Implement AsyncRead + AsyncWrite for bidirectional stream as a single type.

[TheButlah]

Implement AsyncRead + AsyncWrite for bidirectional stream as a single type.

[BiagioFesta]

Hi,

The general idea is to follow the same approach used in the underlying QUIC library which makes sense to me.

With this approach only 2 types are requires (SendStream and RecvStream) providing simple and immediate API. They are 2 very well defined objects providing the 2 different functionalities (send and receive), single-responsibility principle.

Other libraries might introduce composite types. For example, s2n-quic, another QUIC library, uses multiple types and stream-functions: https://docs.rs/s2n-quic/latest/s2n_quic/connection/struct.Connection.html#
Multiple accept_* function with enum variants.

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Maybe it was to unify the types with the unidirectional stream? (if that is the case, there can be a .split() function on this joined type that turns it into the two streams).

Indeed, this is true as well. I would avoid having UnidirectionalRecv, UnidirectionalSend and Bidirectional (for a total of 3 types) where Bidirectional overlaps code/functionalities.

However, I am not sure understanding your suggestion. How split works with unidirectional stream? (I would imagine split for bidirectional).

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Moreover, current SendStream and RecvStream can be easily composable. I reckon you mentioned this, but I don't see how this might be complicated.

pub struct BiStream((SendStream, RecvStream));

impl AsyncRead BiStream { ... }

impl AsyncWrite BiStream { ... }

Maybe you can provide some code example also here, so we can see if we can find a better solution providing some helpers directly in wtransport.

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Side note: calling them streams is a bit confusing, because they implement AsyncWrite/Read rather than Stream or Sink. (Edit: I guess this was done because the webtransport api calls them streams).

Yeah :)

This is a little bit inconvenient, but QUIC works with Streams.

Thanks

[BiagioFesta]

Can you please have a look at: #135

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