Merge pull request #1 from rubyengineer/implement-server-side-subscri…

…ption

Implement server side event stream subscription

README.md

@@ -23,10 +23,16 @@ And then execute:
 
     $ bundle
 
-After bundling you need to run the initial installation generator:
+After bundling you need to run the initial installation generator for javascript client usage:
 
     $ rails g shower:install
 
+## Configuration
+
+Create `config/initializers/redis.rb` and configure Redis connection:
+
+    $redis = Redis.new(host: '127.0.0.1', port: 6379)
+
 ## Usage
 ### Publishing
 
@@ -35,6 +41,14 @@ JSON using ```to_json```.
 
     Shower::Stream.publish('message.new', { username: 'anon', message: 'hello!' })
 
+### Subscription
+
+Subscribing to an event stream on server side.
+
+    Shower::Stream.subscribe(['message.new']) do |event, data| 
+      # do something with event
+      # do something with data
+    end
 
 ### Listening
 

lib/shower/stream.rb

@@ -9,5 +9,16 @@ def self.publish(event, message)
       $redis.publish(event, message.to_json)
     end
 
+    # Yield event and data back to subscribed entity
+    #
+    # @param [Array] events
+    def self.subscribe(events)
+      $redis.subscribe(events << 'heartbeat') do |on|
+        on.message do |event, data|
+          yield(event, data)
+        end
+      end
+    end
+
   end
-end
+end