Fix examples and update core-derive. (#1317)

Cargo.toml

@@ -45,9 +45,8 @@ libp2p-tcp = { version = "0.13.0", path = "transports/tcp" }
 libp2p-websocket = { version = "0.13.0", path = "transports/websocket", optional = true }
 
 [dev-dependencies]
+async-std = "1.0"
 env_logger = "0.7.1"
-tokio = "0.1"
-tokio-stdin-stdout = "0.1"
 
 [workspace]
 members = [

examples/chat.rs

@@ -49,20 +49,21 @@
 //!
 //! The two nodes then connect.
 
-use futures::prelude::*;
+use async_std::{io, task};
+use futures::{future, prelude::*};
 use libp2p::{
+    Multiaddr,
     PeerId,
     Swarm,
     NetworkBehaviour,
     identity,
-    tokio_codec::{FramedRead, LinesCodec},
-    tokio_io::{AsyncRead, AsyncWrite},
     floodsub::{self, Floodsub, FloodsubEvent},
     mdns::{Mdns, MdnsEvent},
     swarm::NetworkBehaviourEventProcess
 };
+use std::{error::Error, task::{Context, Poll}};
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     env_logger::init();
 
     // Create a random PeerId
@@ -71,7 +72,7 @@ fn main() {
     println!("Local peer id: {:?}", local_peer_id);
 
     // Set up a an encrypted DNS-enabled TCP Transport over the Mplex and Yamux protocols
-    let transport = libp2p::build_development_transport(local_key);
+    let transport = libp2p::build_development_transport(local_key)?;
 
     // Create a Floodsub topic
     let floodsub_topic = floodsub::TopicBuilder::new("chat").build();
@@ -87,12 +88,11 @@ fn main() {
     impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<MdnsEvent> for MyBehaviour<TSubstream> {
         fn inject_event(&mut self, event: MdnsEvent) {
             match event {
-                MdnsEvent::Discovered(list) => {
+                MdnsEvent::Discovered(list) =>
                     for (peer, _) in list {
                         self.floodsub.add_node_to_partial_view(peer);
                     }
-                },
+                MdnsEvent::Expired(list) =>
-                MdnsEvent::Expired(list) => {
                     for (peer, _) in list {
                         if !self.mdns.has_node(&peer) {
                             self.floodsub.remove_node_from_partial_view(&peer);
@@ -101,7 +101,6 @@ fn main() {
             }
         }
     }
-    }
 
     impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<FloodsubEvent> for MyBehaviour<TSubstream> {
         // Called when `floodsub` produces an event.
@@ -114,9 +113,10 @@ fn main() {
 
     // Create a Swarm to manage peers and events
     let mut swarm = {
+        let mdns = task::block_on(Mdns::new())?;
         let mut behaviour = MyBehaviour {
             floodsub: Floodsub::new(local_peer_id.clone()),
-            mdns: Mdns::new().expect("Failed to create mDNS service"),
+            mdns
         };
 
         behaviour.floodsub.subscribe(floodsub_topic.clone());
@@ -125,42 +125,32 @@ fn main() {
 
     // Reach out to another node if specified
     if let Some(to_dial) = std::env::args().nth(1) {
-        let dialing = to_dial.clone();
+        let addr: Multiaddr = to_dial.parse()?;
-        match to_dial.parse() {
+        Swarm::dial_addr(&mut swarm, addr)?;
-            Ok(to_dial) => {
+        println!("Dialed {:?}", to_dial)
-                match libp2p::Swarm::dial_addr(&mut swarm, to_dial) {
-                    Ok(_) => println!("Dialed {:?}", dialing),
-                    Err(e) => println!("Dial {:?} failed: {:?}", dialing, e)
-                }
-            },
-            Err(err) => println!("Failed to parse address to dial: {:?}", err),
-        }
     }
 
