How do I access state that is Send + !Sync in Axum?

[Zk2u]

I have a database, namely Sled, whose database is designed to be cloned rather than shared in an Arc. Each database clone is a handle to the same database. How can I access that database from the handlers?

[davidpdrsn]

That should just work. You have to provide more details if it doesn’t work for you.

[Zk2u]

I've used thread local storage for it to work as expected without having to go through Axum's state. Thank you for an awesome library!

/// CELL is shared between ALL threads
static CELL: OnceLock<Mutex<sled::Db>> = OnceLock::new();

thread_local! {
    /// Thread local DB clone
    static DB: Rc<sled::Db> = Rc::new(CELL.get_or_init(|| {
        debug!("DB open on thread {}", std::thread::current().name().unwrap_or("unknown"));
        Mutex::new({
            let mut config = sled::Config::default();
            config.flush_every_ms = None;
            sled::Db::open_with_config(&config).unwrap()
        })
    }).lock().unwrap().clone());
}

pub fn thread_local_db() -> Rc<sled::Db> {
    DB.with(|db| db.clone())
}