File system which reads/writes to indexeddb without syncing with memfs

[andersson09]

Hi,

Will there be any plans to provide a file system which stores directly to indexeddb? It would be very useful to be able to read individual large files with streams without loading everything in memory. Also would remove then need of having to manually call syncfs. I know there's a library which can call the db from code but would be much better for it to occur lower level as part of the file system.

Thanks

[kripken]

IndexedDB is async, which makes this hard. Storing directly to IDB would require pthreads or asyncify or some other way to bridge the sync/async API gap.

I do hope that we add a pthreads version of that eventually in the new filesystem work: #15041

[andersson09]

So this feature is already confirmed in the new filesystem work?

[kripken]

It's something I'd like to see happen, but there isn't a specific plan for someone to work on it yet. First we need to finish the general setup of the new FS which is ongoing atm.

[andersson09]

It's something I'd like to see happen, but there isn't a specific plan for someone to work on it yet. First we need to finish the general setup of the new FS which is ongoing atm.

OK let's hope it happens since I think it's pretty fundamental.

[andersson09]

IndexedDB is async, which makes this hard. Storing directly to IDB would require pthreads or asyncify or some other way to bridge the sync/async API gap.

I do hope that we add a pthreads version of that eventually in the new filesystem work: #15041

Just had a read through the filesystem work. I was wondering how this will impact standalone wasi since some of the code is going from js to webassembly. Also whether the new js library can be utilised for existing js wasi bindings?

[kripken]

@andersson09 In general as we move code from JS to wasm it makes supporting standalone mode easier. So that will help WASI.

Using the new FS code for WASI bindings could work, but would probably need a little extra support code (e.g. where we use POSIX things not in WASI, they'd need to be lowered somehow).