     // Read full lines from stdin
-    let stdin = tokio_stdin_stdout::stdin(0);
+    let mut stdin = io::BufReader::new(io::stdin()).lines();
-    let mut framed_stdin = FramedRead::new(stdin, LinesCodec::new());
 
     // Listen on all interfaces and whatever port the OS assigns
-    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse().unwrap()).unwrap();
+    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse()?)?;
 
     // Kick it off
     let mut listening = false;
-    tokio::run(futures::future::poll_fn(move || -> Result<_, ()> {
+    task::block_on(future::poll_fn(move |cx: &mut Context| {
         loop {
-            match framed_stdin.poll().expect("Error while polling stdin") {
+            match stdin.try_poll_next_unpin(cx)? {
-                Async::Ready(Some(line)) => swarm.floodsub.publish(&floodsub_topic, line.as_bytes()),
+                Poll::Ready(Some(line)) => swarm.floodsub.publish(&floodsub_topic, line.as_bytes()),
-                Async::Ready(None) => panic!("Stdin closed"),
+                Poll::Ready(None) => panic!("Stdin closed"),
-                Async::NotReady => break,
+                Poll::Pending => break
-            };
+            }
         }
-
         loop {
-            match swarm.poll().expect("Error while polling swarm") {
+            match swarm.poll_next_unpin(cx) {
-                Async::Ready(Some(_)) => {
+                Poll::Ready(Some(event)) => println!("{:?}", event),
-
+                Poll::Ready(None) => return Poll::Ready(Ok(())),
-                },
+                Poll::Pending => {
-                Async::Ready(None) | Async::NotReady => {
                     if !listening {
                         if let Some(a) = Swarm::listeners(&swarm).next() {
                             println!("Listening on {:?}", a);
@@ -171,7 +161,6 @@ fn main() {
                 }
             }
         }
-
+        Poll::Pending
-        Ok(Async::NotReady)
+    }))
-    }));
 }

examples/distributed-key-value-store.rs

@@ -29,19 +29,22 @@
 //!
 //! 4. Close with Ctrl-c.
 
+use async_std::{io, task};
 use futures::prelude::*;
 use libp2p::kad::record::store::MemoryStore;
 use libp2p::kad::{record::Key, Kademlia, KademliaEvent, PutRecordOk, Quorum, Record};
 use libp2p::{
-    build_development_transport, identity,
+    NetworkBehaviour,
+    PeerId,
+    Swarm,
+    build_development_transport,
+    identity,
     mdns::{Mdns, MdnsEvent},
-    swarm::NetworkBehaviourEventProcess,
+    swarm::NetworkBehaviourEventProcess
-    tokio_codec::{FramedRead, LinesCodec},
-    tokio_io::{AsyncRead, AsyncWrite},
-    NetworkBehaviour, PeerId, Swarm,
 };
+use std::{error::Error, task::{Context, Poll}};
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     env_logger::init();
 
     // Create a random key for ourselves.
@@ -49,17 +52,18 @@ fn main() {
     let local_peer_id = PeerId::from(local_key.public());
 
     // Set up a an encrypted DNS-enabled TCP Transport over the Mplex protocol.
-    let transport = build_development_transport(local_key);
+    let transport = build_development_transport(local_key)?;
 
     // We create a custom network behaviour that combines Kademlia and mDNS.
     #[derive(NetworkBehaviour)]
     struct MyBehaviour<TSubstream: AsyncRead + AsyncWrite> {
         kademlia: Kademlia<TSubstream, MemoryStore>,
-        mdns: Mdns<TSubstream>,
+        mdns: Mdns<TSubstream>
     }
 
-    impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<MdnsEvent>
+    impl<T> NetworkBehaviourEventProcess<MdnsEvent> for MyBehaviour<T>
-        for MyBehaviour<TSubstream>
+    where
+        T: AsyncRead + AsyncWrite
     {
         // Called when `mdns` produces an event.
         fn inject_event(&mut self, event: MdnsEvent) {
@@ -71,8 +75,9 @@ fn main() {
         }
     }
 
