authority-discovery: Add log for debugging DHT authority records (#3668)

This PR adds a debug log for displaying all the public addresses that
will later be advertised in the DHT record of the authority. The
Authority DHT record will contain the address ++ `/p2p/peerID` (if not
already present).

This log enables us to check if different nodes will advertise in the
DHT record of the authority the same IP address, however with different
peer IDs.

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

substrate/client/authority-discovery/src/worker.rs

@@ -306,29 +306,30 @@ where
 	fn addresses_to_publish(&self) -> impl Iterator<Item = Multiaddr> {
 		let peer_id: Multihash = self.network.local_peer_id().into();
 		let publish_non_global_ips = self.publish_non_global_ips;
-		self.network
-			.external_addresses()
-			.into_iter()
-			.filter(move |a| {
-				if publish_non_global_ips {
-					return true
-				}
+		let addresses = self.network.external_addresses().into_iter().filter(move |a| {
+			if publish_non_global_ips {
+				return true
+			}
 
-				a.iter().all(|p| match p {
-					// The `ip_network` library is used because its `is_global()` method is stable,
-					// while `is_global()` in the standard library currently isn't.
-					multiaddr::Protocol::Ip4(ip) if !IpNetwork::from(ip).is_global() => false,
-					multiaddr::Protocol::Ip6(ip) if !IpNetwork::from(ip).is_global() => false,
-					_ => true,
-				})
-			})
-			.map(move |a| {
-				if a.iter().any(|p| matches!(p, multiaddr::Protocol::P2p(_))) {
-					a
-				} else {
-					a.with(multiaddr::Protocol::P2p(peer_id))
-				}
+			a.iter().all(|p| match p {
+				// The `ip_network` library is used because its `is_global()` method is stable,
+				// while `is_global()` in the standard library currently isn't.
+				multiaddr::Protocol::Ip4(ip) if !IpNetwork::from(ip).is_global() => false,
+				multiaddr::Protocol::Ip6(ip) if !IpNetwork::from(ip).is_global() => false,
+				_ => true,
 			})
+		});
+
+		debug!(target: LOG_TARGET, "Authority DHT record peer_id='{:?}' addresses='{:?}'", peer_id, addresses.clone().collect::<Vec<_>>());
+
+		// The address must include the peer id if not already set.
+		addresses.map(move |a| {
+			if a.iter().any(|p| matches!(p, multiaddr::Protocol::P2p(_))) {
+				a
+			} else {
+				a.with(multiaddr::Protocol::P2p(peer_id))
+			}
+		})
 	}
 
 	/// Publish own public addresses.