Example code from Chapter 7 (Library Example 1: Modules and Mixins) of Customizing Ruby

shell_output.sh

 $ chef-client --once --local-mode --config /\
Users/cnk/Code/sandbox/customizing_chef/part3_examples/solo.rb --override-runlist testcookbook::default
Starting Chef Client, version 12.3.0
[2015-07-09T17:08:42-07:00] WARN: Run List override has been provided.
[2015-07-09T17:08:42-07:00] WARN: Original Run List: []
[2015-07-09T17:08:42-07:00] WARN: Overridden Run List: [recipe[testcookbook::default]]
resolving cookbooks for run list: ["testcookbook::default"]
Synchronizing Cookbooks:
  - testcookbook
Compiling Cookbooks...
puts from the top of the UsefulMethods file
[2015-07-09T17:08:42-07:00] WARN: Chef::Log warning at the top of the UsefulMethods file
This is a puts from the top of the default recipe; node info: bar
[2015-07-09T17:08:42-07:00] WARN: You can log node info bar from a recipe using 'Chef::Log'
puts from inside a definition in the UsefulMethods file
[2015-07-09T17:08:42-07:00] WARN: Chef::Log warning from inside a definition in the UsefulMethods file
this is a puts inside a coditional in the default recipe - in else
[2015-07-09T17:08:42-07:00] WARN: No stop file found. Continuing...
Converging 3 resources
Recipe: testcookbook::default
  * log[this logged node info bar from a 'log' command] action write

  * log[something else] action write

  * ruby_block[testing a ruby block] action run
 This is a puts inside a ruby block in recipes/default.rb
[2015-07-09T17:08:42-07:00] WARN: This is a Chef::Log.warn inside a ruby block in recipes/default.rb

    - execute the ruby block testing a ruby block
[2015-07-09T17:08:42-07:00] WARN: Skipping final node save because override_runlist was given

Running handlers:
Running handlers complete
Chef Client finished, 3/3 resources updated in 1.79505 seconds

testcookbook-attributes-default.rb

default['foo'] = 'bar'

testcookbook-libraries-useful_methods.rb

module UsefulMethods
  puts "puts from the top of the UsefulMethods file"
  Chef::Log.warn('Chef::Log warning at the top of the UsefulMethods file')

  def stop_file_exists?
    puts "puts from inside a definition in the UsefulMethods file"
    Chef::Log.warn('Chef::Log warning from inside a definition in the UsefulMethods file')

    ::File.exists?("/tmp/stop_chef")
  end
end

testcookbook-recipes-default.rb

puts "This is a puts from the top of the default recipe; node info: #{node['foo']} "

Chef::Log.warn("You can log node info #{node['foo']} from a recipe using 'Chef::Log'")

log "this logged node info #{node['foo']} from a 'log' command"

::Chef::Recipe.send(:include, UsefulMethods)

if stop_file_exists?
  puts "this is a puts inside a coditional in the default recipe - in if"
  Chef::Log.fatal("Found a stop file. Stopping NOW!")
  log "something if"
  exit 1
else
  puts "this is a puts inside a coditional in the default recipe - in else"
  Chef::Log.warn("No stop file found. Continuing...")
  log "something else"
end

ruby_block "testing a ruby block" do
  block do
    puts "\n This is a puts inside a ruby block in recipes/default.rb"
    Chef::Log.warn("This is a Chef::Log.warn inside a ruby block in recipes/default.rb")
  end
  action :run
end