Use event_process = false for Bob

As we do not process the event, we can just implement the needed `From`
traits.

swap/src/protocol/bob.rs

@@ -12,7 +12,7 @@ use crate::{
     protocol::{alice, alice::TransferProof, bob, SwapAmounts},
     seed::Seed,
 };
-use anyhow::{bail, Result};
+use anyhow::{bail, Error, Result};
 use libp2p::{core::Multiaddr, identity::Keypair, NetworkBehaviour, PeerId};
 use rand::rngs::OsRng;
 use std::{path::PathBuf, sync::Arc};
@@ -27,6 +27,7 @@ pub use self::{
     swap_request::*,
 };
 pub use execution_setup::{Message0, Message2, Message4};
+use libp2p::request_response::ResponseChannel;
 
 mod encrypted_signature;
 pub mod event_loop;
@@ -206,8 +207,13 @@ pub enum OutEvent {
     ConnectionEstablished(PeerId),
     SwapResponse(alice::SwapResponse),
     ExecutionSetupDone(Result<Box<State2>>),
-    TransferProof(Box<TransferProof>),
+    TransferProof {
+        msg: Box<TransferProof>,
+        channel: ResponseChannel<()>,
+    },
     EncryptedSignatureAcknowledged,
+    ResponseSent, // Same variant is used for all messages as no processing is done
+    Failure(Error),
 }
 
 impl From<peer_tracker::OutEvent> for OutEvent {
@@ -222,7 +228,11 @@ impl From<peer_tracker::OutEvent> for OutEvent {
 
 impl From<swap_request::OutEvent> for OutEvent {
     fn from(event: swap_request::OutEvent) -> Self {
-        OutEvent::SwapResponse(event.swap_response)
+        use swap_request::OutEvent::*;
+        match event {
+            MsgReceived(swap_response) => OutEvent::SwapResponse(swap_response),
+            Failure(err) => OutEvent::Failure(err.context("Failre with Swap Request")),
+        }
     }
 }
 
@@ -236,16 +246,24 @@ impl From<execution_setup::OutEvent> for OutEvent {
 
 impl From<transfer_proof::OutEvent> for OutEvent {
     fn from(event: transfer_proof::OutEvent) -> Self {
+        use transfer_proof::OutEvent::*;
         match event {
-            transfer_proof::OutEvent::Msg(msg) => OutEvent::TransferProof(Box::new(msg)),
+            MsgReceived { msg, channel } => OutEvent::TransferProof {
+                msg: Box::new(msg),
+                channel,
+            },
+            AckSent => OutEvent::ResponseSent,
+            Failure(err) => OutEvent::Failure(err.context("Failure with Transfer Proof")),
         }
     }
 }
 
 impl From<encrypted_signature::OutEvent> for OutEvent {
     fn from(event: encrypted_signature::OutEvent) -> Self {
+        use encrypted_signature::OutEvent::*;
         match event {
-            encrypted_signature::OutEvent::Acknowledged => OutEvent::EncryptedSignatureAcknowledged,
+            Acknowledged => OutEvent::EncryptedSignatureAcknowledged,
+            Failure(err) => OutEvent::Failure(err.context("Failure with Encrypted Signature")),
         }
     }
 }

swap/src/protocol/bob/encrypted_signature.rs

@@ -1,61 +1,38 @@
 use crate::network::request_response::{CborCodec, EncryptedSignatureProtocol, TIMEOUT};
+use anyhow::{anyhow, Error};
 use libp2p::{
     request_response::{
-        handler::RequestProtocol, ProtocolSupport, RequestResponse, RequestResponseConfig,
-        RequestResponseEvent, RequestResponseMessage,
+        ProtocolSupport, RequestResponse, RequestResponseConfig, RequestResponseEvent,
+        RequestResponseMessage,
     },
-    swarm::{NetworkBehaviourAction, NetworkBehaviourEventProcess, PollParameters},
     NetworkBehaviour, PeerId,
 };
 use serde::{Deserialize, Serialize};
-use std::{
-    collections::VecDeque,
-    task::{Context, Poll},
-    time::Duration,
-};
-use tracing::error;
+use std::time::Duration;
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct EncryptedSignature {
     pub tx_redeem_encsig: crate::bitcoin::EncryptedSignature,
 }
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug)]
 pub enum OutEvent {
     Acknowledged,
+    Failure(Error),
 }
 
