fix instructions for usage with chef_handler and add integration tests

.gitignore

 *.gem
+.kitchen/
+.kitchen.local.yml

.kitchen.yml

+---
+driver:
+  name: vagrant
+  pre_create_command: 'rake clean && rake build'
+  synced_folders: [
+    [ '/tmp/chef-handler-mail-build', '/tmp/build' ]
+  ]
+
+provisioner:
+  name: chef_solo
+
+platforms:
+  - name: ubuntu-12.04
+    run_list: recipe[apt]
+
+suites:
+  - name: default
+    run_list:
+      - recipe[chef-handler-mail-test]
+      - recipe[postfix]
+    attributes:

Berksfile

+site :opscode
+
+cookbook 'apt'
+cookbook 'chef_handler'
+cookbook 'postfix'
+
+cookbook 'chef-handler-mail-test', path: 'test/cookbooks/chef-handler-mail-test'

Berksfile.lock

+{
+  "sources": {
+    "apt": {
+      "locked_version": "2.3.4"
+    },
+    "chef_handler": {
+      "locked_version": "1.1.4"
+    },
+    "postfix": {
+      "locked_version": "3.0.4"
+    },
+    "chef-handler-mail-test": {
+      "path": "./test/cookbooks/chef-handler-mail-test"
+    }
+  }
+}

README.md

@@ -18,10 +18,10 @@ Using /etc/chef/config.rb
 
 Using chef_handler LWRP
 
-    chef_gem "chef-handler-mail"
-    gem "chef-handler-mail"
+    chef_gem 'chef-handler-mail'
+    require 'chef/handler/mail'
 
-    chef_handler "MailHandler" do
+    chef_handler 'MailHandler' do
        source 'chef/handler/mail'
        arguments :to_address => "root"
        action :nothing

Rakefile

@@ -7,6 +7,8 @@ GEM_VERSION = MailHandler::VERSION
 desc "Build #{GEM_NAME} gem"
 task :build do
   system "gem build #{GEM_NAME}.gemspec"
+  system "mkdir -p /tmp/chef-handler-mail-build"
+  system "cp #{GEM_NAME}-#{GEM_VERSION}.gem /tmp/chef-handler-mail-build/#{GEM_NAME}.gem"
 end
 
 desc "Push #{GEM_NAME} to rubygems.org"
@@ -16,5 +18,13 @@ end
 
 desc "Clean up build gems"
 task :clean do
-  system "rm #{GEM_NAME}-#{GEM_VERSION}.gem"
+  system "rm -f #{GEM_NAME}-#{GEM_VERSION}.gem"
+  system "rm -f test/build/#{GEM_NAME}.gem"
+end
+
+begin
+  require 'kitchen/rake_tasks'
+  Kitchen::RakeTasks.new
+rescue LoadError
+  puts ">>>>> Kitchen gem not loaded, omitting tasks" unless ENV['CI']
 end

test/cookbooks/chef-handler-mail-test/README.md

+chef-handler-mail-test Cookbook
+===============================
+
+This cookbook provides a working example of how to use Opscode's
+chef\_handler cookbook to install and enable the chef-mail-handler
+gem
+
+It is intended for integration testing of the chef-mail-handler gem
+using test-kitchen

test/cookbooks/chef-handler-mail-test/metadata.rb

+name             'chef-handler-mail-test'
+maintainer       'Mathieu Sauve-Frankel'
+maintainer_email 'msf@kisoku.net'
+license          'Apache 2.0'
+description      'Installs/Configures chef-handler-mail-test'
+long_description IO.read(File.join(File.dirname(__FILE__), 'README.md'))
+version          '0.1.0'
+
+depends          'chef_handler'

test/cookbooks/chef-handler-mail-test/recipes/default.rb

+#
+# Cookbook Name:: chef-handler-mail-test
+# Recipe:: default
+#
+# Copyright:: 2014, Mathieu Sauve-Frankel <msf@kisoku.net>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+chef_gem 'chef-handler-mail' do
+  source '/tmp/build/chef-handler-mail.gem'
+end
+require 'chef/handler/mail'
+
+chef_handler 'MailHandler' do
+   source 'chef/handler/mail'
+   arguments :to_address => "root"
+   action :nothing
+end.run_action(:enable)
+
+package 'mailutils'

test/integration/default/serverspec/handler_spec.rb

+require 'serverspec'
+include Serverspec::Helper::Exec
+include Serverspec::Helper::DetectOS
+
+describe file('/var/mail/root') do
+  its(:content) {
+    should match "Subject: Successful Chef run on node default-ubuntu-1204.vagrantup.com"
+  }
+end