Adding tests for vpc, subnets, and route tables (#31)

* Adding base-level tests for simple-example

* gitignoring test kitchen internals

* incorporating feedback from newcontext folks

* comment clean up before PR

* upgrading to kt 3.1.x

* test repaired for kt 3 compat

* removing the gemfile lock

* making md linter happy and adjusting content to match test fixture

* PR feedback and rubocop compliance

.gitignore

 .terraform
-terraform.tfstate
 *.tfstate*
+.kitchen
+terraform.tfstate
 terraform.tfvars
+Gemfile.lock

.kitchen.yml

+---
+driver:
+  name: "terraform"
+  root_module_directory: "examples/test_fixture"
+
+provisioner:
+  name: "terraform"
+
+platforms:
+  - name: "aws"
+
+verifier:
+  name: "awspec"
+
+suites:
+  - name: "default"
+    verifier:
+      name: "awspec"
+      patterns:
+      - "test/integration/default/test_vpc.rb"

.ruby-version

+2.4.2

Gemfile

+# frozen_string_literal: true
+
+ruby '2.4.2'
+
+source 'https://rubygems.org/' do
+  gem 'aws-sdk', '~> 3.0.1'
+  gem 'awspec', '~> 1.4.0'
+  gem 'kitchen-terraform', '~> 3.1'
+  gem 'kitchen-verifier-awspec', '~> 0.1.1'
+  gem 'rhcl', '~> 0.1.0'
+end

README.md

@@ -97,6 +97,20 @@ Examples
 * [Complete VPC](https://github.com/terraform-aws-modules/terraform-aws-vpc/tree/master/examples/complete-vpc)
 * Few tests and edge cases examples: [#46](https://github.com/terraform-aws-modules/terraform-aws-vpc/tree/master/examples/issue-46-no-private-subnets), [#44](https://github.com/terraform-aws-modules/terraform-aws-vpc/tree/master/examples/issue-44-asymmetric-private-subnets)
 
+
+Tests
+-------
+
+This module has been packaged with [awspec](https://github.com/k1LoW/awspec) tests through test kitchen. To run them:
+
+1. Install [rvm](https://rvm.io/rvm/install) and the ruby version specified in the [Gemfile](https://github.com/terraform-aws-modules/terraform-aws-vpc/tree/master/Gemfile).
+2. Install bundler and the gems from our Gemfile:
+```
+gem install bundler; bundle install
+```
+3. Test using `bundle exec kitchen test` from the root of the repo.
+
+
 Authors
 -------
 

examples/test_fixture/README.md

+# Test fixture of simple VPC
+
+Configuration in this directory creates a set of VPC resources to be tested by test kitchen.
+
+There is a public and private subnet created per availability zone in addition to single NAT Gateway shared between 2 availability zones.
+
+## Usage
+
+To run the tests, from the repo root execute:
+
+```bash
+$ kitchen test
+...
+Finished in 4.25 seconds (files took 2.75 seconds to load)
+20 examples, 0 failures
+
+       Finished verifying <default-aws> (0m9.03s).
+-----> Kitchen is finished. (0m9.40s)
+```
+
+This will destroy any existing test resources, create the resources afresh, run the tests, report back, and destroy the resources.

examples/test_fixture/main.tf

+provider "aws" {
+  region = "${var.region}"
+}
+
+data "aws_availability_zones" "available" {}
+
+module "vpc" {
+  source             = "../.."
+  name               = "test-example"
+  cidr               = "10.0.0.0/16"
+  azs                = ["${data.aws_availability_zones.available.names[0]}", "${data.aws_availability_zones.available.names[1]}"]
+  private_subnets    = ["10.0.1.0/24", "10.0.2.0/24"]
+  public_subnets     = ["10.0.101.0/24", "10.0.102.0/24"]
+  enable_nat_gateway = true
+  single_nat_gateway = true
+
+  tags = {
+    Owner       = "user"
+    Environment = "dev"
+  }
+}

examples/test_fixture/outputs.tf

+output "region" {
+  description = "Region we created the resources in."
+  value       = "${var.region}"
+}

examples/test_fixture/variables.tf

+variable "region" {
+  default = "eu-west-1"
+}

test/integration/default/test_vpc.rb

+# frozen_string_literal: true
+
+require 'awspec'
+require 'aws-sdk'
+require 'rhcl'
+
+# should strive to randomize the region for more robust testing
+example_main = Rhcl.parse(File.open('examples/test_fixture/main.tf'))
+vpc_name = example_main['module']['vpc']['name']
+user_tag = example_main['module']['vpc']['tags']['Owner']
+environment_tag = example_main['module']['vpc']['tags']['Environment']
+state_file = 'terraform.tfstate.d/kitchen-terraform-default-aws/terraform.tfstate'
+tf_state = JSON.parse(File.open(state_file).read)
+region = tf_state['modules'][0]['outputs']['region']['value']
+ENV['AWS_REGION'] = region
+
+ec2 = Aws::EC2::Client.new(region: region)
+azs = ec2.describe_availability_zones
+zone_names = azs.to_h[:availability_zones].first(2).map { |az| az[:zone_name] }
+
+describe vpc(vpc_name.to_s) do
+  it { should exist }
+  it { should be_available }
+  it { should have_tag('Name').value(vpc_name.to_s) }
+  it { should have_tag('Owner').value(user_tag.to_s) }
+  it { should have_tag('Environment').value(environment_tag.to_s) }
+  it { should have_route_table("#{vpc_name}-public") }
+  zone_names.each do |az|
+    it { should have_route_table("#{vpc_name}-private-#{az}") }
+  end
+end
+
+zone_names.each do |az|
+  describe subnet("#{vpc_name}-public-#{az}") do
+    it { should exist }
+    it { should be_available }
+    it { should belong_to_vpc(vpc_name.to_s) }
+    it { should have_tag('Name').value("#{vpc_name}-public-#{az}") }
+    it { should have_tag('Owner').value(user_tag.to_s) }
+    it { should have_tag('Environment').value(environment_tag.to_s) }
+  end
+end