From 27cb96ea4e60da72142a21ab898e8a5b4832172e Mon Sep 17 00:00:00 2001
From: Greg <neonmd@hotmail.co.uk>
Date: Tue, 18 Oct 2016 16:42:52 +0100
Subject: [PATCH] Add new master_name param for sentinel. Fixes #531

---
 lib/redis/client.rb   |  2 +-
 test/sentinel_test.rb | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/lib/redis/client.rb b/lib/redis/client.rb
index c867f633b..d3f20eefe 100644
--- a/lib/redis/client.rb
+++ b/lib/redis/client.rb
@@ -509,7 +509,7 @@ def initialize(options)
 
           @sentinels = @options.delete(:sentinels).dup
           @role = @options.fetch(:role, "master").to_s
-          @master = @options[:host]
+          @master = @options[:master_name] || @options[:host]
         end
 
         def check(client)
diff --git a/test/sentinel_test.rb b/test/sentinel_test.rb
index 823e0762c..7e9b4e005 100644
--- a/test/sentinel_test.rb
+++ b/test/sentinel_test.rb
@@ -196,6 +196,32 @@ def test_sentinel_role_mismatch
     assert_match(/Instance role mismatch/, ex.message)
   end
 
+  def test_sentinel_master_name
+    sentinels = [{:host => "127.0.0.1", :port => 26381}]
+
+    commands = {
+      :s1 => [],
+    }
+
+    handler = lambda do |id|
+      {
+        :sentinel => lambda do |command, *args|
+          commands[id] << [command, *args]
+          ["127.0.0.1", "6381"]
+        end
+      }
+    end
+
+    RedisMock.start(handler.call(:s1)) do |s1_port|
+      sentinels[0][:port] = s1_port
+      redis = Redis.new(:url => "redis://master1", :sentinels => sentinels, :role => :master, :master_name => :new_master)
+
+      assert redis.ping
+    end
+
+    assert_equal commands[:s1], [%w[get-master-addr-by-name new_master]]
+  end
+
   def test_sentinel_retries
     sentinels = [{:host => "127.0.0.1", :port => 26381},
                  {:host => "127.0.0.1", :port => 26382}]