Merge #640 #701

640: Add new master_name param for sentinel. Fixes #531 r=badboy

Associated with issue #531.
Based on #534 with the addition of tests.
Didn't know how to keep @nguyenductung 's commit sadly but this PR does fix the issue and is tested.


701: Get tests passing with frozen-string-literals enabled. r=badboy

This one simple change ensure that all string literals can be frozen (as per the optional feature in MRI 2.3 and onwards). @twalpole has (again) beaten me to such a patch (in #590), though mine (again) does not add the pragma comment to all files. Getting their or my PRs merged in would be excellent :)

As an alternative to the pragma comment, I would recommend adding the following to your .travis.yml file to ensure regressions aren't introduced:

```yml
before_script:
- if (ruby -e "exit RUBY_VERSION.to_f >= 2.4"); then export RUBYOPT="--enable-frozen-string-literal"; fi; echo $RUBYOPT
```

This will add the flag when the tests are run on MRI 2.4 or newer (while the feature was introduced in 2.3, it doesn't seem to work reliably until 2.4). Please note: tests will currently fail when this flag is set unless test-unit is also updated (as noted in test-unit/test-unit#149).

.travis.yml

@@ -7,6 +7,7 @@ rvm:
   - 2.1
   - 2.2
   - 2.3.0
+  - 2.4.1
   - jruby-18mode
   - jruby-19mode
   - jruby-9.0.5.0
@@ -16,6 +17,9 @@ gemfile: ".travis/Gemfile"
 
 sudo: false
 
+before_script:
+- if (ruby -e "exit RUBY_VERSION.to_f >= 2.4"); then export RUBYOPT="--enable-frozen-string-literal"; fi; echo $RUBYOPT
+
 env:
   global:
     - VERBOSE=true

.travis/Gemfile

@@ -9,3 +9,9 @@ when "synchrony"
   gem "hiredis"
   gem "em-synchrony"
 end
+
+if RUBY_VERSION.to_f < 1.9
+  gem 'test-unit', '3.1.5'
+else
+  gem 'test-unit', '>= 3.2.5'
+end

Gemfile

@@ -2,3 +2,9 @@
 source 'https://rubygems.org'
 
 gemspec
+
+if RUBY_VERSION.to_f < 1.9
+  gem 'test-unit', '3.1.5'
+else
+  gem 'test-unit', '>= 3.2.5'
+end

lib/redis.rb

@@ -44,6 +44,7 @@ def self.current=(redis)
   # @option options [Boolean] :inherit_socket (false) Whether to use socket in forked process or not
   # @option options [Array] :sentinels List of sentinels to contact
   # @option options [Symbol] :role (:master) Role to fetch via Sentinel, either `:master` or `:slave`
+  # @option options [String] :master_name Master group name according to the `monitor` line in Sentinel config
   #
   # @return [Redis] a new client instance
   def initialize(options = {})

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)

lib/redis/connection/ruby.rb

@@ -39,7 +39,7 @@ def initialize(*args)
         super(*args)
 
         @timeout = @write_timeout = nil
-        @buffer = ""
+        @buffer = "".dup
       end
 
       def timeout=(timeout)

redis.gemspec

@@ -40,5 +40,5 @@ Gem::Specification.new do |s|
   s.executables   = `git ls-files -- bin/*`.split("\n").map{ |f| File.basename(f) }
 
   s.add_development_dependency("rake", "<11.0.0")
-  s.add_development_dependency("test-unit", "3.1.5")
+  s.add_development_dependency("test-unit", ">= 3.1.5")
 end

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}]