-    impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<KademliaEvent>
+    impl<T> NetworkBehaviourEventProcess<KademliaEvent> for MyBehaviour<T>
-        for MyBehaviour<TSubstream>
+    where
+        T: AsyncRead + AsyncWrite
     {
         // Called when `kademlia` produces an event.
         fn inject_event(&mut self, message: KademliaEvent) {
@@ -108,58 +113,50 @@ fn main() {
         // Create a Kademlia behaviour.
         let store = MemoryStore::new(local_peer_id.clone());
         let kademlia = Kademlia::new(local_peer_id.clone(), store);
-
+        let mdns = task::block_on(Mdns::new())?;
-        let behaviour = MyBehaviour {
+        let behaviour = MyBehaviour { kademlia, mdns };
-            kademlia,
-            mdns: Mdns::new().expect("Failed to create mDNS service"),
-        };
-
         Swarm::new(transport, behaviour, local_peer_id)
     };
 
-    // Read full lines from stdin.
+    // Read full lines from stdin
-    let stdin = tokio_stdin_stdout::stdin(0);
+    let mut stdin = io::BufReader::new(io::stdin()).lines();
-    let mut framed_stdin = FramedRead::new(stdin, LinesCodec::new());
 
     // Listen on all interfaces and whatever port the OS assigns.
-    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse().unwrap()).unwrap();
+    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse()?)?;
 
     // Kick it off.
     let mut listening = false;
-    tokio::run(futures::future::poll_fn(move || {
+    task::block_on(future::poll_fn(move |cx: &mut Context| {
         loop {
-            match framed_stdin.poll().expect("Error while polling stdin") {
+            match stdin.try_poll_next_unpin(cx)? {
-                Async::Ready(Some(line)) => {
+                Poll::Ready(Some(line)) => handle_input_line(&mut swarm.kademlia, line),
-                    handle_input_line(&mut swarm.kademlia, line);
+                Poll::Ready(None) => panic!("Stdin closed"),
+                Poll::Pending => break
             }
-                Async::Ready(None) => panic!("Stdin closed"),
-                Async::NotReady => break,
-            };
         }
-
         loop {
-            match swarm.poll().expect("Error while polling swarm") {
+            match swarm.poll_next_unpin(cx) {
-                Async::Ready(Some(_)) => {}
+                Poll::Ready(Some(event)) => println!("{:?}", event),
-                Async::Ready(None) | Async::NotReady => {
+                Poll::Ready(None) => return Poll::Ready(Ok(())),
+                Poll::Pending => {
                     if !listening {
                         if let Some(a) = Swarm::listeners(&swarm).next() {
                             println!("Listening on {:?}", a);
                             listening = true;
                         }
                     }
-                    break;
+                    break
                 }
             }
         }
+        Poll::Pending
+    }))
+}
 
-        Ok(Async::NotReady)
+fn handle_input_line<T>(kademlia: &mut Kademlia<T, MemoryStore>, line: String)
-    }));
+where
-}
+    T: AsyncRead + AsyncWrite
-
+{
-fn handle_input_line<TSubstream: AsyncRead + AsyncWrite>(
-    kademlia: &mut Kademlia<TSubstream, MemoryStore>,
-    line: String,
-) {
     let mut args = line.split(" ");
 
     match args.next() {

examples/ipfs-kad.rs

@@ -23,6 +23,7 @@
 //! You can pass as parameter a base58 peer ID to search for. If you don't pass any parameter, a
 //! peer ID will be generated randomly.
 
