fac-rs VS apsw

I wrote a similar thing in Rust for a Factorio mod manager - mods are hosted on the remote HTTP server as ZIP files and the mod manager needs a single info.json file from the ZIP for the mod metadata, so it avoids downloading the whole mod and then unpacking it by building a file abstraction that uses HTTP range queries to download chunks. For ZIP files the directory is stored at the end at an unknown offset, so the read pattern is to gradually seek backwards from the end until you find the start of the directory, then find the file entry, then read the file.

I didn't fiddle with the window sizes like the TFA, but I did optimize it so that reading chunk N+1 of the file reused the response readed of chunk N rather than making a new request. Furthermore I keep an LRU cache of the last three chunks rather than keep all of them in memory, because the ZIP files are each only read once.

[1]: https://github.com/Arnavion/fac-rs/blob/master/src/solve/web...

[2]: https://github.com/Arnavion/fac-rs/blob/master/src/solve/zip...

You can do this with virtual tables, but you'd have to implement the code for the vtab yourself. If you know Python, the APSW SQLite driver supports vtabs. The default one that comes with most Python distros does not

There is also this, which seems pretty good: https://github.com/rogerbinns/apsw

(haven't tried it yet)