 /// A `NetworkBehaviour` that represents sending encrypted signature to Alice.
 #[derive(NetworkBehaviour)]
-#[behaviour(out_event = "OutEvent", poll_method = "poll")]
+#[behaviour(out_event = "OutEvent", event_process = false)]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
     rr: RequestResponse<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
-    #[behaviour(ignore)]
-    events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
     pub fn send(&mut self, alice: PeerId, msg: EncryptedSignature) {
         let _id = self.rr.send_request(&alice, msg);
     }
-
-    fn poll(
-        &mut self,
-        _: &mut Context<'_>,
-        _: &mut impl PollParameters,
-    ) -> Poll<
-        NetworkBehaviourAction<
-            RequestProtocol<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
-            OutEvent,
-        >,
-    > {
-        if let Some(event) = self.events.pop_front() {
-            return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
-        }
-
-        Poll::Pending
-    }
 }
 
 impl Default for Behaviour {
@@ -70,33 +47,30 @@ impl Default for Behaviour {
                 vec![(EncryptedSignatureProtocol, ProtocolSupport::Outbound)],
                 config,
             ),
-            events: Default::default(),
         }
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<EncryptedSignature, ()>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<EncryptedSignature, ()>) {
+impl From<RequestResponseEvent<EncryptedSignature, ()>> for OutEvent {
+    fn from(event: RequestResponseEvent<EncryptedSignature, ()>) -> Self {
         match event {
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Request { .. },
                 ..
-            } => panic!("Bob should never get a request from Alice"),
+            } => OutEvent::Failure(anyhow!("Bob should never get a request from Alice")),
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Response { .. },
                 ..
-            } => {
-                self.events.push_back(OutEvent::Acknowledged);
-            }
+            } => OutEvent::Acknowledged,
             RequestResponseEvent::InboundFailure { error, .. } => {
-                error!("Inbound failure: {:?}", error);
+                OutEvent::Failure(anyhow!("Inbound failure: {:?}", error))
             }
             RequestResponseEvent::OutboundFailure { error, .. } => {
-                error!("Outbound failure: {:?}", error);
-            }
-            RequestResponseEvent::ResponseSent { .. } => {
-                unreachable!("Bob does not send the encrypted signature response to Alice");
+                OutEvent::Failure(anyhow!("Outbound failure: {:?}", error))
             }
+            RequestResponseEvent::ResponseSent { .. } => OutEvent::Failure(anyhow!(
+                "Bob does not send the encrypted signature response to Alice"
+            )),
         }
     }
 }

swap/src/protocol/bob/event_loop.rs

@@ -190,13 +190,21 @@ impl EventLoop {
                         OutEvent::ExecutionSetupDone(res) => {
                             let _ = self.done_execution_setup.send(res.map(|state|*state)).await;
                         }
-                        OutEvent::TransferProof(msg) => {
+                        OutEvent::TransferProof{ msg, channel }=> {
                             let _ = self.recv_transfer_proof.send(*msg).await;
+                            // Send back empty response so that the request/response protocol completes.
+                            if let Err(error) = self.swarm.transfer_proof.send_ack(channel) {
+                                error!("Failed to send Transfer Proof ack: {:?}", error);
+                            }
                         }
                         OutEvent::EncryptedSignatureAcknowledged => {
                             debug!("Alice acknowledged encrypted signature");
                             let _ = self.recv_encrypted_signature_ack.send(()).await;
                         }
+                        OutEvent::ResponseSent => {}
+                        OutEvent::Failure(err) => {
+                            error!("Communication error: {:#}", err)
+                        }
                     }
                 },
                 option = self.dial_alice.recv().fuse() => {