+use async_std::task;
 use futures::prelude::*;
 use libp2p::{
     Swarm,
@@ -32,10 +33,9 @@ use libp2p::{
 };
 use libp2p::kad::{Kademlia, KademliaConfig, KademliaEvent, GetClosestPeersError};
 use libp2p::kad::record::store::MemoryStore;
-use std::env;
+use std::{env, error::Error, time::Duration};
-use std::time::Duration;
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     env_logger::init();
 
     // Create a random key for ourselves.
@@ -43,7 +43,7 @@ fn main() {
     let local_peer_id = PeerId::from(local_key.public());
 
     // Set up a an encrypted DNS-enabled TCP Transport over the Mplex protocol
-    let transport = build_development_transport(local_key);
+    let transport = build_development_transport(local_key)?;
 
     // Create a swarm to manage peers and events.
     let mut swarm = {
@@ -60,7 +60,7 @@ fn main() {
         behaviour.add_address(&"QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt".parse().unwrap(), "/dnsaddr/bootstrap.libp2p.io".parse().unwrap());*/
 
         // The only address that currently works.
-        behaviour.add_address(&"QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ".parse().unwrap(), "/ip4/104.131.131.82/tcp/4001".parse().unwrap());
+        behaviour.add_address(&"QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ".parse()?, "/ip4/104.131.131.82/tcp/4001".parse()?);
 
         // The following addresses always fail signature verification, possibly due to
         // RSA keys with < 2048 bits.
@@ -80,7 +80,7 @@ fn main() {
 
     // Order Kademlia to search for a peer.
     let to_search: PeerId = if let Some(peer_id) = env::args().nth(1) {
-        peer_id.parse().expect("Failed to parse peer ID to find")
+        peer_id.parse()?
     } else {
         identity::Keypair::generate_ed25519().public().into()
     };
@@ -89,25 +89,21 @@ fn main() {
     swarm.get_closest_peers(to_search);
 
     // Kick it off!
-    tokio::run(futures::future::poll_fn(move || {
+    task::block_on(async move {
-        loop {
+        while let Some(event) = swarm.try_next().await? {
-            match swarm.poll().expect("Error while polling swarm") {
+            if let KademliaEvent::GetClosestPeersResult(result) = event {
-                Async::Ready(Some(KademliaEvent::GetClosestPeersResult(res))) => {
+                match result {
-                    match res {
+                    Ok(ok) =>
-                        Ok(ok) => {
                         if !ok.peers.is_empty() {
-                                println!("Query finished with closest peers: {:#?}", ok.peers);
+                            println!("Query finished with closest peers: {:#?}", ok.peers)
-                                return Ok(Async::Ready(()));
                         } else {
                             // The example is considered failed as there
                             // should always be at least 1 reachable peer.
-                                panic!("Query finished with no closest peers.");
+                            panic!("Query finished with no closest peers.")
                         }
-                        }
+                    Err(GetClosestPeersError::Timeout { peers, .. }) =>
-                        Err(GetClosestPeersError::Timeout { peers, .. }) => {
                         if !peers.is_empty() {
-                                println!("Query timed out with closest peers: {:#?}", peers);
+                            println!("Query timed out with closest peers: {:#?}", peers)
-                                return Ok(Async::Ready(()));
                         } else {
                             // The example is considered failed as there
                             // should always be at least 1 reachable peer.
@@ -115,12 +111,7 @@ fn main() {
                         }
                 }
             }
-                },
-                Async::Ready(Some(_)) => {},
-                Async::Ready(None) | Async::NotReady => break,
         }
-        }
+        Ok(())
-
+    })
-        Ok(Async::NotReady)
-    }));
 }

