From c609b186989e062af842b5491538a98475ab6ade Mon Sep 17 00:00:00 2001
From: Anton Kaliaev <anton.kalyaev@gmail.com>
Date: Thu, 7 Dec 2017 13:17:09 -0600
Subject: [PATCH] tolerate unresolvable seeds (Refs #880)

---
 p2p/netaddress.go      | 17 +++++++++--------
 p2p/netaddress_test.go |  8 +++-----
 p2p/switch.go          |  6 +++---
 3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/p2p/netaddress.go b/p2p/netaddress.go
index d424f8c32..9cb7dd2c3 100644
--- a/p2p/netaddress.go
+++ b/p2p/netaddress.go
@@ -5,8 +5,8 @@
 package p2p
 
 import (
-	"errors"
 	"flag"
+	"fmt"
 	"net"
 	"strconv"
 	"time"
@@ -45,7 +45,6 @@ func NewNetAddress(addr net.Addr) *NetAddress {
 // address in the form of "IP:Port". Also resolves the host if host
 // is not an IP.
 func NewNetAddressString(addr string) (*NetAddress, error) {
-
 	host, portStr, err := net.SplitHostPort(addr)
 	if err != nil {
 		return nil, err
@@ -73,16 +72,18 @@ func NewNetAddressString(addr string) (*NetAddress, error) {
 
 // NewNetAddressStrings returns an array of NetAddress'es build using
 // the provided strings.
-func NewNetAddressStrings(addrs []string) ([]*NetAddress, error) {
-	netAddrs := make([]*NetAddress, len(addrs))
-	for i, addr := range addrs {
+func NewNetAddressStrings(addrs []string) ([]*NetAddress, []error) {
+	netAddrs := make([]*NetAddress, 0)
+	errs := make([]error, 0)
+	for _, addr := range addrs {
 		netAddr, err := NewNetAddressString(addr)
 		if err != nil {
-			return nil, errors.New(cmn.Fmt("Error in address %s: %v", addr, err))
+			errs = append(errs, fmt.Errorf("Error in address %s: %v", addr, err))
+		} else {
+			netAddrs = append(netAddrs, netAddr)
 		}
-		netAddrs[i] = netAddr
 	}
-	return netAddrs, nil
+	return netAddrs, errs
 }
 
 // NewNetAddressIPPort returns a new NetAddress using the provided IP
diff --git a/p2p/netaddress_test.go b/p2p/netaddress_test.go
index 7e899a314..db6147500 100644
--- a/p2p/netaddress_test.go
+++ b/p2p/netaddress_test.go
@@ -51,11 +51,9 @@ func TestNewNetAddressString(t *testing.T) {
 }
 
 func TestNewNetAddressStrings(t *testing.T) {
-	assert, require := assert.New(t), require.New(t)
-	addrs, err := NewNetAddressStrings([]string{"127.0.0.1:8080", "127.0.0.2:8080"})
-	require.Nil(err)
-
-	assert.Equal(2, len(addrs))
+	addrs, errs := NewNetAddressStrings([]string{"127.0.0.1:8080", "127.0.0.2:8080"})
+	assert.Len(t, errs, 0)
+	assert.Equal(t, 2, len(addrs))
 }
 
 func TestNewNetAddressIPPort(t *testing.T) {
diff --git a/p2p/switch.go b/p2p/switch.go
index f41b82959..4fdaec6ec 100644
--- a/p2p/switch.go
+++ b/p2p/switch.go
@@ -298,9 +298,9 @@ func (sw *Switch) startInitPeer(peer *peer) {
 
 // DialSeeds dials a list of seeds asynchronously in random order.
 func (sw *Switch) DialSeeds(addrBook *AddrBook, seeds []string) error {
-	netAddrs, err := NewNetAddressStrings(seeds)
-	if err != nil {
-		return err
+	netAddrs, errs := NewNetAddressStrings(seeds)
+	for _, err := range errs {
+		sw.Logger.Error("Error in seed's address", "err", err)
 	}
 
 	if addrBook != nil {