From 554ae6c00e16ca8e4db6689d5376b5fcee88fc75 Mon Sep 17 00:00:00 2001
From: Franck Royer <franck@coblox.tech>
Date: Fri, 5 Feb 2021 13:48:24 +1100
Subject: [PATCH] Remove Request Response types

These are actually not needed and forces us to cater for variants when
processing requests and responses.
---
 swap/src/network/request_response.rs          | 48 ++++++++-----------
 swap/src/protocol/alice.rs                    |  3 +-
 .../src/protocol/alice/encrypted_signature.rs | 28 +++++------
 swap/src/protocol/alice/event_loop.rs         |  8 ++--
 swap/src/protocol/alice/swap_response.rs      | 38 +++++++++------
 swap/src/protocol/alice/transfer_proof.rs     | 23 ++++-----
 swap/src/protocol/bob/encrypted_signature.rs  | 22 ++++-----
 swap/src/protocol/bob/swap_request.rs         | 28 ++++++-----
 swap/src/protocol/bob/transfer_proof.rs       | 32 +++++++------
 9 files changed, 116 insertions(+), 114 deletions(-)

diff --git a/swap/src/network/request_response.rs b/swap/src/network/request_response.rs
index ab721f84..9a7ac4dd 100644
--- a/swap/src/network/request_response.rs
+++ b/swap/src/network/request_response.rs
@@ -1,14 +1,10 @@
-use crate::protocol::{
-    alice::{SwapResponse, TransferProof},
-    bob::{EncryptedSignature, SwapRequest},
-};
 use async_trait::async_trait;
 use futures::prelude::*;
 use libp2p::{
     core::{upgrade, upgrade::ReadOneError},
     request_response::{ProtocolName, RequestResponseCodec},
 };
-use serde::{Deserialize, Serialize};
+use serde::{de::DeserializeOwned, Serialize};
 use std::{fmt::Debug, io, marker::PhantomData};
 
 /// Time to wait for a response back once we send a request.
@@ -17,20 +13,6 @@ pub const TIMEOUT: u64 = 3600; // One hour.
 /// Message receive buffer.
 pub const BUF_SIZE: usize = 1024 * 1024;
 
-#[derive(Clone, Debug, Serialize, Deserialize)]
-pub enum Request {
-    SwapRequest(Box<SwapRequest>),
-    TransferProof(Box<TransferProof>),
-    EncryptedSignature(Box<EncryptedSignature>),
-}
-
-#[derive(Clone, Debug, Serialize, Deserialize)]
-pub enum Response {
-    SwapResponse(Box<SwapResponse>),
-    TransferProof,
-    EncryptedSignature,
-}
-
 #[derive(Debug, Clone, Copy, Default)]
 pub struct Swap;
 
@@ -58,19 +40,29 @@ impl ProtocolName for EncryptedSignatureProtocol {
     }
 }
 
-#[derive(Clone, Copy, Debug, Default)]
-pub struct CborCodec<P> {
-    phantom: PhantomData<P>,
+#[derive(Clone, Copy, Debug)]
+pub struct CborCodec<P, Req, Res> {
+    phantom: PhantomData<(P, Req, Res)>,
+}
+
+impl<P, Req, Res> Default for CborCodec<P, Req, Res> {
+    fn default() -> Self {
+        Self {
+            phantom: PhantomData::default(),
+        }
+    }
 }
 
 #[async_trait]
-impl<P> RequestResponseCodec for CborCodec<P>
+impl<P, Req, Res> RequestResponseCodec for CborCodec<P, Req, Res>
 where
-    P: Send + Sync + Clone + ProtocolName,
+    P: ProtocolName + Send + Sync + Clone,
+    Req: DeserializeOwned + Serialize + Send,
+    Res: DeserializeOwned + Serialize + Send,
 {
     type Protocol = P;
-    type Request = Request;
-    type Response = Response;
+    type Request = Req;
+    type Response = Res;
 