examples/mdns-passive-discovery.rs

@@ -18,26 +18,17 @@
 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-use futures::prelude::*;
+use async_std::task;
 use libp2p::mdns::service::{MdnsPacket, MdnsService};
-use std::io;
+use std::error::Error;
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
-    // This example provides passive discovery of the libp2p nodes on the network that send
+    // This example provides passive discovery of the libp2p nodes on the
-    // mDNS queries and answers.
+    // network that send mDNS queries and answers.
-
+    task::block_on(async move {
-    // We start by creating the service.
+        let mut service = MdnsService::new().await?;
-    let mut service = MdnsService::new().expect("Error while creating mDNS service");
-
-    // Create a never-ending `Future` that polls the service for events.
-    let future = futures::future::poll_fn(move || -> Poll<(), io::Error> {
         loop {
-            // Grab the next available packet from the service.
+            let (srv, packet) = service.next().await;
-            let packet = match service.poll() {
-                Async::Ready(packet) => packet,
-                Async::NotReady => return Ok(Async::NotReady),
-            };
-
             match packet {
                 MdnsPacket::Query(query) => {
                     // We detected a libp2p mDNS query on the network. In a real application, you
@@ -63,9 +54,7 @@ fn main() {
                     println!("Detected service query from {:?}", query.remote_addr());
                 }
             }
+            service = srv
         }
-    });
+    })
-
-    // Blocks the thread until the future runs to completion (which will never happen).
-    tokio::run(future.map_err(|err| panic!("{:?}", err)));
 }

examples/ping.rs

@@ -38,11 +38,12 @@
 //! The two nodes establish a connection, negotiate the ping protocol
 //! and begin pinging each other.
 
-use futures::{prelude::*, future};
+use async_std::task;
+use futures::{future, prelude::*};
 use libp2p::{identity, PeerId, ping::{Ping, PingConfig}, Swarm};
-use std::env;
+use std::{error::Error, task::{Context, Poll}};
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     env_logger::init();
 
     // Create a random PeerId.
@@ -51,7 +52,7 @@ fn main() {
     println!("Local peer id: {:?}", peer_id);
 
     // Create a transport.
-    let transport = libp2p::build_development_transport(id_keys);
+    let transport = libp2p::build_development_transport(id_keys)?;
 
     // Create a ping network behaviour.
     //
@@ -66,38 +67,33 @@ fn main() {
 
     // Dial the peer identified by the multi-address given as the second
     // command-line argument, if any.
-    if let Some(addr) = env::args().nth(1) {
+    if let Some(addr) = std::env::args().nth(1) {
-        let remote_addr = addr.clone();
+        let remote = addr.parse()?;
-        match addr.parse() {
+        Swarm::dial_addr(&mut swarm, remote)?;
-            Ok(remote) => {
+        println!("Dialed {}", addr)
-                match Swarm::dial_addr(&mut swarm, remote) {
-                    Ok(()) => println!("Dialed {:?}", remote_addr),
-                    Err(e) => println!("Dialing {:?} failed with: {:?}", remote_addr, e)
-                }
-            },
-            Err(err) => println!("Failed to parse address to dial: {:?}", err),
-        }
     }
 
     // Tell the swarm to listen on all interfaces and a random, OS-assigned port.
-    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse().unwrap()).unwrap();
+    Swarm::listen_on(&mut swarm, "/ip4/0.0.0.0/tcp/0".parse()?)?;
 
-    // Use tokio to drive the `Swarm`.
     let mut listening = false;
-    tokio::run(future::poll_fn(move || -> Result<_, ()> {
+    task::block_on(future::poll_fn(move |cx: &mut Context| {
         loop {
-            match swarm.poll().expect("Error while polling swarm") {
+            match swarm.poll_next_unpin(cx) {
-                Async::Ready(Some(e)) => println!("{:?}", e),
+                Poll::Ready(Some(event)) => println!("{:?}", event),
-                Async::Ready(None) | Async::NotReady => {
+                Poll::Ready(None) => return Poll::Ready(()),
+                Poll::Pending => {
                     if !listening {
-                        if let Some(a) = Swarm::listeners(&swarm).next() {
+                        for addr in Swarm::listeners(&swarm) {
-                            println!("Listening on {:?}", a);
+                            println!("Listening on {}", addr);
                             listening = true;
                         }
                     }
-                    return Ok(Async::NotReady)
+                    return Poll::Pending
                 }
             }
         }
     }));
+
+    Ok(())
 }

misc/core-derive/Cargo.toml

@@ -13,8 +13,8 @@ categories = ["network-programming", "asynchronous"]
 proc-macro = true
 
