job.rb in beso-0.1.0

- old
+ new
@@ -1,51 +1,94 @@
-require 'comma'
-
 module Beso
   class Job
-    def initialize( name, options )
-      @name  = name.to_sym
+    def initialize( event, options )
+      @event = event.to_sym
       @table = options.delete :table
+      @since = options.delete :since
       @props = { }
+      @extra = options
     end
+    attr_reader :event
 
-    def prop( sym, *args, &block )
-      # TODO this is weak, find a better way
-      # to do what you mean to do
-      args[ 0 ] = "Prop:#{args[ 0 ] || sym.to_s.titleize}"
+    def identity( value=nil, &block )
+      @identity = value || block
+    end
 
-      @props[ sym.to_sym ] = [ args, block ]
+    def timestamp( value )
+      raise InvalidTimestampError unless value.is_a?(Symbol)
+      @timestamp = value
     end
 
-    def to_csv
-      model_class.class_exec( event_title ) do |event|
-        define_method( :event_title ) { event }
-      end
+    def prop( name, value=nil, &block )
+      raise TooManyPropertiesError if @props.length == 10
+      @props[ name.to_sym ] = value || block || name.to_sym
+    end
 
-      model_class.instance_exec( @name, @props ) do |name, props|
-        comma name do
-          id          'Identity'
-          created_at  'Timestamp' do |m|
-            m.to_i
-          end
-          event_title 'Event'
+    def to_csv( options={} )
+      raise MissingIdentityError  if @identity.nil?
+      raise MissingTimestampError if @timestamp.nil?
 
-          props.each do |sym, (args, block)|
-            self.send sym, *args, &block
-          end
+      @since ||= options.delete :since
+
+      relation = model_class.where( "#{@timestamp} >= ?", @since || first_timestamp )
+
+      return nil if relation.empty?
+
+      Beso::CSV.generate( @extra.merge( options ) ) do |csv|
+        csv << ( required_headers + custom_headers )
+
+        relation.each do |model|
+          csv << ( required_columns( model ) + custom_columns( model ) )
         end
       end
+    end
 
-      model_class.all.to_comma @name
+    def first_timestamp
+      model_class.minimum @timestamp
     end
 
+    def last_timestamp
+      model_class.maximum @timestamp
+    end
+
     protected
 
+    def required_headers
+      %w| Identity Timestamp Event |
+    end
+
+    def custom_headers
+      @props.keys.map { |name| "Prop:#{name.to_s.titleize}" }
+    end
+
+    def required_columns( model )
+      [ ].tap do |row|
+        row << block_or_value( @identity,  model )
+        row << model.send( @timestamp ).to_i
+        row << event_title
+      end
+    end
+
+    def custom_columns( model )
+      @props.values.map { |value| block_or_value( value, model ) }
+    end
+
     def event_title
-      @name.to_s.titleize
+      @event.to_s.titleize
     end
 
     def model_class
       @table.to_s.classify.constantize
+    end
+
+    def block_or_value( value, model )
+      case value
+      when Symbol
+        model.send value
+      when Proc
+        value.call model
+      else
+        value
+      end
     end
   end
 end