From f6b53ec5865720a2937bc238ee75d72588e10cce Mon Sep 17 00:00:00 2001
From: Robert Habermeier <rphmeier@gmail.com>
Date: Sat, 8 Apr 2017 18:22:22 +0200
Subject: [PATCH] minimal host interface

---
 Cargo.toml                  |  2 +-
 libp2p-transport/Cargo.toml |  1 -
 libp2p-transport/src/lib.rs | 74 +++++++++----------------------------
 3 files changed, 18 insertions(+), 59 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index b74045c0..e8ef317d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,4 +4,4 @@ version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 
 [workspace]
-members = ["libp2p-transport"]
\ No newline at end of file
+members = ["libp2p-transport", "libp2p-host"]
\ No newline at end of file
diff --git a/libp2p-transport/Cargo.toml b/libp2p-transport/Cargo.toml
index d922893f..9cdc337f 100644
--- a/libp2p-transport/Cargo.toml
+++ b/libp2p-transport/Cargo.toml
@@ -2,7 +2,6 @@
 name = "libp2p-transport"
 version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
-workspace = ".."
 
 [dependencies]
 multiaddr = "0.2.0"
diff --git a/libp2p-transport/src/lib.rs b/libp2p-transport/src/lib.rs
index 1a3e78e0..72902b3b 100644
--- a/libp2p-transport/src/lib.rs
+++ b/libp2p-transport/src/lib.rs
@@ -1,4 +1,4 @@
-//! Rust libp2p implementation
+//! Transport and I/O primitives for libp2p.
 
 extern crate futures;
 extern crate tokio_io;
@@ -21,10 +21,6 @@ pub type PeerId = String;
 /// A logical wire between us and a peer. We can read and write through this asynchronously.
 ///
 /// You can have multiple `Socket`s between you and any given peer.
-//
-// What do we call it? Go-libp2p calls them "Streams", but "Streams" in futures-rs specifically
-// denote the "writing" half. "Connections" have a different meaning in the libp2p definition.
-// `Duplex`?
 pub trait Socket: AsyncRead + AsyncWrite { 
     /// Get the protocol ID this socket uses.
     fn protocol_id(&self) -> ProtocolId;
@@ -42,61 +38,25 @@ pub trait Conn {
     fn make_socket(&self, proto: ProtocolId) -> BoxFuture<Self::Socket, IoError>;
 }
 
-/// Produces a future for each incoming `Socket`.
-pub trait Handler<S: Socket> {
-    type Future: IntoFuture<Item=(), Error=()>;
-
-    /// Handle the incoming socket, producing a future which should resolve 
-    /// when the handler is finished.
-    fn handle(&self, socket: S) -> Self::Future;
-    fn boxed(self) -> BoxHandler<S> where 
-        Self: Sized + Send + 'static, 
-        <Self::Future as IntoFuture>::Future: Send + 'static
-    {
-        BoxHandler(Box::new(move |socket|
-            self.handle(socket).into_future().boxed()
-        ))
-    }
-}
-
-impl<S: Socket, F, U> Handler<S> for F 
-    where F: Fn(S) -> U, U: IntoFuture<Item=(), Error=()>
-{
-    type Future = U;
-
-    fn handle(&self, socket: S) -> U { (self)(socket) }
-}
-
-/// A boxed handler.
-pub struct BoxHandler<S: Socket>(Box<Handler<S, Future=BoxFuture<(), ()>>>);
-
-impl<S: Socket> Handler<S> for BoxHandler<S> {
-    type Future = BoxFuture<(), ()>;
-
-    fn handle(&self, socket: S) -> Self::Future {
-        self.0.handle(socket)
-    }
-}
-
-/// Multiplexes sockets onto handlers by protocol-id.
-pub trait Mux: Sync {
-    /// The socket type this manages.
-    type Socket: Socket;
-
-    /// Attach an incoming socket.
-    fn push(&self, socket: Self::Socket);
-  
-    /// Set the socket handler for a given protocol id.
-    fn set_handler(&self, proto: ProtocolId, handler: BoxHandler<Self::Socket>);
-
-    /// Remove the socket handler for the given protocol id, returning the old handler if it existed.
-    fn remove_handler(&self, proto: &ProtocolId) -> Option<BoxHandler<Self::Socket>>;
-}
-  
 pub struct MultiAddr; // stub for multiaddr crate type.
 
 /// A transport is a stream producing incoming connections.
 /// These are transports or wrappers around them.
+//
+// Listening/Dialing hasn't really been sorted out yet.
+// It's easy to do for simple multiaddrs, but for complex ones,
+// particularly those with multiple hops, things get much fuzzier.
+//
+// One example which is difficult to make work is something like 
+// `ip4/1.2.3.4/tcp/8888/p2p-circuit/p2p/DestPeer`
+// 
+// This address, when used for dialing, says "Connect to the peer DestPeer
+// on any available address, through a relay node we will connect to via 
+// tcp on port 8888 over the ipv4 address 1.2.3.4"
+//
+// We'll need to require dialers to handle the whole address,
+// and give them a closure or similar required to instantiate connections 
+// to different multi-addresses.
 pub trait Transport {
     /// The raw connection.
     type RawConn: AsyncRead + AsyncWrite;
@@ -113,6 +73,6 @@ pub trait Transport {
 
     /// Dial to the given multi-addr.
     /// Returns either a future which may resolve to a connection,
-    /// or 
+    /// or gives back the multiaddress.
     fn dial(&mut self, addr: MultiAddr) -> Result<Self::Dial, MultiAddr>;
 }
\ No newline at end of file