     async fn read_request<T>(&mut self, _: &Self::Protocol, io: &mut T) -> io::Result<Self::Request>
     where
@@ -81,7 +73,7 @@ where
             e => io::Error::new(io::ErrorKind::Other, e),
         })?;
         let mut de = serde_cbor::Deserializer::from_slice(&message);
-        let msg = Request::deserialize(&mut de).map_err(|e| {
+        let msg = Req::deserialize(&mut de).map_err(|e| {
             tracing::debug!("serde read_request error: {:?}", e);
             io::Error::new(io::ErrorKind::Other, e)
         })?;
@@ -101,7 +93,7 @@ where
             .await
             .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
         let mut de = serde_cbor::Deserializer::from_slice(&message);
-        let msg = Response::deserialize(&mut de).map_err(|e| {
+        let msg = Res::deserialize(&mut de).map_err(|e| {
             tracing::debug!("serde read_response error: {:?}", e);
             io::Error::new(io::ErrorKind::InvalidData, e)
         })?;
diff --git a/swap/src/protocol/alice.rs b/swap/src/protocol/alice.rs
index dffafc85..392bacfa 100644
--- a/swap/src/protocol/alice.rs
+++ b/swap/src/protocol/alice.rs
@@ -30,7 +30,6 @@ pub use self::{
     swap_response::*,
     transfer_proof::TransferProof,
 };
-use crate::network::request_response::Response;
 pub use execution_setup::Message3;
 
 mod encrypted_signature;
@@ -280,7 +279,7 @@ impl Behaviour {
     /// Alice always sends her messages as a response to a request from Bob.
     pub fn send_swap_response(
         &mut self,
-        channel: ResponseChannel<Response>,
+        channel: ResponseChannel<SwapResponse>,
         swap_response: SwapResponse,
     ) -> Result<()> {
         self.amounts.send(channel, swap_response)?;
diff --git a/swap/src/protocol/alice/encrypted_signature.rs b/swap/src/protocol/alice/encrypted_signature.rs
index 1c7cf0eb..40192f2a 100644
--- a/swap/src/protocol/alice/encrypted_signature.rs
+++ b/swap/src/protocol/alice/encrypted_signature.rs
@@ -1,7 +1,5 @@
 use crate::{
-    network::request_response::{
-        CborCodec, EncryptedSignatureProtocol, Request, Response, TIMEOUT,
-    },
+    network::request_response::{CborCodec, EncryptedSignatureProtocol, TIMEOUT},
     protocol::bob::EncryptedSignature,
 };
 use libp2p::{
@@ -30,7 +28,7 @@ pub enum OutEvent {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<EncryptedSignatureProtocol>>,
+    rr: RequestResponse<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
@@ -41,7 +39,10 @@ impl Behaviour {
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
     ) -> Poll<
-        NetworkBehaviourAction<RequestProtocol<CborCodec<EncryptedSignatureProtocol>>, OutEvent>,
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
+            OutEvent,
+        >,
     > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
@@ -68,8 +69,8 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<EncryptedSignature, ()>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<EncryptedSignature, ()>) {
         match event {
             RequestResponseEvent::Message {
                 message:
@@ -78,14 +79,11 @@ impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for B
                     },
                 ..
             } => {
-                if let Request::EncryptedSignature(msg) = request {
-                    debug!("Received encrypted signature");
-                    self.events.push_back(OutEvent::Msg(*msg));
-                    // Send back empty response so that the request/response protocol completes.
-                    if let Err(error) = self.rr.send_response(channel, Response::EncryptedSignature)
-                    {
-                        error!("Failed to send Encrypted Signature ack: {:?}", error);
-                    }
+                debug!("Received encrypted signature");
+                self.events.push_back(OutEvent::Msg(request));
+                // Send back empty response so that the request/response protocol completes.
+                if let Err(error) = self.rr.send_response(channel, ()) {
+                    error!("Failed to send Encrypted Signature ack: {:?}", error);
                 }
             }
             RequestResponseEvent::Message {
diff --git a/swap/src/protocol/alice/event_loop.rs b/swap/src/protocol/alice/event_loop.rs
index 01af9288..1ee99764 100644
--- a/swap/src/protocol/alice/event_loop.rs
+++ b/swap/src/protocol/alice/event_loop.rs
@@ -1,5 +1,5 @@
 use crate::{
-    network::{request_response::Response, transport::SwapTransport, TokioExecutor},
+    network::{transport::SwapTransport, TokioExecutor},
     protocol::{
         alice::{Behaviour, OutEvent, State0, State3, SwapResponse, TransferProof},
         bob::EncryptedSignature,
@@ -37,7 +37,7 @@ pub struct EventLoopHandle {
     recv_encrypted_signature: Receiver<EncryptedSignature>,
     request: Receiver<crate::protocol::alice::swap_response::OutEvent>,
     conn_established: Receiver<PeerId>,
-    send_swap_response: Sender<(ResponseChannel<Response>, SwapResponse)>,
+    send_swap_response: Sender<(ResponseChannel<SwapResponse>, SwapResponse)>,
     start_execution_setup: Sender<(PeerId, State0)>,
     send_transfer_proof: Sender<(PeerId, TransferProof)>,
     recv_transfer_proof_ack: Receiver<()>,
@@ -81,7 +81,7 @@ impl EventLoopHandle {
 
