Support Sqlite storage type

[Half-Shot]

As part of my quest to look at moving the bots and bridges away from the nodejs binding layer, I'd like to talk about potentially enabling SQLite support for this binding layer. In the NodeJS project, we do https://github.com/matrix-org/matrix-rust-sdk-crypto-nodejs/blob/main/src/machine.rs#L113-L155.

[richvdh]

I guess this would require the use of Sqlite's support for wasm. Not sure what would be involved in wiring that up.

[Hywan]

I don't think we should use Sqlite compiled as Wasm. Instead, we should expose SQLite API via Wasm imports, and use SQLite compiled as a NodeJS bindings from C. It would be probably much faster and easier.

[richvdh]

Instead, we should expose SQLite API via Wasm imports

You mean, build our own wrapper around the sqlite API, and somehow thread that through to the rust layer? That sounds like a lot of work.

[Hywan]

It's probably a lot of work because the Matrix Rust SDK expects rusqlite API entirely. I wonder how it compiles to wasm32-unknown-unknown and how linking is done. We should try.

It's probably more work than maintaining matrix-rust-sdk-crypto-nodejs if you ask me 😛.

[Half-Shot]

Well, the issue exists because nobody really maintains matrix-rust-sdk-crypto-nodejs right now and that leads to the integrations lagging behind the clients, causing people to pull out their hair.

But if doing the work to make our integrations support the maintained wasm bindings is more work than just having someone maintain the nodejs bindings, then that's fine too. The current situation is untenable though.

[richvdh]

Other than the overhead of maintaining two sets of bindings, another advantage of supporting sqlite through the wasm bindings rather than maintaining matrix-rust-sdk-crypto-nodejs would be that you could also use matrix-js-sdk for nodejs projects.

[richvdh]

Yet another option here might be to use https://www.npmjs.com/package/indexeddb, which implements indexeddb backed by the local filesystem. That said, its 35 weekly downloads aren't entirely reassuring.

[Half-Shot]

it's vintage 🍷

[richvdh]

In fairness 0.0.1 was only published 4 years ago. I guess if it works, don't change it?