refactor(core)!: remove EitherTransport (#3338)

We don't need to define our own type here, we can simply implement `Transport` on `either::Either`.

Author: thomaseizinger

core/CHANGELOG.md

@@ -14,12 +14,15 @@
 
 - Remove `EitherError` in favor of `either::Either`. See [PR 3337].
 
+- Remove `EitherTransport` in favor of implementing `Transport` on `either::Either`. See [PR 3338].
+
 [PR 3031]: https://github.com/libp2p/rust-libp2p/pull/3031
 [PR 3058]: https://github.com/libp2p/rust-libp2p/pull/3058
 [PR 3097]: https://github.com/libp2p/rust-libp2p/pull/3097
 [PR 3090]: https://github.com/libp2p/rust-libp2p/pull/3090
 [PR 2972]: https://github.com/libp2p/rust-libp2p/pull/2972
 [PR 3337]: https://github.com/libp2p/rust-libp2p/pull/3337
+[PR 3338]: https://github.com/libp2p/rust-libp2p/pull/3338
 
 # 0.37.0
 

core/src/either.rs

@@ -293,15 +293,8 @@ impl<A: ProtocolName, B: ProtocolName> ProtocolName for EitherName<A, B> {
         }
     }
 }
-#[pin_project(project = EitherTransportProj)]
-#[derive(Debug)]
-#[must_use = "transports do nothing unless polled"]
-pub enum EitherTransport<A, B> {
-    Left(#[pin] A),
-    Right(#[pin] B),
-}
 
-impl<A, B> Transport for EitherTransport<A, B>
+impl<A, B> Transport for Either<A, B>
 where
     B: Transport,
     A: Transport,
@@ -315,14 +308,14 @@ where
         self: Pin<&mut Self>,
         cx: &mut Context<'_>,
     ) -> Poll<TransportEvent<Self::ListenerUpgrade, Self::Error>> {
-        match self.project() {
-            EitherTransportProj::Left(a) => match a.poll(cx) {
+        match self.as_pin_mut() {
+            Either::Left(a) => match a.poll(cx) {
                 Poll::Pending => Poll::Pending,
                 Poll::Ready(event) => {
                     Poll::Ready(event.map_upgrade(EitherFuture::First).map_err(Either::Left))
                 }
             },
-            EitherTransportProj::Right(b) => match b.poll(cx) {
+            Either::Right(b) => match b.poll(cx) {
                 Poll::Pending => Poll::Pending,
                 Poll::Ready(event) => Poll::Ready(
                     event
@@ -335,19 +328,19 @@ where
 
     fn remove_listener(&mut self, id: ListenerId) -> bool {
         match self {
-            EitherTransport::Left(t) => t.remove_listener(id),
-            EitherTransport::Right(t) => t.remove_listener(id),
+            Either::Left(t) => t.remove_listener(id),
+            Either::Right(t) => t.remove_listener(id),
         }
     }
 
     fn listen_on(&mut self, addr: Multiaddr) -> Result<ListenerId, TransportError<Self::Error>> {
         use TransportError::*;
         match self {
-            EitherTransport::Left(a) => a.listen_on(addr).map_err(|e| match e {
+            Either::Left(a) => a.listen_on(addr).map_err(|e| match e {
                 MultiaddrNotSupported(addr) => MultiaddrNotSupported(addr),
                 Other(err) => Other(Either::Left(err)),
             }),
-            EitherTransport::Right(b) => b.listen_on(addr).map_err(|e| match e {
+            Either::Right(b) => b.listen_on(addr).map_err(|e| match e {
                 MultiaddrNotSupported(addr) => MultiaddrNotSupported(addr),
                 Other(err) => Other(Either::Right(err)),
             }),
@@ -357,12 +350,12 @@ where
     fn dial(&mut self, addr: Multiaddr) -> Result<Self::Dial, TransportError<Self::Error>> {
         use TransportError::*;
         match self {
-            EitherTransport::Left(a) => match a.dial(addr) {
+            Either::Left(a) => match a.dial(addr) {
                 Ok(connec) => Ok(EitherFuture::First(connec)),
                 Err(MultiaddrNotSupported(addr)) => Err(MultiaddrNotSupported(addr)),
                 Err(Other(err)) => Err(Other(Either::Left(err))),
             },
-            EitherTransport::Right(b) => match b.dial(addr) {
+            Either::Right(b) => match b.dial(addr) {
                 Ok(connec) => Ok(EitherFuture::Second(connec)),
                 Err(MultiaddrNotSupported(addr)) => Err(MultiaddrNotSupported(addr)),
                 Err(Other(err)) => Err(Other(Either::Right(err))),
@@ -379,12 +372,12 @@ where
     {
         use TransportError::*;
         match self {
-            EitherTransport::Left(a) => match a.dial_as_listener(addr) {
+            Either::Left(a) => match a.dial_as_listener(addr) {
                 Ok(connec) => Ok(EitherFuture::First(connec)),
                 Err(MultiaddrNotSupported(addr)) => Err(MultiaddrNotSupported(addr)),
                 Err(Other(err)) => Err(Other(Either::Left(err))),
             },
-            EitherTransport::Right(b) => match b.dial_as_listener(addr) {
+            Either::Right(b) => match b.dial_as_listener(addr) {
                 Ok(connec) => Ok(EitherFuture::Second(connec)),
                 Err(MultiaddrNotSupported(addr)) => Err(MultiaddrNotSupported(addr)),
                 Err(Other(err)) => Err(Other(Either::Right(err))),
@@ -394,8 +387,8 @@ where
 
     fn address_translation(&self, server: &Multiaddr, observed: &Multiaddr) -> Option<Multiaddr> {
         match self {
-            EitherTransport::Left(a) => a.address_translation(server, observed),
-            EitherTransport::Right(b) => b.address_translation(server, observed),
+            Either::Left(a) => a.address_translation(server, observed),
+            Either::Right(b) => b.address_translation(server, observed),
         }
     }
 }

examples/ipfs-private.rs

@@ -32,11 +32,10 @@
 //! You can ping this node, or use pubsub (gossipsub) on the topic "chat". For this
 //! to work, the ipfs node needs to be configured to use gossipsub.
 use async_std::io;
+use either::Either;
 use futures::{prelude::*, select};
 use libp2p::{
-    core::{
-        either::EitherTransport, muxing::StreamMuxerBox, transport, transport::upgrade::Version,
-    },
+    core::{muxing::StreamMuxerBox, transport, transport::upgrade::Version},
     gossipsub::{self, Gossipsub, GossipsubConfigBuilder, GossipsubEvent, MessageAuthenticity},
     identify, identity,
     multiaddr::Protocol,
@@ -59,10 +58,10 @@ pub fn build_transport(
 
     let base_transport = tcp::async_io::Transport::new(tcp::Config::default().nodelay(true));
     let maybe_encrypted = match psk {
-        Some(psk) => EitherTransport::Left(
+        Some(psk) => Either::Left(
             base_transport.and_then(move |socket, _| PnetConfig::new(psk).handshake(socket)),
         ),
-        None => EitherTransport::Right(base_transport),
+        None => Either::Right(base_transport),
     };
     maybe_encrypted
         .upgrade(Version::V1)