     pub async fn send_swap_response(
         &mut self,
-        channel: ResponseChannel<Response>,
+        channel: ResponseChannel<SwapResponse>,
         swap_response: SwapResponse,
     ) -> Result<()> {
         let _ = self
@@ -110,7 +110,7 @@ pub struct EventLoop {
     recv_encrypted_signature: Sender<EncryptedSignature>,
     request: Sender<crate::protocol::alice::swap_response::OutEvent>,
     conn_established: Sender<PeerId>,
-    send_swap_response: Receiver<(ResponseChannel<Response>, SwapResponse)>,
+    send_swap_response: Receiver<(ResponseChannel<SwapResponse>, SwapResponse)>,
     send_transfer_proof: Receiver<(PeerId, TransferProof)>,
     recv_transfer_proof_ack: Sender<()>,
 }
diff --git a/swap/src/protocol/alice/swap_response.rs b/swap/src/protocol/alice/swap_response.rs
index be67f7a6..650ba4b0 100644
--- a/swap/src/protocol/alice/swap_response.rs
+++ b/swap/src/protocol/alice/swap_response.rs
@@ -1,7 +1,7 @@
 use crate::{
     monero,
-    network::request_response::{CborCodec, Request, Response, Swap, TIMEOUT},
-    protocol::bob,
+    network::request_response::{CborCodec, Swap, TIMEOUT},
+    protocol::bob::SwapRequest,
 };
 use anyhow::{anyhow, Result};
 use libp2p::{
@@ -22,8 +22,8 @@ use tracing::{debug, error};
 
 #[derive(Debug)]
 pub struct OutEvent {
-    pub msg: bob::SwapRequest,
-    pub channel: ResponseChannel<Response>,
+    pub msg: SwapRequest,
+    pub channel: ResponseChannel<SwapResponse>,
 }
 
 #[derive(Copy, Clone, Debug, Serialize, Deserialize)]
@@ -37,15 +37,18 @@ pub struct SwapResponse {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<Swap>>,
+    rr: RequestResponse<CborCodec<Swap, SwapRequest, SwapResponse>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
     /// Alice always sends her messages as a response to a request from Bob.
-    pub fn send(&mut self, channel: ResponseChannel<Response>, msg: SwapResponse) -> Result<()> {
-        let msg = Response::SwapResponse(Box::new(msg));
+    pub fn send(
+        &mut self,
+        channel: ResponseChannel<SwapResponse>,
+        msg: SwapResponse,
+    ) -> Result<()> {
         self.rr
             .send_response(channel, msg)
             .map_err(|_| anyhow!("Sending swap response failed"))
@@ -55,7 +58,12 @@ impl Behaviour {
         &mut self,
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
-    ) -> Poll<NetworkBehaviourAction<RequestProtocol<CborCodec<Swap>>, OutEvent>> {
+    ) -> Poll<
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<Swap, SwapRequest, SwapResponse>>,
+            OutEvent,
+        >,
+    > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
         }
@@ -82,20 +90,22 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<SwapRequest, SwapResponse>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<SwapRequest, SwapResponse>) {
         match event {
             RequestResponseEvent::Message {
+                peer,
                 message:
                     RequestResponseMessage::Request {
                         request, channel, ..
                     },
                 ..
             } => {
-                if let Request::SwapRequest(msg) = request {
-                    debug!("Received swap request");
-                    self.events.push_back(OutEvent { msg: *msg, channel })
-                }
+                debug!("Received swap request from {}", peer);
+                self.events.push_back(OutEvent {
+                    msg: request,
+                    channel,
+                })
             }
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Response { .. },
diff --git a/swap/src/protocol/alice/transfer_proof.rs b/swap/src/protocol/alice/transfer_proof.rs
index c37b4f0b..184eab25 100644
--- a/swap/src/protocol/alice/transfer_proof.rs
+++ b/swap/src/protocol/alice/transfer_proof.rs
@@ -1,6 +1,6 @@
 use crate::{
     monero,
-    network::request_response::{CborCodec, Request, Response, TransferProofProtocol, TIMEOUT},
+    network::request_response::{CborCodec, TransferProofProtocol, TIMEOUT},
 };
 use libp2p::{
     request_response::{
@@ -34,14 +34,13 @@ pub enum OutEvent {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<TransferProofProtocol>>,
+    rr: RequestResponse<CborCodec<TransferProofProtocol, TransferProof, ()>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
     pub fn send(&mut self, bob: PeerId, msg: TransferProof) {
-        let msg = Request::TransferProof(Box::new(msg));
         let _id = self.rr.send_request(&bob, msg);
     }
 
