Fix contact history csv

app/controllers/admin/contact_versions_controller.rb

@@ -1,9 +1,13 @@
 module Admin
   class ContactVersionsController < BaseController
+    include ApplicationHelper
     include ObjectVersionsHelper
 
     load_and_authorize_resource class: Version::ContactVersion
 
+    MODEL = Contact
+    CSV_HEADER = ['Name', 'ID', 'Ident', 'Registrar', 'Action', 'Created at'].freeze
+
     def index
       params[:q] ||= {}
 
@@ -56,5 +60,19 @@ module Admin
     def create_where_string(key, value)
       " AND object->>'#{key}' ~* '#{value}'"
     end
+
+    private
+
+    def render_by_format(page, filename)
+      respond_to do |format|
+        format.html { render page }
+        format.csv do
+          raw_csv = csv_generate(MODEL, CSV_HEADER)
+          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