Asynchronous when Piping Read Streams to Writable Streams with createWritable()

[FaitAccompli]

Hi,

I'm trying to migrate from StreamSaver to Native File System API. For smaller datasets, streaming the data in my streaming API and saving it as CSV on client side is no issue with file system access. However, for larger datasets with around ~1M rows there are UI issues where the download gets cancelled every time we change routes or click on a different module in the app.

I hope there's a way or workaround for this issue. StreamSaver (https://github.com/jimmywarting/StreamSaver.js) creates a writable stream directly to the file system, the downside to this however is using a service worker. Would it be possible to do so as well with file system access? Maybe making use of the browsers download progress and making the process of piping read streams to writable streams non-blocking when using createWritable().