@@ -49,8 +48,12 @@ impl Behaviour {
         &mut self,
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
-    ) -> Poll<NetworkBehaviourAction<RequestProtocol<CborCodec<TransferProofProtocol>>, OutEvent>>
-    {
+    ) -> Poll<
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<TransferProofProtocol, TransferProof, ()>>,
+            OutEvent,
+        >,
+    > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
         }
@@ -76,20 +79,18 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<TransferProof, ()>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<TransferProof, ()>) {
         match event {
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Request { .. },
                 ..
             } => panic!("Alice should never get a transfer proof request from Bob"),
             RequestResponseEvent::Message {
-                message: RequestResponseMessage::Response { response, .. },
+                message: RequestResponseMessage::Response { .. },
                 ..
             } => {
-                if let Response::TransferProof = response {
-                    self.events.push_back(OutEvent::Acknowledged);
-                }
+                self.events.push_back(OutEvent::Acknowledged);
             }
             RequestResponseEvent::InboundFailure { error, .. } => {
                 error!("Inbound failure: {:?}", error);
diff --git a/swap/src/protocol/bob/encrypted_signature.rs b/swap/src/protocol/bob/encrypted_signature.rs
index c304d48a..c8353c4f 100644
--- a/swap/src/protocol/bob/encrypted_signature.rs
+++ b/swap/src/protocol/bob/encrypted_signature.rs
@@ -1,6 +1,4 @@
-use crate::network::request_response::{
-    CborCodec, EncryptedSignatureProtocol, Request, Response, TIMEOUT,
-};
+use crate::network::request_response::{CborCodec, EncryptedSignatureProtocol, TIMEOUT};
 use libp2p::{
     request_response::{
         handler::RequestProtocol, ProtocolSupport, RequestResponse, RequestResponseConfig,
@@ -32,14 +30,13 @@ pub enum OutEvent {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<EncryptedSignatureProtocol>>,
+    rr: RequestResponse<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
     pub fn send(&mut self, alice: PeerId, msg: EncryptedSignature) {
-        let msg = Request::EncryptedSignature(Box::new(msg));
         let _id = self.rr.send_request(&alice, msg);
     }
 
@@ -48,7 +45,10 @@ impl Behaviour {
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
     ) -> Poll<
-        NetworkBehaviourAction<RequestProtocol<CborCodec<EncryptedSignatureProtocol>>, OutEvent>,
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<EncryptedSignatureProtocol, EncryptedSignature, ()>>,
+            OutEvent,
+        >,
     > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
@@ -75,20 +75,18 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<EncryptedSignature, ()>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<EncryptedSignature, ()>) {
         match event {
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Request { .. },
                 ..
             } => panic!("Bob should never get a request from Alice"),
             RequestResponseEvent::Message {
-                message: RequestResponseMessage::Response { response, .. },
+                message: RequestResponseMessage::Response { .. },
                 ..
             } => {
-                if let Response::EncryptedSignature = response {
-                    self.events.push_back(OutEvent::Acknowledged);
-                }
+                self.events.push_back(OutEvent::Acknowledged);
             }
             RequestResponseEvent::InboundFailure { error, .. } => {
                 error!("Inbound failure: {:?}", error);
diff --git a/swap/src/protocol/bob/swap_request.rs b/swap/src/protocol/bob/swap_request.rs
index c57790d0..95fde3f2 100644
--- a/swap/src/protocol/bob/swap_request.rs
+++ b/swap/src/protocol/bob/swap_request.rs
@@ -1,5 +1,5 @@
 use crate::{
-    network::request_response::{CborCodec, Request, Response, Swap, TIMEOUT},
+    network::request_response::{CborCodec, Swap, TIMEOUT},
     protocol::alice::SwapResponse,
 };
 use anyhow::Result;
@@ -35,15 +35,14 @@ pub struct OutEvent {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<Swap>>,
+    rr: RequestResponse<CborCodec<Swap, SwapRequest, SwapResponse>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
 
 impl Behaviour {
     pub fn send(&mut self, alice: PeerId, swap_request: SwapRequest) -> Result<RequestId> {
-        let msg = Request::SwapRequest(Box::new(swap_request));
-        let id = self.rr.send_request(&alice, msg);
+        let id = self.rr.send_request(&alice, swap_request);
 
