotten around to implementing it, it would have been nice if you had written it up somewhere more prominent; I was unable to find any prior art or discussion.)
The reason I did not implement the innovative mechanism you describe is because, in my case, all the technical effort was/is focused on reading the archive from the filesystem. No one has suggested it either.
Edit: Actually, SingleFile already calls window.stop() when displaying a zip/html file from HTTP, see https://github.com/gildas-lormeau/single-file-core/blob/22fc...
What does that do?
The call to window.stop() stops HTML parsing/rendering, which is unnecessary since the script has downloaded the page via HTTP and will decompress it as-is as a binary file (zip.js supports concatenated payloads before and after the zip data). However, in my case, the call to window.stop() is executed asynchronously once the binary has been downloaded, and therefore may be too late. This is probably less effective than in your case with gtwar.
I implemented this in the simplest way possible because if the zip file is read from the filesystem, window.stop() must not be called immediately because the file must be parsed entirely. In my case, it would require slightly more complex logic to call window.stop() as early as possible.
Edit: Maybe it's totally useless though, as documented here [1]: "Because of how scripts are executed, this method cannot interrupt its parent document's loading, but it will stop its images, new windows, and other still-loading objects." (you mentioned it in the article)
[1] https://developer.mozilla.org/en-US/docs/Web/API/Window/stop
Edit #2: Since I didn't know that window.call() was most likely useless in my case, I understand your approach much better now. Thank you very much for clarifying that with your question!
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