config.rb in slack-ruby-client-0.5.0

- old
+ new

@@ -1,21 +1,43 @@
 module Slack
   module RealTime
     module Config
+      class NoConcurrencyError < StandardError; end
+
       extend self
 
       ATTRIBUTES = [
         :token,
         :websocket_ping,
-        :websocket_proxy
+        :websocket_proxy,
+        :concurrency
       ]
 
       attr_accessor(*Config::ATTRIBUTES)
 
       def reset
         self.websocket_ping = 30
         self.websocket_proxy = nil
         self.token = nil
+        self.concurrency = method(:detect_concurrency)
+      end
+
+      def concurrency
+        (val = @concurrency).respond_to?(:call) ? val.call : val
+      end
+
+      private
+
+      def detect_concurrency
+        [:Eventmachine, :Celluloid].each do |concurrency|
+          begin
+            return Slack::RealTime::Concurrency.const_get(concurrency)
+          rescue LoadError
+            false # could not be loaded, missing dependencies
+          end
+        end
+
+        fail NoConcurrencyError, 'Missing concurrency. Add faye-websocket or celluloid-io to your Gemfile.'
       end
     end
 
     class << self
       def configure