swap/src/protocol/bob/swap_request.rs

@@ -2,22 +2,17 @@ use crate::{
     network::request_response::{CborCodec, Swap, TIMEOUT},
     protocol::alice::SwapResponse,
 };
-use anyhow::Result;
+use anyhow::{anyhow, Error, Result};
 use libp2p::{
     request_response::{
-        handler::RequestProtocol, ProtocolSupport, RequestId, RequestResponse,
-        RequestResponseConfig, RequestResponseEvent, RequestResponseMessage,
+        ProtocolSupport, RequestId, RequestResponse, RequestResponseConfig, RequestResponseEvent,
+        RequestResponseMessage,
     },
-    swarm::{NetworkBehaviourAction, NetworkBehaviourEventProcess, PollParameters},
     NetworkBehaviour, PeerId,
 };
 use serde::{Deserialize, Serialize};
-use std::{
-    collections::VecDeque,
-    task::{Context, Poll},
-    time::Duration,
-};
-use tracing::{debug, error};
+use std::time::Duration;
+use tracing::debug;
 
 #[derive(Clone, Copy, Debug, Serialize, Deserialize)]
 pub struct SwapRequest {
@@ -25,19 +20,18 @@ pub struct SwapRequest {
     pub btc_amount: bitcoin::Amount,
 }
 
-#[derive(Copy, Clone, Debug)]
-pub struct OutEvent {
-    pub swap_response: SwapResponse,
+#[derive(Debug)]
+pub enum OutEvent {
+    MsgReceived(SwapResponse),
+    Failure(Error),
 }
 
 /// A `NetworkBehaviour` that represents doing the negotiation of a swap.
 #[derive(NetworkBehaviour)]
-#[behaviour(out_event = "OutEvent", poll_method = "poll")]
+#[behaviour(out_event = "OutEvent", event_process = false)]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
     rr: RequestResponse<CborCodec<Swap, SwapRequest, SwapResponse>>,
-    #[behaviour(ignore)]
-    events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
@@ -46,23 +40,6 @@ impl Behaviour {
 
         Ok(id)
     }
-
-    fn poll(
-        &mut self,
-        _: &mut Context<'_>,
-        _: &mut impl PollParameters,
-    ) -> Poll<
-        NetworkBehaviourAction<
-            RequestProtocol<CborCodec<Swap, SwapRequest, SwapResponse>>,
-            OutEvent,
-        >,
-    > {
-        if let Some(event) = self.events.pop_front() {
-            return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
-        }
-
-        Poll::Pending
-    }
 }
 
 impl Default for Behaviour {
@@ -78,35 +55,33 @@ impl Default for Behaviour {
                 vec![(Swap, ProtocolSupport::Outbound)],
                 config,
             ),
-            events: Default::default(),
         }
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<SwapRequest, SwapResponse>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<SwapRequest, SwapResponse>) {
+impl From<RequestResponseEvent<SwapRequest, SwapResponse>> for OutEvent {
+    fn from(event: RequestResponseEvent<SwapRequest, SwapResponse>) -> Self {
         match event {
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Request { .. },
                 ..
-            } => panic!("Bob should never get a request from Alice"),
+            } => OutEvent::Failure(anyhow!("Bob should never get a request from Alice")),
             RequestResponseEvent::Message {
+                peer,
                 message: RequestResponseMessage::Response { response, .. },
                 ..
             } => {
-                debug!("Received swap response");
-                self.events.push_back(OutEvent {
-                    swap_response: response,
-                });
+                debug!("Received swap response from {}", peer);
+                OutEvent::MsgReceived(response)
             }
             RequestResponseEvent::InboundFailure { error, .. } => {
-                error!("Inbound failure: {:?}", error);
+                OutEvent::Failure(anyhow!("Inbound failure: {:?}", error))
             }
             RequestResponseEvent::OutboundFailure { error, .. } => {
-                error!("Outbound failure: {:?}", error);
+                OutEvent::Failure(anyhow!("Outbound failure: {:?}", error))
             }
             RequestResponseEvent::ResponseSent { .. } => {
-                error!("Bob does not send a swap response to Alice");
+                OutEvent::Failure(anyhow!("Bob does not send a swap response to Alice"))
             }
         }
     }