 [dependencies]
-syn = { version = "0.15.22", default-features = false, features = ["clone-impls", "derive", "parsing", "printing", "proc-macro"] }
+syn = { version = "1.0.8", default-features = false, features = ["clone-impls", "derive", "parsing", "printing", "proc-macro"] }
-quote = "0.6"
+quote = "1.0"
 
 [dev-dependencies]
 libp2p = { version = "0.13.0", path = "../.." }

misc/core-derive/src/lib.rs

@@ -96,8 +96,9 @@ fn build_struct(ast: &DeriveInput, data_struct: &DataStruct) -> TokenStream {
             })
             .collect::<Vec<_>>();
 
-        additional.push(quote!{#substream_generic: ::libp2p::tokio_io::AsyncRead});
+        additional.push(quote!{#substream_generic: ::libp2p::futures::io::AsyncRead});
-        additional.push(quote!{#substream_generic: ::libp2p::tokio_io::AsyncWrite});
+        additional.push(quote!{#substream_generic: ::libp2p::futures::io::AsyncWrite});
+        additional.push(quote!{#substream_generic: Unpin});
 
         if let Some(where_clause) = where_clause {
             if where_clause.predicates.trailing_punct() {
@@ -118,7 +119,7 @@ fn build_struct(ast: &DeriveInput, data_struct: &DataStruct) -> TokenStream {
         for meta_items in ast.attrs.iter().filter_map(get_meta_items) {
             for meta_item in meta_items {
                 match meta_item {
-                    syn::NestedMeta::Meta(syn::Meta::NameValue(ref m)) if m.ident == "out_event" => {
+                    syn::NestedMeta::Meta(syn::Meta::NameValue(ref m)) if m.path.is_ident("out_event") => {
                         if let syn::Lit::Str(ref s) = m.lit {
                             let ident: syn::Type = syn::parse_str(&s.value()).unwrap();
                             out = quote!{#ident};
@@ -381,11 +382,11 @@ fn build_struct(ast: &DeriveInput, data_struct: &DataStruct) -> TokenStream {
     // If we find a `#[behaviour(poll_method = "poll")]` attribute on the struct, we call
     // `self.poll()` at the end of the polling.
     let poll_method = {
-        let mut poll_method = quote!{Poll::Pending};
+        let mut poll_method = quote!{std::task::Poll::Pending};
         for meta_items in ast.attrs.iter().filter_map(get_meta_items) {
             for meta_item in meta_items {
                 match meta_item {
-                    syn::NestedMeta::Meta(syn::Meta::NameValue(ref m)) if m.ident == "poll_method" => {
+                    syn::NestedMeta::Meta(syn::Meta::NameValue(ref m)) if m.path.is_ident("poll_method") => {
                         if let syn::Lit::Str(ref s) = m.lit {
                             let ident: Ident = syn::parse_str(&s.value()).unwrap();
                             poll_method = quote!{#name::#ident(self)};
@@ -418,26 +419,26 @@ fn build_struct(ast: &DeriveInput, data_struct: &DataStruct) -> TokenStream {
 
