graphviz.rb in rails-erd-0.4.0

- old
+ new

@@ -17,17 +17,14 @@
 end
 
 module RailsERD
   class Diagram
     # Create Graphviz-based diagrams based on the domain model. For easy
-    # command line graph generation, you can use rake:
+    # command line graph generation, you can use:
     #
     #   % rake erd
     #
-    # Please see the README.rdoc file for more details on how to use Rails ERD
-    # from the command line.
-    #
     # === Options
     #
     # The following options are supported:
     #
     # filename:: The file basename of the generated diagram. Defaults to +ERD+,
@@ -35,11 +32,11 @@
     # filetype:: The file type of the generated diagram. Defaults to +pdf+, which
     #            is the recommended format. Other formats may render significantly
     #            worse than a PDF file. The available formats depend on your installation
     #            of Graphviz.
     # notation:: The cardinality notation to be used. Can be +:simple+ or
-    #            +:advanced+. Refer to README.rdoc or to the examples on the project
+    #            +:bachman+. Refer to README.rdoc or to the examples on the project
     #            homepage for more information and examples.
     # orientation:: The direction of the hierarchy of entities. Either +:horizontal+
     #               or +:vertical+. Defaults to +horizontal+. The orientation of the
     #               PDF that is generated depends on the amount of hierarchy
     #               in your models.
@@ -58,13 +55,11 @@
         :pad => "0.4,0.4",
         :margin => "0,0",
         :concentrate => true,
         :labelloc => :t,
         :fontsize => 13,
-        :fontname => "Arial Bold",
-        :remincross => true,
-        :outputorder => :edgesfirst
+        :fontname => "Arial Bold"
       }
 
       # Default node attributes.
       NODE_ATTRIBUTES = {
         :shape => "Mrecord",
@@ -84,98 +79,143 @@
         :labelangle => 32,
         :labeldistance => 1.8,
         :fontsize => 7  
       }
       
-      # Define different styles to draw the cardinality of relationships.
-      CARDINALITY_STYLES = {
-        # Closed arrows for to/from many.
-        :simple => lambda { |relationship, options|
-          options[:arrowhead] = relationship.to_many? ? :normal : :none
-          options[:arrowtail] = relationship.many_to? ? :normal : :none
-        },
-
-        # Closed arrow for to/from many, UML ranges at each end.
-        :uml => lambda { |relationship, options|
-          options[:arrowsize] = 0.7
-          options[:arrowhead] = relationship.to_many? ? :vee : :none
-          options[:arrowtail] = relationship.many_to? ? :vee : :none
-          ranges = [relationship.cardinality.destination_range, relationship.cardinality.source_range].map do |range|
-            if range.min == range.max
-              "#{range.min}"
-            else
-              "#{range.min}..#{range.max == Relationship::Cardinality::Infinity ? "∗" : range.max}"
-            end
+      module Simple
+        def entity_style(entity, attributes)
+          {}.tap do |options|
+            options[:fontcolor] = options[:color] = :grey60 if entity.abstract?
           end
-          options[:headlabel], options[:taillabel] = *ranges
-        },
+        end
         
-        # Arrow for to/from many, open or closed dots for optional/mandatory.
-        :advanced => lambda { |relationship, options|
-          dst = relationship.destination_optional? ? "odot" : "dot"
-          src = relationship.source_optional? ? "odot" : "dot"
-          dst << "normal" if relationship.to_many?
-          src << "normal" if relationship.many_to?
-          options[:arrowsize] = 0.6
-          options[:arrowhead], options[:arrowtail] = dst, src
-        }
-      }
+        def relationship_style(relationship)
+          {}.tap do |options|
+            options[:style] = :dotted if relationship.indirect?
 
-      def graph
-        @graph ||= GraphViz.digraph(@domain.name) do |graph|
-          # Set all default attributes.
-          GRAPH_ATTRIBUTES.each { |attribute, value| graph[attribute] = value }
-          NODE_ATTRIBUTES.each  { |attribute, value| graph.node[attribute] = value }
-          EDGE_ATTRIBUTES.each  { |attribute, value| graph.edge[attribute] = value }
+            # Closed arrows for to/from many.
+            options[:arrowhead] = relationship.to_many? ? "normal" : "none"
+            options[:arrowtail] = relationship.many_to? ? "normal" : "none"
+          end
+        end
 
-          # Switch rank direction if we're creating a vertically oriented graph.
-          graph[:rankdir] = :TB if vertical?
-          
-          # Title of the graph itself.
-          graph[:label] = "#{title}\\n\\n" if title
+        def specialization_style(specialization)
+          { :color => :grey60, :arrowtail => :onormal, :arrowhead => :none, :arrowsize => 1.2 }
         end
       end
-      
-      # Save the diagram and return the file name that was written to.
-      def save
-        graph.output(filetype => filename)
-        filename
-      rescue StandardError => e
-        raise "Saving diagram failed. Verify that Graphviz is installed or select filetype=dot."
-      end
+    
+      module Bachman
+        include Simple
+        def relationship_style(relationship)
+          {}.tap do |options|
+            options[:style] = :dotted if relationship.indirect?
 
