Derive Macro DbContextKey 

#[derive(DbContextKey)]
{
    // Attributes available to this derive:
    #[key]
}

Derive a typed keyed-DbContext key.

The enum’s variants become IDbContextKey::name() values (snake-case by default, overridable with #[key("...")]) and the type implements From<Key> for rust_dix::ServiceKey. This makes #[inject(owned, key = Key::Read)] and add_dbcontext_keyed(Key::Read, ...) share the same typed key.

#[derive(DbContextKey, Debug, Clone, Copy, PartialEq, Eq, Hash)]
enum Db {
    Read,
    Write,
    #[key("audit-log")]
    Audit,
}

The enum must derive Debug + Clone + Copy + PartialEq + Eq + Hash (the bounds required by rust_dix::ServiceKey::new).