From 059699736b2f3d720a6c100625a889db00d3e02b Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Mon, 10 Jun 2019 21:37:41 -0400
Subject: [PATCH] Return errors instead of panic in libp2p

---
 beacon_node/eth2-libp2p/src/service.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/beacon_node/eth2-libp2p/src/service.rs b/beacon_node/eth2-libp2p/src/service.rs
index b18a7dc51..18f7ca98c 100644
--- a/beacon_node/eth2-libp2p/src/service.rs
+++ b/beacon_node/eth2-libp2p/src/service.rs
@@ -57,7 +57,10 @@ impl Service {
         };
 
         // listen on all addresses
-        for address in config.listen_addresses().expect("invalid listen multiaddr") {
+        for address in config
+            .listen_addresses()
+            .map_err(|e| format!("Invalid listen multiaddr: {}", e))?
+        {
             match Swarm::listen_on(&mut swarm, address.clone()) {
                 Ok(mut listen_addr) => {
                     listen_addr.append(Protocol::P2p(local_peer_id.clone().into()));
@@ -68,7 +71,10 @@ impl Service {
         }
         // connect to boot nodes - these are currently stored as multiaddrs
         // Once we have discovery, can set to peerId
-        for bootnode in config.boot_nodes().expect("invalid boot node multiaddr") {
+        for bootnode in config
+            .boot_nodes()
+            .map_err(|e| format!("Invalid boot node multiaddr: {:?}", e))?
+        {
             match Swarm::dial_addr(&mut swarm, bootnode.clone()) {
                 Ok(()) => debug!(log, "Dialing bootnode: {}", bootnode),
                 Err(err) => debug!(