swap/src/protocol/bob/transfer_proof.rs

@@ -2,53 +2,41 @@ use crate::{
     network::request_response::{CborCodec, TransferProofProtocol, TIMEOUT},
     protocol::alice::TransferProof,
 };
+use anyhow::{anyhow, Error, Result};
 use libp2p::{
     request_response::{
-        handler::RequestProtocol, ProtocolSupport, RequestResponse, RequestResponseConfig,
-        RequestResponseEvent, RequestResponseMessage,
+        ProtocolSupport, RequestResponse, RequestResponseConfig, RequestResponseEvent,
+        RequestResponseMessage, ResponseChannel,
     },
-    swarm::{NetworkBehaviourAction, NetworkBehaviourEventProcess, PollParameters},
     NetworkBehaviour,
 };
-use std::{
-    collections::VecDeque,
-    task::{Context, Poll},
-    time::Duration,
-};
-use tracing::{debug, error};
+use std::time::Duration;
+use tracing::debug;
 
 #[derive(Debug)]
 pub enum OutEvent {
-    Msg(TransferProof),
+    MsgReceived {
+        msg: TransferProof,
+        channel: ResponseChannel<()>,
+    },
+    AckSent,
+    Failure(Error),
 }
 
 /// A `NetworkBehaviour` that represents receiving the transfer proof from
 /// Alice.
 #[derive(NetworkBehaviour)]
-#[behaviour(out_event = "OutEvent", poll_method = "poll")]
+#[behaviour(out_event = "OutEvent", event_process = false)]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
     rr: RequestResponse<CborCodec<TransferProofProtocol, TransferProof, ()>>,
-    #[behaviour(ignore)]
-    events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
-    fn poll(
-        &mut self,
-        _: &mut Context<'_>,
-        _: &mut impl PollParameters,
-    ) -> Poll<
-        NetworkBehaviourAction<
-            RequestProtocol<CborCodec<TransferProofProtocol, TransferProof, ()>>,
-            OutEvent,
-        >,
-    > {
-        if let Some(event) = self.events.pop_front() {
-            return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
-        }
-
-        Poll::Pending
+    pub fn send_ack(&mut self, channel: ResponseChannel<()>) -> Result<()> {
+        self.rr
+            .send_response(channel, ())
+            .map_err(|err| anyhow!("Failed to ack transfer proof: {:?}", err))
     }
 }
 
@@ -64,40 +52,38 @@ impl Default for Behaviour {
                 vec![(TransferProofProtocol, ProtocolSupport::Inbound)],
                 config,
             ),
-            events: Default::default(),
         }
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<TransferProof, ()>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<TransferProof, ()>) {
+impl From<RequestResponseEvent<TransferProof, ()>> for OutEvent {
+    fn from(event: RequestResponseEvent<TransferProof, ()>) -> Self {
         match event {
             RequestResponseEvent::Message {
+                peer,
                 message:
                     RequestResponseMessage::Request {
                         request, channel, ..
                     },
                 ..
             } => {
-                debug!("Received Transfer Proof");
-                self.events.push_back(OutEvent::Msg(request));
-                // Send back empty response so that the request/response protocol completes.
-                let _ = self
-                    .rr
-                    .send_response(channel, ())
-                    .map_err(|err| error!("Failed to send message 3: {:?}", err));
+                debug!("Received Transfer Proof from {}", peer);
+                OutEvent::MsgReceived {
+                    msg: request,
+                    channel,
+                }
             }
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Response { .. },
                 ..
-            } => panic!("Bob should not get a Response"),
+            } => OutEvent::Failure(anyhow!("Bob should not get a Response")),
             RequestResponseEvent::InboundFailure { error, .. } => {
-                error!("Inbound failure: {:?}", error);
+                OutEvent::Failure(anyhow!("Inbound failure: {:?}", error))
             }
             RequestResponseEvent::OutboundFailure { error, .. } => {
-                error!("Outbound failure: {:?}", error);
+                OutEvent::Failure(anyhow!("Outbound failure: {:?}", error))
             }
-            RequestResponseEvent::ResponseSent { .. } => debug!("Bob ack'd transfer proof message"),
+            RequestResponseEvent::ResponseSent { .. } => OutEvent::AckSent,
         }
     }
 }