         Some(quote!{
             loop {
-                match #field_name.poll(poll_params) {
+                match #field_name.poll(cx, poll_params) {
-                    Poll::Ready(#network_behaviour_action::GenerateEvent(event)) => {
+                    std::task::Poll::Ready(#network_behaviour_action::GenerateEvent(event)) => {
                         #net_behv_event_proc::inject_event(self, event)
                     }
-                    Poll::Ready(#network_behaviour_action::DialAddress { address }) => {
+                    std::task::Poll::Ready(#network_behaviour_action::DialAddress { address }) => {
-                        return Poll::Ready(#network_behaviour_action::DialAddress { address });
+                        return std::task::Poll::Ready(#network_behaviour_action::DialAddress { address });
                     }
-                    Poll::Ready(#network_behaviour_action::DialPeer { peer_id }) => {
+                    std::task::Poll::Ready(#network_behaviour_action::DialPeer { peer_id }) => {
-                        return Poll::Ready(#network_behaviour_action::DialPeer { peer_id });
+                        return std::task::Poll::Ready(#network_behaviour_action::DialPeer { peer_id });
                     }
-                    Poll::Ready(#network_behaviour_action::SendEvent { peer_id, event }) => {
+                    std::task::Poll::Ready(#network_behaviour_action::SendEvent { peer_id, event }) => {
-                        return Poll::Ready(#network_behaviour_action::SendEvent {
+                        return std::task::Poll::Ready(#network_behaviour_action::SendEvent {
                             peer_id,
                             event: #wrapped_event,
                         });
                     }
-                    Poll::Ready(#network_behaviour_action::ReportObservedAddr { address }) => {
+                    std::task::Poll::Ready(#network_behaviour_action::ReportObservedAddr { address }) => {
-                        return Poll::Ready(#network_behaviour_action::ReportObservedAddr { address });
+                        return std::task::Poll::Ready(#network_behaviour_action::ReportObservedAddr { address });
                     }
-                    Poll::Pending => break,
+                    std::task::Poll::Pending => break,
                 }
             }
         })
@@ -526,9 +527,11 @@ fn build_struct(ast: &DeriveInput, data_struct: &DataStruct) -> TokenStream {
 
 fn get_meta_items(attr: &syn::Attribute) -> Option<Vec<syn::NestedMeta>> {
     if attr.path.segments.len() == 1 && attr.path.segments[0].ident == "behaviour" {
-        match attr.interpret_meta() {
+        match attr.parse_meta() {
-            Some(syn::Meta::List(ref meta)) => Some(meta.nested.iter().cloned().collect()),
+            Ok(syn::Meta::List(ref meta)) => Some(meta.nested.iter().cloned().collect()),
-            _ => {
+            Ok(_) => None,
+            Err(e) => {
+                eprintln!("error parsing attribute metadata: {}", e);
                 None
             }
         }
@@ -542,7 +545,7 @@ fn is_ignored(field: &syn::Field) -> bool {
     for meta_items in field.attrs.iter().filter_map(get_meta_items) {
         for meta_item in meta_items {
             match meta_item {
-                syn::NestedMeta::Meta(syn::Meta::Word(ref m)) if m == "ignore" => {
+                syn::NestedMeta::Meta(syn::Meta::Path(ref m)) if m.is_ident("ignore") => {
                     return true;
                 }
                 _ => ()

misc/core-derive/tests/test.rs

@@ -46,7 +46,7 @@ fn one_field() {
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }
@@ -71,7 +71,7 @@ fn two_fields() {
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }
@@ -104,7 +104,7 @@ fn three_fields() {
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }
@@ -130,11 +130,11 @@ fn custom_polling() {
     }
 
     impl<TSubstream> Foo<TSubstream> {
-        fn foo<T>(&mut self) -> libp2p::futures::Async<libp2p::swarm::NetworkBehaviourAction<T, ()>> { libp2p::futures::Async::NotReady }
+        fn foo<T>(&mut self) -> std::task::Poll<libp2p::swarm::NetworkBehaviourAction<T, ()>> { std::task::Poll::Pending }
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }
@@ -160,7 +160,7 @@ fn custom_event_no_polling() {
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }
@@ -186,11 +186,11 @@ fn custom_event_and_polling() {
     }
 
     impl<TSubstream> Foo<TSubstream> {
-        fn foo<T>(&mut self) -> libp2p::futures::Async<libp2p::swarm::NetworkBehaviourAction<T, String>> { libp2p::futures::Async::NotReady }
+        fn foo<T>(&mut self) -> std::task::Poll<libp2p::swarm::NetworkBehaviourAction<T, String>> { std::task::Poll::Pending }
     }
 
