[Feature] Interfaces design flaw

[sitano]

Currently, the interfaces (i.e. EventInterface) can't be implemented for any external object because they inherit ClientLike that has unpublished RedisClientInner.

Describe the solution you'd like

Either make interfaces not to inherit : ClientLike {} interface that can't be implemented externally for wrappers

pub trait EventInterface { ... }

or change ClientLike to be implementable outside of Fred

pub trait ClientLike: Clone + Send + Sync + Sized {
  #[doc(hidden)]
  fn client(&self) -> &Arc<RedisClient>;
}

and maybe minimize trait itself.

Additional context

I want to do basically this:

pub struct MyClient {
    inner: Arc<Inner>,
}

struct Inner {
    client: Arc<fred::clients::SubscriberClient>,
}

// OOOOOOPS: without this EventInterface would not do
impl ClientLike for MyClient {
  // OOOOOOPS: that's impossible cuz RedisClientInner is inner
  fn inner(&self) -> &RefCount<RedisClientInner> {
    &self.inner
  }
}

impl EventInterface for MyClient {}

[aembke]

Hi @sitano, thanks for bringing this up. I hadn't originally intended for folks to implement that trait, but I can see why it would be useful in cases like this. I'm working on a fairly substantial refactor to support this by breaking up the interfaces and semi-public types like ClientInner into separate crates, which should allow for this kind of usage and should hopefully speed up compilation times.

Unfortunately something changed with openssl last week and CI runs are now failing across the board for anything related to TLS (even ones from months ago that passed previously), so it may be a couple weeks before I have a chance to push this, but I may ping you for some early feedback on the new interfaces if that works for you.