When describing any complex domain like your infrastructure, it's important that you can introduce your own higher level concepts to talk about. In this example, we group together a number of AWS resources and allow you to manage them together.
In this example we'll setup 3 separate groups, each with 2 instances and 1 security group. Because each group is nearly the same (apart from the name), we'll create our own type in Puppet, and then apply that 3 times.
This is a good example of how to use Puppet to avoid repetitive effort and to create your own abstractions that fit your organization. We're able to create each group with the following one-liner:
somegroup { 'test-1': ami => 'ami-67a60d7a', region => 'sa-east-1' }Puppet defined types are an important part of the Puppet language, and when applied to the AWS module allow for creating reusable stacks of infrastructure. Maybe you want to create a type for an application stack, making it easy to add more capacity. Or, maybe you want to describe an entire environment, then duplicate it for development, staging, and production.
To run our example, with the AWS module installed as described in the README, from this directory run:
puppet apply init.pp --test
You can observe these resources using the AWS console or the puppet resource CLI, for example:
puppet resource ec2_securitygroup test-1-sg
This should create the 6 instances and 3 security groups. You can delete them with the destroy manifest when done.
puppet apply destroy.pp --test
Defined types are one of the core building blocks of the Puppet language. By using defined types you can avoid repetition and create more domain specific instances and security groups.