Simplify constructor of Bob's EventLoop

We never customize the behaviour or transport. Might as well hide
those details in the implementation.

swap/src/protocol/bob.rs

@@ -5,10 +5,7 @@ use crate::{
     database::Database,
     execution_params::ExecutionParams,
     monero, network,
-    network::{
-        peer_tracker::{self, PeerTracker},
-        transport::build,
-    },
+    network::peer_tracker::{self, PeerTracker},
     protocol::{alice, alice::TransferProof, bob},
     seed::Seed,
 };
@@ -53,7 +50,6 @@ pub struct Swap {
 pub struct Builder {
     swap_id: Uuid,
     identity: Keypair,
-    peer_id: PeerId,
     db: Database,
 
     alice_address: Multiaddr,
@@ -84,12 +80,10 @@ impl Builder {
         execution_params: ExecutionParams,
     ) -> Self {
         let identity = network::Seed::new(seed).derive_libp2p_identity();
-        let peer_id = identity.public().into_peer_id();
 
         Self {
             swap_id,
             identity,
-            peer_id,
             db,
             alice_address,
             alice_peer_id,
@@ -152,13 +146,8 @@ impl Builder {
     fn init_event_loop(
         &self,
     ) -> Result<(bob::event_loop::EventLoop, bob::event_loop::EventLoopHandle)> {
-        let bob_behaviour = bob::Behaviour::default();
-        let bob_transport = build(&self.identity)?;
-
         bob::event_loop::EventLoop::new(
-            bob_transport,
-            bob_behaviour,
-            self.peer_id,
+            &self.identity,
             self.alice_peer_id,
             self.alice_address.clone(),
             self.bitcoin_wallet.clone(),

swap/src/protocol/bob/event_loop.rs

@@ -1,7 +1,7 @@
 use crate::{
     bitcoin,
     bitcoin::EncryptedSignature,
-    network::{transport::SwapTransport, TokioExecutor},
+    network::{transport, TokioExecutor},
     protocol::{
         alice::{QuoteResponse, TransferProof},
         bob::{Behaviour, OutEvent, QuoteRequest, State0, State2},
@@ -114,18 +114,23 @@ pub struct EventLoop {
 
 impl EventLoop {
     pub fn new(
-        transport: SwapTransport,
-        behaviour: Behaviour,
-        peer_id: PeerId,
+        identity: &libp2p::core::identity::Keypair,
         alice_peer_id: PeerId,
         alice_addr: Multiaddr,
         bitcoin_wallet: Arc<bitcoin::Wallet>,
     ) -> Result<(Self, EventLoopHandle)> {
-        let mut swarm = libp2p::swarm::SwarmBuilder::new(transport, behaviour, peer_id)
-            .executor(Box::new(TokioExecutor {
-                handle: tokio::runtime::Handle::current(),
-            }))
-            .build();
+        let behaviour = Behaviour::default();
+        let transport = transport::build(identity)?;
+
+        let mut swarm = libp2p::swarm::SwarmBuilder::new(
+            transport,
+            behaviour,
+            identity.public().into_peer_id(),
+        )
+        .executor(Box::new(TokioExecutor {
+            handle: tokio::runtime::Handle::current(),
+        }))
+        .build();
 
         swarm.add_address(alice_peer_id, alice_addr);