integrate parallel processing. use separate sql connection

Author: trungpham

lib/batch_api/parallel_actor.rb

@@ -6,7 +6,14 @@ class ParallelActor
 
     def run(env)
       middleware = InternalMiddleware.operation_stack
-      middleware.call(env).tap {|r| env.delete(:op) }
+
+      if defined?(ActiveRecord)
+        ActiveRecord::Base.connection_pool.with_connection do
+          middleware.call(env).tap {|r| env.delete(:op) }
+        end
+      else
+        middleware.call(env).tap {|r| env.delete(:op) }
+      end
     end
   end
 end