         Ok(id)
     }
@@ -52,7 +51,12 @@ impl Behaviour {
         &mut self,
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
-    ) -> Poll<NetworkBehaviourAction<RequestProtocol<CborCodec<Swap>>, OutEvent>> {
+    ) -> Poll<
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<Swap, SwapRequest, SwapResponse>>,
+            OutEvent,
+        >,
+    > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
         }
@@ -79,8 +83,8 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<SwapRequest, SwapResponse>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<SwapRequest, SwapResponse>) {
         match event {
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Request { .. },
@@ -90,12 +94,10 @@ impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for B
                 message: RequestResponseMessage::Response { response, .. },
                 ..
             } => {
-                if let Response::SwapResponse(swap_response) = response {
-                    debug!("Received swap response");
-                    self.events.push_back(OutEvent {
-                        swap_response: *swap_response,
-                    });
-                }
+                debug!("Received swap response");
+                self.events.push_back(OutEvent {
+                    swap_response: response,
+                });
             }
             RequestResponseEvent::InboundFailure { error, .. } => {
                 error!("Inbound failure: {:?}", error);
diff --git a/swap/src/protocol/bob/transfer_proof.rs b/swap/src/protocol/bob/transfer_proof.rs
index 6746d7cc..8306b040 100644
--- a/swap/src/protocol/bob/transfer_proof.rs
+++ b/swap/src/protocol/bob/transfer_proof.rs
@@ -1,5 +1,5 @@
 use crate::{
-    network::request_response::{CborCodec, Request, Response, TransferProofProtocol, TIMEOUT},
+    network::request_response::{CborCodec, TransferProofProtocol, TIMEOUT},
     protocol::alice::TransferProof,
 };
 use libp2p::{
@@ -28,7 +28,7 @@ pub enum OutEvent {
 #[behaviour(out_event = "OutEvent", poll_method = "poll")]
 #[allow(missing_debug_implementations)]
 pub struct Behaviour {
-    rr: RequestResponse<CborCodec<TransferProofProtocol>>,
+    rr: RequestResponse<CborCodec<TransferProofProtocol, TransferProof, ()>>,
     #[behaviour(ignore)]
     events: VecDeque<OutEvent>,
 }
@@ -38,8 +38,12 @@ impl Behaviour {
         &mut self,
         _: &mut Context<'_>,
         _: &mut impl PollParameters,
-    ) -> Poll<NetworkBehaviourAction<RequestProtocol<CborCodec<TransferProofProtocol>>, OutEvent>>
-    {
+    ) -> Poll<
+        NetworkBehaviourAction<
+            RequestProtocol<CborCodec<TransferProofProtocol, TransferProof, ()>>,
+            OutEvent,
+        >,
+    > {
         if let Some(event) = self.events.pop_front() {
             return Poll::Ready(NetworkBehaviourAction::GenerateEvent(event));
         }
@@ -65,8 +69,8 @@ impl Default for Behaviour {
     }
 }
 
-impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for Behaviour {
-    fn inject_event(&mut self, event: RequestResponseEvent<Request, Response>) {
+impl NetworkBehaviourEventProcess<RequestResponseEvent<TransferProof, ()>> for Behaviour {
+    fn inject_event(&mut self, event: RequestResponseEvent<TransferProof, ()>) {
         match event {
             RequestResponseEvent::Message {
                 message:
@@ -75,15 +79,13 @@ impl NetworkBehaviourEventProcess<RequestResponseEvent<Request, Response>> for B
                     },
                 ..
             } => {
-                if let Request::TransferProof(msg) = request {
-                    debug!("Received Transfer Proof");
-                    self.events.push_back(OutEvent::Msg(*msg));
-                    // Send back empty response so that the request/response protocol completes.
-                    let _ = self
-                        .rr
-                        .send_response(channel, Response::TransferProof)
-                        .map_err(|err| error!("Failed to send message 3: {:?}", err));
-                }
+                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));
             }
             RequestResponseEvent::Message {
                 message: RequestResponseMessage::Response { .. },