Fix domain history csv

app/controllers/admin/domain_versions_controller.rb

@@ -88,5 +88,17 @@ module Admin
 
       params_copy
     end
+
+    def render_by_format(page, filename)
+      respond_to do |format|
+        format.html { render page }
+        format.csv do
+          raw_csv = csv_generate
+          send_data raw_csv,
+                    filename: "#{filename}_#{Time.zone.now.to_formatted_s(:number)}.csv",
+                    type: "#{Mime[:csv]}; charset=utf-8"
+        end
+      end
+    end
   end
 end

app/helpers/object_versions_helper.rb

@@ -1,4 +1,6 @@
 module ObjectVersionsHelper
+  CSV_HEADER = ['Name', 'Registrant', 'Registrar', 'Action', 'Created at'].freeze
+
   def attach_existing_fields(version, new_object)
     version.object_changes.to_h.each do |key, value|
       method_name = "#{key}=".to_sym
@@ -11,9 +13,45 @@ module ObjectVersionsHelper
     version.object.to_h.select { |key, _value| field_names.include?(key) }
   end
 
+  def csv_generate
+    CSV.generate do |csv|
+      csv << CSV_HEADER
+      @versions.each do |version|
+        attributes = only_present_fields(version, Domain)
+        domain = Domain.new(attributes)
+        attach_existing_fields(version, domain) unless version.event == 'destroy'
+
+        csv << create_row(domain, version)
+      end
+    end
+  end
+
   private
 
   def event_value(version, val)
     version.event == 'destroy' ? val.first : val.last
   end
+
+  def registrant_name(domain, version)
+    if domain.registrant
+      domain.registrant.name
+    else
+      contact = Contact.all_versions_for([domain.registrant_id], version.created_at).first
+      if contact.nil? && ver = Version::ContactVersion.where(item_id: domain.registrant_id).last
+        merged_obj = ver.object_changes.to_h.each_with_object({}) {|(k,v), o| o[k] = v.last }
+        result = ver.object.to_h.merge(merged_obj)&.slice(*Contact&.column_names)
+        contact = Contact.new(result)
+      end
+      contact.try(:name) || 'Deleted'
+    end
+  end
+
+  def create_row(domain, version)
+    name = domain.name
+    registrant = registrant_name(domain, version)
+    registrar = domain.registrar
+    event = version.event
+    created_at = version.created_at.to_formatted_s(:db)
+    [name, registrant, registrar, event, created_at]
+  end
 end