[#4604] Add a simple rake task to update missing cost caches

lib/tasks/cache.rake

@@ -0,0 +1,20 @@
+require 'lockfile'
+
+namespace :rate_plugin do
+  namespace :cache do
+    desc "Update Time Entry cost caches"
+    task :update_cost_cache => :environment do
+      Lockfile('update_cost_cache', :retries => 0) do
+        TimeEntry.all(:conditions => {:cost => nil}).each do |time_entry|
+          begin
+            time_entry.save_cached_cost
+          rescue Rate::InvalidParameterException => ex
+            puts "Error saving #{time_entry.id}: #{ex.message}"
+          end
+          
+        end
+        
+      end
+    end
+  end
+end