Terraform Module Testing
Terraform Module Testing is a set of rake tasks to easily enable testing for Terraform Module developement. It allows developers to specify tests in a rake task to test remote infrastructure is created as expected when using a module. It then destroys the environment after the test has run.
Currently this repository is tightly coupled with AWS and has not been tested to work with other providers. We are actively working to change this and hope to have a more generic solution soon. If you would like to see support for your favourite cloud provider please have submit a pull request implementing support and we will be more than happy to merge your changes in.
Installation
Add this line to your application's Gemfile:
gem 'tfmodtest'
And then execute:
$ bundle
Or install it yourself as:
$ gem install tfmodtest
Getting started
A Minimal Rakefile
In the root of your repository add a Rakefile
with the following contents:
require 'tfmodtest/module_tasks'
Adding tests
In your repository create test/<my_module>/Rakefile
and add:
namespace '<your_modules_namespace>' do
# Required: Import TerraformDevKit base rake tasks.
# Set the root path of our tests to our location.
# TerraformDevKit uses this path as the base from where
# all operations are run.
ROOT_PATH = File.dirname(File.expand_path(__FILE__))
spec = Gem::Specification.find_by_name 'TerraformDevKit'
load "#{spec.gem_dir}/tasks/devkit.rake"
# Optional: Use RSpec to run tests.
begin
require 'rspec/core/rake_task'
RSpec::Core::RakeTask.new(:spec)
rescue LoadError
raise 'Rspec not found'
end
# Required: Add a hook into TerraformDevKit to
# run tests for your module.
task :custom_test, [:env] => :spec
end
The custom_test
task is a hook in TerraformDevKit that is called once all the infrastructure is created. You can see a full list of useful hooks in TerraformDevKit here
Create test/<my_module>/config/config-dev.yml
that contains:
terraform-version: 0.12.24
project-name: my module tests
aws:
profile: <profile>
region: <region>
This configuration determines where Terraform will create the infrastructure during test execution.
Finally to create your infrastructure under test place a main.tf.mustache
file in test/<my_module>
. This is the file TerraformDevKit will use to create you infrastructure.
provider "aws" {
# Use the profile specified in config/config-dev.yml
profile = "{{Profile}}"
region = "us-east-1"
}
resource "aws_s3_bucket" "b" {
# Use the Environment name as part of the bucket name
bucket = "{{Environment}}my-tf-test-bucket"
acl = "private"
tags {
Name = "My bucket"
Environment = "Dev"
}
}
Optional but recommended
awspec
is a Ruby gem for running rspec
tests against AWS infrastructure. It eases the pain of running tests against AWS:
describe cloudwatch_alarm("www.example.com-5xxErrorRate") do
it { should exist }
it { should belong_to_metric('5xxErrorRate').namespace('AWS/CloudFront') }
end
To start using awspec
follow the Getting Started
Requirements
- Terraform 0.12.0 or above
Development
To install this gem locally run rake install
You should then be able to reference it in your local projects.