lazyFileLRU

mount remote file by URL to Emscripten fillesystem, with LRU buffer

This project builds on the lazyFile implementation in https://github.com/phiresky/sql.js-httpvfs. In that implementation, the chunks are inserted (sparsely) into a javascript Array as they are loaded.

Here an LRU buffer (from typescript-lru-cache) is used instead of an Array, with user-specified max size.

The same caveats apply to this as the original: it must be run in a web worker as it relies on synchronous fetch operations.

An example worker is specified in ./src/adv_worker.ts, (and compiled in ./dist/adv_worker.js)

Demo

The example can be tried at https://bmaranville.github.io/lazyFileLRU/ (the HDF5 file to be loaded must be on a server with range requests enabled, and compression disabled)

1. Enter a URL into the File URL: field
2. Click load
3. Enter an HDF5 path into the path field
4. Click get

(look at the network requests in the developer panel to see all the chunks being loaded)