Using libraries
You can use arbitrary Ruby code within your recipes. As long as your logic isn't too complicated, it's totally fine to keep it inside your recipe. However, as soon as you start using plain Ruby more than Chef DSL, it's time to the move logic into external libraries.
Libraries provide a place to encapsulate Ruby code so that your recipes stay clean and neat.
In this section, we'll create a simple library to see how this works.
Getting ready
Make sure you have a cookbook called my_cookbook
and that the run_list
of your node includes my_cookbook
, as described in Creating and using cookbooks recipe of Chapter 1, Chef Infrastructure.
How to do it...
Let's create a library and use it in a cookbook:
Create a helper method in your own cookbook's library:
mma@laptop:~/chef-repo $ mkdir -p cookbooks/my_cookbook/libraries mma@laptop:~/chef-repo $ subl cookbooks/my_cookbook/libraries/ipaddress.rb
class Chef::Recipe def netmask(ipaddress) IPAddress(ipaddress).netmask end end
Use your...