Make the SwarmEvent report everything (#1515)

* Improve the SwarmEvent to report everything

* Address review

* Update swarm/src/lib.rs

Co-Authored-By: Roman Borschel <romanb@users.noreply.github.com>

Co-authored-by: Roman Borschel <romanb@users.noreply.github.com>

core/src/connection/pool.rs

@@ -44,7 +44,7 @@ use either::Either;
 use fnv::FnvHashMap;
 use futures::prelude::*;
 use smallvec::SmallVec;
-use std::{error, fmt, hash::Hash, task::Context, task::Poll};
+use std::{convert::TryFrom as _, error, fmt, hash::Hash, num::NonZeroU32, task::Context, task::Poll};
 
 /// A connection `Pool` manages a set of connections for each peer.
 pub struct Pool<TInEvent, TOutEvent, THandler, TTransErr, THandlerErr, TConnInfo = PeerId, TPeerId = PeerId> {
@@ -86,7 +86,7 @@ pub enum PoolEvent<'a, TInEvent, TOutEvent, THandler, TTransErr, THandlerErr, TC
     /// A new connection has been established.
     ConnectionEstablished {
         connection: EstablishedConnection<'a, TInEvent, TConnInfo, TPeerId>,
-        num_established: usize,
+        num_established: NonZeroU32,
     },
 
     /// An established connection has encountered an error.
@@ -99,7 +99,7 @@ pub enum PoolEvent<'a, TInEvent, TOutEvent, THandler, TTransErr, THandlerErr, TC
         /// A reference to the pool that used to manage the connection.
         pool: &'a mut Pool<TInEvent, TOutEvent, THandler, TTransErr, THandlerErr, TConnInfo, TPeerId>,
         /// The remaining number of established connections to the same peer.
-        num_established: usize,
+        num_established: u32,
     },
 
     /// A connection attempt failed.
@@ -580,7 +580,7 @@ where
                     let num_established =
                         if let Some(conns) = self.established.get_mut(connected.peer_id()) {
                             conns.remove(&id);
-                            conns.len()
+                            u32::try_from(conns.len()).unwrap()
                         } else {
                             0
                         };
@@ -600,7 +600,7 @@ where
                                             .map_or(0, |conns| conns.len());
                         if let Err(e) = self.limits.check_established(current) {
                             let connected = entry.close();
-                            let num_established = e.current;
+                            let num_established = u32::try_from(e.current).unwrap();
                             return Poll::Ready(PoolEvent::ConnectionError {
                                 id,
                                 connected,
@@ -623,7 +623,8 @@ where
                         // Add the connection to the pool.
                         let peer = entry.connected().peer_id().clone();
                         let conns = self.established.entry(peer).or_default();
-                        let num_established = conns.len() + 1;
+                        let num_established = NonZeroU32::new(u32::try_from(conns.len() + 1).unwrap())
+                            .expect("n + 1 is always non-zero; qed");
                         conns.insert(id, endpoint);
                         match self.get(id) {
                             Some(PoolConnection::Established(connection)) =>

core/src/network.rs

@@ -52,6 +52,7 @@ use fnv::{FnvHashMap};
 use futures::{prelude::*, future};
 use std::{
     collections::hash_map,
+    convert::TryFrom as _,
     error,
     fmt,
     hash::Hash,
@@ -517,7 +518,7 @@ where
         // A pending outgoing connection to a known peer failed.
         let mut attempt = dialing.remove(&peer_id).expect("by (1)");
 
-        let num_remain = attempt.next.len();
+        let num_remain = u32::try_from(attempt.next.len()).unwrap();
         let failed_addr = attempt.current.clone();
 
         let opts =

core/src/network/event.rs

@@ -42,7 +42,7 @@ use crate::{
     transport::{Transport, TransportError},
 };
 use futures::prelude::*;
-use std::{error, fmt, hash::Hash};
+use std::{error, fmt, hash::Hash, num::NonZeroU32};
 
 /// Event that can happen on the `Network`.
 pub enum NetworkEvent<'a, TTrans, TInEvent, TOutEvent, THandler, TConnInfo, TPeerId>
@@ -88,7 +88,7 @@ where
     /// A new connection arrived on a listener.
     IncomingConnection(IncomingConnectionEvent<'a, TTrans, TInEvent, TOutEvent, THandler, TConnInfo, TPeerId>),
 
-    /// A new connection was arriving on a listener, but an error happened when negotiating it.
+    /// An error happened on a connection during its initial handshake.
     ///
     /// This can include, for example, an error during the handshake of the encryption layer, or
     /// the connection unexpectedly closed.
@@ -105,8 +105,9 @@ where
     ConnectionEstablished {
         /// The newly established connection.
         connection: EstablishedConnection<'a, TInEvent, TConnInfo, TPeerId>,
-        /// The total number of established connections to the same peer.
-        num_established: usize,
+        /// The total number of established connections to the same peer, including the one that
+        /// has just been opened.
+        num_established: NonZeroU32,
     },
 
     /// An established connection to a peer has encountered an error.
@@ -118,13 +119,13 @@ where
         /// The error that occurred.
         error: ConnectionError<<THandler::Handler as ConnectionHandler>::Error>,
         /// The remaining number of established connections to the same peer.
-        num_established: usize,
+        num_established: u32,
     },
 
     /// A dialing attempt to an address of a peer failed.
     DialError {
         /// The number of remaining dialing attempts.
-        attempts_remaining: usize,
+        attempts_remaining: u32,
 
         /// Id of the peer we were trying to dial.
         peer_id: TPeerId,

core/tests/network_dial_error.rs

@@ -258,7 +258,7 @@ fn multiple_addresses_err() {
                         assert_eq!(attempts_remaining, 0);
                         return Poll::Ready(Ok(()));
                     } else {
-                        assert_eq!(attempts_remaining, addresses.len());
+                        assert_eq!(attempts_remaining, addresses.len() as u32);
                     }
                 },
                 Poll::Ready(_) => unreachable!(),