Allow for non-standard redis connectors

3 files changed, 22 insertions, 3 deletions

diff --git a/actioncable/CHANGELOG.md b/actioncable/CHANGELOG.md
index e671a07563..bfc229d795 100644
--- a/actioncable/CHANGELOG.md
+++ b/actioncable/CHANGELOG.md
@@ -1,3 +1,10 @@
+*  Added ActionCable::SubscriptionAdapter::EventedRedis.em_redis_connector/redis_connector and
+   ActionCable::SubscriptionAdapter::Redis.redis_connector factory methods for redis connections, 
+   so you can overwrite with your own initializers. This is used when you want to use different-than-standard Redis adapters,
+   like for Makara distributed Redis.
+
+   *DHH*
+
 ## Rails 5.0.0.beta2 (February 01, 2016) ##
 
 *   Support PostgreSQL pubsub adapter.
diff --git a/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb b/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb
index d697548cbd..af04a58c70 100644
--- a/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/evented_redis.rb
@@ -13,6 +13,14 @@ module ActionCable
     class EventedRedis < Base # :nodoc:
       @@mutex = Mutex.new
 
+      # Overwrite this factory method for EventMachine redis connections if you want to use a different Redis library than EM::Hiredis.
+      # This is needed, for example, when using Makara proxies for distributed Redis.
+      cattr_accessor(:em_redis_connector) { ->(config) { EM::Hiredis.connect(config[:url]) } }
+
+      # Overwrite this factory method for redis connections if you want to use a different Redis library than Redis.
+      # This is needed, for example, when using Makara proxies for distributed Redis.
+      cattr_accessor(:redis_connector) { ->(config) { ::Redis.new(url: config[:url]) } }
+
       def initialize(*)
         super
         @redis_connection_for_broadcasts = @redis_connection_for_subscriptions = nil
@@ -41,7 +49,7 @@ module ActionCable
         def redis_connection_for_subscriptions
           ensure_reactor_running
           @redis_connection_for_subscriptions || @server.mutex.synchronize do
-            @redis_connection_for_subscriptions ||= EM::Hiredis.connect(@server.config.cable[:url]).tap do |redis|
+            @redis_connection_for_subscriptions ||= self.class.em_redis_connector.call(@server.config.cable).tap do |redis|
               redis.on(:reconnect_failed) do
                 @logger.info "[ActionCable] Redis reconnect failed."
               end
@@ -51,7 +59,7 @@ module ActionCable
 
         def redis_connection_for_broadcasts
           @redis_connection_for_broadcasts || @server.mutex.synchronize do
-            @redis_connection_for_broadcasts ||= ::Redis.new(@server.config.cable)
+            @redis_connection_for_broadcasts ||= self.class.redis_connector.call(@server.config.cable)
           end
         end
 
diff --git a/actioncable/lib/action_cable/subscription_adapter/redis.rb b/actioncable/lib/action_cable/subscription_adapter/redis.rb
index 7076383efe..ba4934a264 100644
--- a/actioncable/lib/action_cable/subscription_adapter/redis.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/redis.rb
@@ -6,6 +6,10 @@ require 'redis'
 module ActionCable
   module SubscriptionAdapter
     class Redis < Base # :nodoc:
+      # Overwrite this factory method for redis connections if you want to use a different Redis library than Redis.
+      # This is needed, for example, when using Makara proxies for distributed Redis.
+      cattr_accessor(:redis_connector) { ->(config) { ::Redis.new(url: config[:url]) } }
+
       def initialize(*)
         super
         @listener = nil
@@ -39,7 +43,7 @@ module ActionCable
 
         def redis_connection_for_broadcasts
           @redis_connection_for_broadcasts || @server.mutex.synchronize do
-            @redis_connection_for_broadcasts ||= ::Redis.new(@server.config.cable)
+            @redis_connection_for_broadcasts ||= self.class.redis_connector.call(@server.config.cable)
           end
         end