lib/streamit/dsl.rb in streamit-0.0.5 vs lib/streamit/dsl.rb in streamit-0.0.6

@@ -1,17 +1,21 @@
 module Streamit
   module DSL
     extend ActiveSupport::Concern
-    
+
+    # A class method for ActiveRecord models
+    #
+    # Sample usage:
+    #
     # stream :create, :actor => :watcher,
     #                 :receiver => :watched_item
     #
     # stream :update, :attributes => :image_url, 
     #
     module ClassMethods
       def stream(action, options={})
-        options.assert_valid_keys(:stream_type, :actor, :subject, :receiver, :attributes)
+        options.assert_valid_keys(:actor, :subject, :receiver, :attributes)
         raise ArgumentError, ":create or :update required as first parameter" \
           unless [:create, :update].any? {|sym| sym == action }
         
         table_name = self.model_name.downcase.pluralize
         attributes = options[:attributes]
@@ -25,33 +29,45 @@
           end
         end
         
         stream_type = attr_name.nil? ? "streamit.#{table_name}.#{action}" :
                                        "streamit.#{table_name}.#{action}.#{attr_name}"
-        
+                                       
         method_name = :"_#{stream_type.gsub('.', '_')}"
+        
         define_method(method_name) do
           stream_options = [:actor, :receiver, :subject].inject({}) do |memo, sym|
             memo[sym] = options[sym] ? send(options[sym]) : (sym == :actor ? self : nil)
             memo
           end.merge(:stream_type => stream_type, :started_at => Time.now)
 
-          attr_changed = if action == :update
-            case attributes
-            when nil
-              changed?
-            when Array
-              attributes.any? { |attr| send(:"#{attr}_changed?") }
-            when Symbol
-              send(:"#{attributes}_changed?")
+          if (action != :update || instance_variable_get("@attr_changed"))
+            Streamit.save_stream!(stream_options)
+          end
+            
+          instance_variable_set("@attr_changed", false)
+        end
+        
+        if action == :update
+          before_update_method_name = "_before#{method_name}"
+          define_method(before_update_method_name) do
+            attr_changed = if action == :update
+              case attributes
+              when nil
+                changed?
+              when Array
+                attributes.any? { |attr| send(:"#{attr}_changed?") }
+              when Symbol
+                send(:"#{attributes}_changed?")
+              end
             end
+            instance_variable_set("@attr_changed", attr_changed)
           end
-          
-          Streamit.save_stream!(stream_options) if (action != :update || attr_changed)
+          send(:"before_update", before_update_method_name)
         end
         
         send(:"after_#{action}", method_name)
       end
     end
     
   end # DSL
-end # Streamit
\ No newline at end of file
+end # Streamit