     #[allow(dead_code)]
-    fn foo<TSubstream: libp2p::tokio_io::AsyncRead + libp2p::tokio_io::AsyncWrite>() {
+    fn foo<TSubstream: libp2p::futures::AsyncRead + libp2p::futures::AsyncWrite + Send + Unpin + 'static>() {
         require_net_behaviour::<Foo<TSubstream>>();
     }
 }

protocols/ping/src/handler.rs

@@ -185,7 +185,7 @@ impl<TSubstream> PingHandler<TSubstream> {
 
 impl<TSubstream> ProtocolsHandler for PingHandler<TSubstream>
 where
-    TSubstream: AsyncRead + AsyncWrite + Unpin + 'static,
+    TSubstream: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {
     type InEvent = Void;
     type OutEvent = PingResult;

protocols/ping/src/lib.rs

@@ -93,7 +93,7 @@ impl<TSubstream> Default for Ping<TSubstream> {
 
 impl<TSubstream> NetworkBehaviour for Ping<TSubstream>
 where
-    TSubstream: AsyncRead + AsyncWrite + Unpin + 'static,
+    TSubstream: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {
     type ProtocolsHandler = PingHandler<TSubstream>;
     type OutEvent = PingEvent;

protocols/ping/src/protocol.rs

@@ -18,11 +18,11 @@
 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-use futures::prelude::*;
+use futures::{future::BoxFuture, prelude::*};
 use libp2p_core::{InboundUpgrade, OutboundUpgrade, UpgradeInfo, Negotiated};
 use log::debug;
 use rand::{distributions, prelude::*};
-use std::{io, iter, pin::Pin, time::Duration};
+use std::{io, iter, time::Duration};
 use wasm_timer::Instant;
 
 /// Represents a prototype for an upgrade to handle the ping protocol.
@@ -55,36 +55,35 @@ impl UpgradeInfo for Ping {
 
 impl<TSocket> InboundUpgrade<TSocket> for Ping
 where
-    TSocket: AsyncRead + AsyncWrite + Unpin + 'static,
+    TSocket: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {
     type Output = ();
     type Error = io::Error;
-    type Future = Pin<Box<dyn Future<Output = Result<(), io::Error>>>>;
+    type Future = BoxFuture<'static, Result<(), io::Error>>;
 
     fn upgrade_inbound(self, mut socket: Negotiated<TSocket>, _: Self::Info) -> Self::Future {
-        Box::pin(async move {
+        async move {
             let mut payload = [0u8; 32];
             socket.read_exact(&mut payload).await?;
             socket.write_all(&payload).await?;
             socket.close().await?;
             Ok(())
-        })
+        }.boxed()
     }
 }
 
 impl<TSocket> OutboundUpgrade<TSocket> for Ping
 where
-    TSocket: AsyncRead + AsyncWrite + Unpin + 'static,
+    TSocket: AsyncRead + AsyncWrite + Send + Unpin + 'static,
 {
     type Output = Duration;
     type Error = io::Error;
-    type Future = Pin<Box<dyn Future<Output = Result<Duration, io::Error>>>>;
+    type Future = BoxFuture<'static, Result<Duration, io::Error>>;
 
     fn upgrade_outbound(self, mut socket: Negotiated<TSocket>, _: Self::Info) -> Self::Future {
         let payload: [u8; 32] = thread_rng().sample(distributions::Standard);
         debug!("Preparing ping payload {:?}", payload);
-
+        async move {
-        Box::pin(async move {
             socket.write_all(&payload).await?;
             socket.close().await?;
             let started = Instant::now();
@@ -96,7 +95,7 @@ where
             } else {
                 Err(io::Error::new(io::ErrorKind::InvalidData, "Ping payload mismatch"))
             }
-        })
+        }.boxed()
     }
 }