Clean up directory structure (#426)

* Remove unused circular-buffer crate
* Move transports into subdirectory
* Move misc into subdirectory
* Move stores into subdirectory
* Move multiplexers
* Move protocols
* Move libp2p top layer
* Fix Test: skip doctest if secio isn't enabled

examples/echo-server.rs

@@ -0,0 +1,143 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+extern crate bytes;
+extern crate env_logger;
+extern crate futures;
+extern crate libp2p;
+extern crate tokio_codec;
+extern crate tokio_current_thread;
+
+use futures::future::{loop_fn, Future, IntoFuture, Loop};
+use futures::{Sink, Stream};
+use std::env;
+use libp2p::SimpleProtocol;
+use libp2p::core::Transport;
+use libp2p::core::{upgrade, either::EitherOutput};
+use libp2p::tcp::TcpConfig;
+use tokio_codec::{BytesCodec, Framed};
+use libp2p::websocket::WsConfig;
+
+fn main() {
+    env_logger::init();
+
+    // Determine which address to listen to.
+    let listen_addr = env::args()
+        .nth(1)
+        .unwrap_or("/ip4/0.0.0.0/tcp/10333".to_owned());
+
+    // We start by creating a `TcpConfig` that indicates that we want TCP/IP.
+    let transport = TcpConfig::new()
+        // In addition to TCP/IP, we also want to support the Websockets protocol on top of TCP/IP.
+        // The parameter passed to `WsConfig::new()` must be an implementation of `Transport` to be
+        // used for the underlying multiaddress.
+        .or_transport(WsConfig::new(TcpConfig::new()))
+
+        // On top of TCP/IP, we will use either the plaintext protocol or the secio protocol,
+        // depending on which one the remote supports.
+        .with_upgrade({
+            let plain_text = upgrade::PlainTextConfig;
+
+            let secio = {
+                let private_key = include_bytes!("test-rsa-private-key.pk8");
+                let public_key = include_bytes!("test-rsa-public-key.der").to_vec();
+                libp2p::secio::SecioConfig {
+                    key: libp2p::secio::SecioKeyPair::rsa_from_pkcs8(private_key, public_key).unwrap(),
+                }
+            };
+
+            upgrade::or(
+                upgrade::map(plain_text, |pt| EitherOutput::First(pt)),
+                upgrade::map(secio, |out: libp2p::secio::SecioOutput<_>| EitherOutput::Second(out.stream))
+            )
+        })
+
+        // On top of plaintext or secio, we will use the multiplex protocol.
+        .with_upgrade(libp2p::mplex::MplexConfig::new())
+        // The object returned by the call to `with_upgrade(MplexConfig::new())` can't be used as a
+        // `Transport` because the output of the upgrade is not a stream but a controller for
+        // muxing. We have to explicitly call `into_connection_reuse()` in order to turn this into
+        // a `Transport`.
+        .into_connection_reuse();
+
+    // We now have a `transport` variable that can be used either to dial nodes or listen to
+    // incoming connections, and that will automatically apply secio and multiplex on top
+    // of any opened stream.
+
+    // We now prepare the protocol that we are going to negotiate with nodes that open a connection
+    // or substream to our server.
+    let proto = SimpleProtocol::new("/echo/1.0.0", |socket| {
+        // This closure is called whenever a stream using the "echo" protocol has been
+        // successfully negotiated. The parameter is the raw socket (implements the AsyncRead
+        // and AsyncWrite traits), and the closure must return an implementation of
+        // `IntoFuture` that can yield any type of object.
+        Ok(Framed::new(socket, BytesCodec::new()))
+    });
+
+    // Let's put this `transport` into a *swarm*. The swarm will handle all the incoming and
+    // outgoing connections for us.
+    let (swarm_controller, swarm_future) = libp2p::core::swarm(
+        transport.clone().with_upgrade(proto),
+        |socket, _client_addr| {
+            println!("Successfully negotiated protocol");
+
+            // The type of `socket` is exactly what the closure of `SimpleProtocol` returns.
+
+            // We loop forever in order to handle all the messages sent by the client.
+            loop_fn(socket, move |socket| {
+                socket
+                    .into_future()
+                    .map_err(|(e, _)| e)
+                    .and_then(move |(msg, rest)| {
+                        if let Some(msg) = msg {
+                            // One message has been received. We send it back to the client.
+                            println!(
+                                "Received a message: {:?}\n => Sending back \
+                                 identical message to remote", msg
+                            );
+                            Box::new(rest.send(msg.freeze()).map(|m| Loop::Continue(m)))
+                                as Box<Future<Item = _, Error = _>>
+                        } else {
+                            // End of stream. Connection closed. Breaking the loop.
+                            println!("Received EOF\n => Dropping connection");
+                            Box::new(Ok(Loop::Break(())).into_future())
+                                as Box<Future<Item = _, Error = _>>
+                        }
+                    })
+            })
+        },
+    );
+
+    // We now use the controller to listen on the address.
+    let address = swarm_controller
+        .listen_on(listen_addr.parse().expect("invalid multiaddr"))
+        // If the multiaddr protocol exists but is not supported, then we get an error containing
+        // the original multiaddress.
+        .expect("unsupported multiaddr");
+    // The address we actually listen on can be different from the address that was passed to
+    // the `listen_on` function. For example if you pass `/ip4/0.0.0.0/tcp/0`, then the port `0`
+    // will be replaced with the actual port.
+    println!("Now listening on {:?}", address);
+
+    // `swarm_future` is a future that contains all the behaviour that we want, but nothing has
+    // actually started yet. Because we created the `TcpConfig` with tokio, we need to run the
+    // future through the tokio core.
+    tokio_current_thread::block_on_all(swarm_future).unwrap();
+}