[Exports::CustomButtons] Refactor/Simplify

The previous implementation of this exporter used very abstract logic to
export the specific data items needed.  While incredibly DRY as a
result, it is also very hard to parse and when the underlying DB
structure changes, it is even harder to fix (#foreshadowing)

As a result, the change specifically makes it so the class is much more
direct in what it is exporting, and hopefully makes it easier to digest
on how it is working as well.

lib/task_helpers/exports/custom_buttons.rb

@@ -1,60 +1,68 @@
 module TaskHelpers
   class Exports
     class CustomButtons
-      class ExportArInstances
-        EXCLUDE_ATTRS = %w(id created_on updated_on created_at updated_at dialog_id resource_id).freeze
-
-        def self.export_object(obj, hash)
-          class_name = obj.class.name.underscore
-
-          $log.info("Exporting #{obj.class.name}: #{obj.try('name')} (ID: #{obj&.id})")
-          attrs = build_attr_list(obj.attributes)
-          # handle dialog label
-          attrs["dialog_label"] = obj.dialog&.label if obj.respond_to?(:dialog)
-          (hash[class_name] ||= []) << item = {'attributes' => attrs}
-          create_association_list(obj, item)
-          descendant_list(obj, item)
-        end
+      EXCLUDE_ATTRS = %w[id created_on updated_on created_at updated_at dialog_id resource_id].freeze
 
-        def self.build_attr_list(attrs)
-          attrs&.except(*EXCLUDE_ATTRS)
-        end
+      def initialize
+        @export_hash = {}
+      end
 
-        def self.create_association_list(obj, item)
-          associations = obj.class.try(:reflections)
-
-          if associations
-            associations = associations.collect { |model, assoc| {model => assoc.class.to_s.demodulize} }.select { |as| as.values.first != "BelongsToReflection" && as.keys.first != "all_relationships" }
-            associations.each do |assoc|
-              assoc.each do |a|
-                next if obj.try(a.first.to_sym).blank?
-                export_object(obj.try(a.first.to_sym), (item['associations'] ||= {}))
-              end
-            end
-          end
+      def export(options = {})
+        export_custom_buttons_sets
+        export_direct_custom_buttons
+
+        File.write("#{options[:directory]}/CustomButtons.yaml", YAML.dump(@export_hash))
+      end
+
+      def export_custom_buttons_sets
+        @export_hash["custom_button_set"] = []
+
+        CustomButtonSet.all.order(:id).each do |button_set|
+          log_export(button_set)
+
+          children = {}
+          export_direct_custom_buttons(button_set.custom_buttons, children)
+
+          @export_hash["custom_button_set"] << attrs_for(button_set, children)
         end
+      end
 
-        def self.descendant_list(obj, item)
-          obj.try(:children)&.each { |c| export_object(c, (item['children'] ||= {})) }
+      def export_direct_custom_buttons(buttons = direct_custom_buttons, result = @export_hash)
+        result["custom_button"] = []
+
+        buttons.each do |custom_button|
+          log_export(custom_button)
+
+          result["custom_button"] << attrs_for(custom_button)
         end
       end
 
-      def export(options = {})
-        parent_id_list = []
-        objects = CustomButton.in_region(MiqRegion.my_region_number).order(:id).where.not(:applies_to_class => %w[ServiceTemplate GenericObject])
-
-        export = objects.each_with_object({}) do |obj, export_hash|
-          if obj.try(:parent).present?
-            next if parent_id_list.include?(obj.parent.id)
-            ExportArInstances.export_object(obj.parent, export_hash)
-            parent_id_list << obj.parent.id
-          else
-            ExportArInstances.export_object(obj, export_hash)
-          end
+      private
+
+      def direct_custom_buttons
+        CustomButton.select("custom_buttons.*, relationships.resource_id")
+                    .left_outer_joins(:all_relationships)
+                    .where(:relationships => {:resource_id => nil})
+      end
+
+      def attrs_for(object, children = nil)
+        attrs               = {}
+        attrs["attributes"] = object.attributes.except(*EXCLUDE_ATTRS)
+        attrs["children"]   = children if children
+
+        if (resource_action = object.try(:resource_action))
+          attrs["associations"] = {"resource_action" => [attrs_for(resource_action)]}
+        end
+
+        if (label = object.try(:dialog).try(:label))
+          attrs["attributes"]["dialog_label"] = label
         end
 
-        export_dir = options[:directory]
-        File.write("#{export_dir}/CustomButtons.yaml", YAML.dump(export))
+        attrs
+      end
+
+      def log_export(object)
+        $log.info("Exporting #{object.class.name}: #{object.try('name')} (ID: #{object&.id})")
       end
     end
   end