From 220942f650f6eab4817d37b0b58e253a0e548086 Mon Sep 17 00:00:00 2001
From: Bulat Shakirzyanov <bulat.shakirzyanov@datastax.com>
Date: Sat, 4 Oct 2014 13:40:34 -0700
Subject: [PATCH] [CASSANDRA-7825] skip ghost nodes in system.peers table

---
 lib/cassandra/cluster/control_connection.rb   |  4 +-
 .../cluster/control_connection_spec.rb        | 40 +++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/lib/cassandra/cluster/control_connection.rb b/lib/cassandra/cluster/control_connection.rb
index d9ca9b1d2..6d9285eca 100644
--- a/lib/cassandra/cluster/control_connection.rb
+++ b/lib/cassandra/cluster/control_connection.rb
@@ -277,7 +277,9 @@ def refresh_hosts_async
           ips = ::Set.new
 
           peers.each do |data|
-            ips << ip = peer_ip(data)
+            ip = peer_ip(data)
+            next unless ip
+            ips << ip
             @registry.host_found(ip, data)
           end
 
diff --git a/spec/cassandra/cluster/control_connection_spec.rb b/spec/cassandra/cluster/control_connection_spec.rb
index 7d7038bb7..d82625ec8 100644
--- a/spec/cassandra/cluster/control_connection_spec.rb
+++ b/spec/cassandra/cluster/control_connection_spec.rb
@@ -300,6 +300,46 @@ def handle_request(&handler)
           end
         end
 
+        context 'with empty peers' do
+          it 'skips empty peers' do
+            additional_rpc_addresses = additional_nodes.dup
+
+            handle_request do |request|
+              case request
+              when Protocol::QueryRequest
+                case request.cql
+                when /FROM system\.peers/
+                  rows = min_peers[0].times.map do |host_id|
+                    ip = additional_rpc_addresses.shift
+                    {
+                      'peer'            => ip,
+                      'rack'            => racks[ip],
+                      'data_center'     => data_centers[ip],
+                      'host_id'         => host_ids[ip],
+                      'rpc_address'     => bind_all_rpc_addresses ? IPAddr.new('0.0.0.0') : ip,
+                      'release_version' => release_versions[ip]
+                    }
+                  end
+
+                  rows << {
+                    'peer'            => nil,
+                    'rack'            => nil,
+                    'data_center'     => nil,
+                    'host_id'         => nil,
+                    'rpc_address'     => nil,
+                    'release_version' => nil
+                  }
+                  Protocol::RowsResultResponse.new(rows, peer_metadata, nil, nil)
+                end
+              end
+            end
+
+            control_connection.connect_async.value
+
+            expect(cluster_registry).to have(3).hosts
+          end
+        end
+
         context 'with logging' do
           it 'logs when fetching cluster state' do
             logger.stub(:debug)