automate rake task using whenever gem

Gemfile

@@ -13,6 +13,7 @@ gem "puma"
 gem "bootstrap-sass"
 gem "bcrypt"
 gem "responders", "~>2.0"
+gem "whenever"
 
 group :test do
   gem "coveralls"

Gemfile.lock

@@ -70,6 +70,7 @@ GEM
       rack (>= 1.0.0)
       rack-test (>= 0.5.4)
       xpath (~> 2.0)
+    chronic (0.10.2)
     coderay (1.1.0)
     coffee-rails (4.1.0)
       coffee-script (>= 2.2.0)
@@ -284,6 +285,8 @@ GEM
       binding_of_caller (>= 0.7.2)
       railties (>= 4.0)
       sprockets-rails (>= 2.0, < 4.0)
+    whenever (0.9.4)
+      chronic (>= 0.6.3)
     xpath (2.0.0)
       nokogiri (~> 1.3)
 
@@ -325,6 +328,7 @@ DEPENDENCIES
   turbolinks
   uglifier (>= 1.3.0)
   web-console (~> 2.0)
+  whenever
 
 BUNDLED WITH
    1.10.6

config/schedule.rb

@@ -0,0 +1,31 @@
+# Use this file to easily define all of your cron jobs.
+#
+# It's helpful, but not entirely necessary to understand cron before proceeding.
+# http://en.wikipedia.org/wiki/Cron
+
+# Example:
+#
+# set :output, "/path/to/my/cron_log.log"
+#
+# every 2.hours do
+#   command "/usr/bin/some_great_command"
+#   runner "MyModel.some_method"
+#   rake "some:great:rake:task"
+# end
+#
+# every 4.days do
+#   runner "AnotherModel.prune_old_records"
+# end
+
+# Learn more: http://github.com/javan/whenever
+
+# for testing:
+# set :environment, "test"
+#
+# every 1.minutes do
+#   rake "todo:delete_items"
+# end
+
+every 1.day, at: "12:00 am" do
+  rake "todo:delete_items"
+end

spec/features/todos_automatically_delete_spec.rb

@@ -1,19 +1,14 @@
 # require "rails_helper"
-# require "rake"
 #
 # feature "Todos are automatically purged" do
 #   include TestFactories
 #
-#   rake = Rake.application
-#   rake.init
-#   rake.load_rakefile
-#
 #   let(:todo) { valid_todo }
-#
+#   # set whenever to work in test
 #   scenario "Successfully after 7 days" do
 #     old_todo = todo
 #     old_todo.update_attribute(:created_at, (Time.now.utc - 7.days))
-#     rake["todo:delete_items"].invoke
+#     Time.now.change(hour: 0)
 #     expect(Todo.find_by(id: old_todo.id)).to be nil
 #   end
 # end