PSA: Type-privacy

[thomaseizinger]

For a while now, we've been making many modules in our plugins private to be able to "freely" modify them. This especially concerns implementations of ConnectionHandler and the events around it.

Well, I've got bad news: They are not actually private.

It is completely legal to write this today¹:

let event = <<<Behaviour<MemoryStore> as NetworkBehaviour>::ConnectionHandler as ConnectionHandler>::ToBehaviour>::ProtocolNotSupported { endpoint: ConnectedPoint::Dialer { address: Multiaddr::empty(), role_override: Endpoint::Dialer } };

And bam, you've constructed yourself an event that is only meant to be sent by the ConnectionHandler to the NetworkBehaviour. Not sure what to do about this yet but I am leaning towards documenting that these aren't actually public API and doing these kind of shenanigans is setting yourself up for bad times.

Footnotes

1. On nightly. It needs the #![feature(more_qualified_paths)] but I am assuming this will stabilise eventually. ↩

[mxinden]

And bam, you've constructed yourself an event that is only meant to be sent by the ConnectionHandler to the NetworkBehaviour. Not sure what to do about this yet but I am leaning towards documenting that these aren't actually public API and doing these kind of shenanigans is setting yourself up for bad times.

👍 sounds good to me.