-      protected
+            # Participation is "look-here".
+            dst = relationship.source_optional? ? "odot" : "dot"
+            src = relationship.destination_optional? ? "odot" : "dot"
 
-      def process_entity(entity, attributes)
-        graph.add_node entity.name, entity_options(entity, attributes)
+            # Cardinality is "look-across".
+            dst << "normal" if relationship.to_many?
+            src << "normal" if relationship.many_to?
+            options[:arrowsize] = 0.6
+            options[:arrowhead], options[:arrowtail] = dst, src
+          end
+        end
       end
+      
+      module Uml
+        include Simple
+        def relationship_style(relationship)
+          {}.tap do |options|
+            options[:style] = :dotted if relationship.indirect?
 
-      def process_relationship(relationship)
-        graph.add_edge graph.get_node(relationship.source.name), graph.get_node(relationship.destination.name),
-          relationship_options(relationship)
-      end
+            options[:arrowsize] = 0.7
+            options[:arrowhead] = relationship.to_many? ? "vee" : "none"
+            options[:arrowtail] = relationship.many_to? ? "vee" : "none"
 
-      # Returns +true+ if the layout or hierarchy of the diagram should be
-      # horizontally oriented.
-      def horizontal?
-        options.orientation == :horizontal
+            ranges = [relationship.cardinality.destination_range, relationship.cardinality.source_range].map do |range|
+              if range.min == range.max
+                "#{range.min}"
+              else
+                "#{range.min}..#{range.max == Domain::Relationship::N ? "∗" : range.max}"
+              end
+            end
+            options[:headlabel], options[:taillabel] = *ranges
+          end
+        end
       end
+      
+      attr_accessor :graph
 
-      # Returns +true+ if the layout or hierarchy of the diagram should be
-      # vertically oriented.
-      def vertical?
-        !horizontal?
+      setup do
+        self.graph = GraphViz.digraph(domain.name)
+
+        # Set all default attributes.
+        GRAPH_ATTRIBUTES.each { |attribute, value| graph[attribute] = value }
+        NODE_ATTRIBUTES.each  { |attribute, value| graph.node[attribute] = value }
+        EDGE_ATTRIBUTES.each  { |attribute, value| graph.edge[attribute] = value }
+
+        # Switch rank direction if we're creating a vertically oriented graph.
+        graph[:rankdir] = :TB if options.orientation == :vertical
+        
+        # Title of the graph itself.
+        graph[:label] = "#{title}\\n\\n" if title
+        
+        # Setup notation options.
+        extend self.class.const_get(options.notation.to_s.capitalize.to_sym)
       end
+      
+      save do
+        raise "Saving diagram failed. Output directory '#{File.dirname(filename)}' does not exist." unless File.directory?(File.dirname(filename))
+        begin
+          graph.output(filetype => filename)
+          filename
+        rescue StandardError => e
+          raise "Saving diagram failed. Verify that Graphviz is installed or select filetype=dot."
+        end
+      end
 
+      each_entity do |entity, attributes|
+        draw_node entity.name, entity_options(entity, attributes)
+      end
+      
+      each_specialization do |specialization|
+        from, to = specialization.generalized, specialization.specialized
+        draw_edge from.name, to.name, specialization_options(specialization)
+      end
+      
+      each_relationship do |relationship|
+        from, to = relationship.source, relationship.destination
+        unless draw_edge from.name, to.name, relationship_options(relationship)
+          if from.children.any?
+            from.children.each do |child|
+              draw_edge child.name, to.name, relationship_options(relationship)
+            end
+          end
+        end
+      end
+      
       private
       
+      def node_exists?(name)
+        !!graph.get_node(name)
+      end
+      
+      def draw_node(name, options)
+        graph.add_node name, options
+      end
+      
+      def draw_edge(from, to, options)
+        graph.add_edge graph.get_node(from), graph.get_node(to), options if node_exists?(from) and node_exists?(to)
+      end
+
       # Returns the title to be used for the graph.
       def title
         case options.title
         when false then nil
-        when true then
-          if @domain.name then "#{@domain.name} domain model" else "Domain model" end
+        when true
+          if domain.name then "#{domain.name} domain model" else "Domain model" end
         else options.title
         end
       end
       
       # Returns the file name that will be used when saving the diagram.
@@ -186,34 +226,25 @@
       # Returns the default file extension to be used when saving the diagram.
       def filetype
         if options.filetype.to_sym == :dot then :none else options.filetype.to_sym end
       end
 
-      # Returns an options hash based on the given entity and its attributes.
       def entity_options(entity, attributes)
-        { :label => "<#{NODE_LABEL_TEMPLATE.result(binding)}>" }
+        entity_style(entity, attributes).merge :label => "<#{NODE_LABEL_TEMPLATE.result(binding)}>"
       end
       
-      # Returns an options hash 
       def relationship_options(relationship)
-        relationship_style_options(relationship).tap do |opts|
+        relationship_style(relationship).tap do |options|
           # Edges with a higher weight are optimised to be shorter and straighter.
-          opts[:weight] = relationship.strength
+          options[:weight] = relationship.strength
           
           # Indirect relationships should not influence node ranks.
-          opts[:constraint] = false if relationship.indirect?
+          options[:constraint] = false if relationship.indirect?
         end
       end
-      
-      # Returns an options hash that defines the (cardinality) style for the
-      # relationship.
-      def relationship_style_options(relationship)
-        {}.tap do |opts|
-          opts[:style] = :dotted if relationship.indirect?
-          
-          # Let cardinality style callbacks draw arrow heads and tails.
-          CARDINALITY_STYLES[options.notation][relationship, opts]
-        end
+
+      def specialization_options(specialization)
+        specialization_style(specialization)
       end
     end
   end
-end
\ No newline at end of file
+end