Updates repo structure to conform to the Terraform Registry requireme…

…nts (#98)

* Updates repo structure to conform to the Terraform Registry requirements

* fix path

* update readme

* Test public ip

* Instance state must be running 🤦‍♂️

* Explain name collisions

README.md

@@ -51,11 +51,11 @@ The two main elements of the NAT instance solution are:
 1. The NAT instance Auto Scaling Groups, one per zone, with a corresponding standby NAT Gateway
 1. The replace-route Lambda function
 
-Both are deployed by the Terraform module located in [`modules/terraform-aws-alternat`](modules/terraform-aws-alternat).
+Both are deployed by the Terraform module.
 
 ### NAT Instance Auto Scaling Group and Standby NAT Gateway
 
-The solution deploys an Auto Scaling Group (ASG) for each provided public subnet. Each ASG contains a single instance. When the instance boots, the [user data](modules/terraform-aws-alternat/alternat.sh.tftpl) initializes the instance to do the NAT stuff.
+The solution deploys an Auto Scaling Group (ASG) for each provided public subnet. Each ASG contains a single instance. When the instance boots, the [user data](alternat.sh.tftpl) initializes the instance to do the NAT stuff.
 
 By default, the ASGs are configured with a [maximum instance lifetime](https://docs.aws.amazon.com/autoscaling/ec2/userguide/asg-max-instance-lifetime.html). This is to facilitate periodic replacement of the instance to automate patching. When the maximum instance lifetime is reached (14 days by default), the following occurs:
 
@@ -123,7 +123,7 @@ docker push <your_registry_url>/<your_repo:<release tag or short git commit sha>
 
 ### Use the Terraform Module
 
-Start by reviewing the available [input variables](modules/terraform-aws-alternat/variables.tf). Example usage:
+Start by reviewing the available [input variables](variables.tf). Example usage:
 
 ```hcl
 locals {
@@ -144,7 +144,7 @@ data "aws_subnet" "subnet" {
 }
 
 module "alternat_instances" {
- source = "git::https://github.com/chime/terraform-aws-alternat.git//modules/terraform-aws-alternat?ref=v0.3.3"
+ source = "chime/alternat/aws?ref=v0.3.3"
 
  alternat_image_uri = "0123456789012.dkr.ecr.us-east-1.amazonaws.com/alternat-functions-lambda"
  alternat_image_tag = "v0.3.3"
@@ -204,10 +204,6 @@ If you are using the open source terraform-aws-vpc module, you can set `nat_gate
 
 AlterNATively, you can remove the NAT Gateways and their EIPs from your existing configuration and then `terraform import` them to allow alterNAT to manage them.
 
-#### Why isn't this module published on the Terraform registry?
-
-While we'd like for this to be available on the Terraform Registry, it requires a specific repo naming convention and folder structure that we do not want to adopt.
-
 ### Other Considerations
 
 - Read [the Amazon EC2 instance network bandwidth page](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-network-bandwidth.html) carefully. In particular:

examples/main.tf

@@ -34,7 +34,9 @@ locals {
 }
 
 module "alternat" {
- source = "../modules/terraform-aws-alternat"
+ # To use Alternat from the Terraform Registry:
+ # source = "chime/alternat/aws"
+ source = "./.."
 
  create_nat_gateways = var.create_nat_gateways
  ingress_security_group_cidr_blocks = var.private_subnets

modules/terraform-aws-alternat/lambda.tf → lambda.tf

@@ -11,7 +11,7 @@ locals {
 data "archive_file" "lambda" {
  count = var.lambda_package_type == "Zip" ? 1 : 0
  type = "zip"
- source_dir = "${path.module}/../../functions/replace-route"
+ source_dir = "${path.module}/functions/replace-route"
  excludes = ["__pycache__"]
  output_path = var.lambda_zip_path
 }

modules/terraform-aws-alternat/main.tf → main.tf

@@ -193,7 +193,7 @@ data "cloudinit_config" "config" {
 
  part {
  content_type = "text/x-shellscript"
- content = file("${path.module}/../../scripts/alternat.sh")
+ content = file("${path.module}/scripts/alternat.sh")
  }
 
  dynamic "part" {

test/alternat_test.go

@@ -15,6 +15,7 @@ import (
  ec2types "github.com/aws/aws-sdk-go-v2/service/ec2/types"
 
  terraws "github.com/gruntwork-io/terratest/modules/aws"
+ "github.com/gruntwork-io/terratest/modules/logger"
  "github.com/gruntwork-io/terratest/modules/random"
  "github.com/gruntwork-io/terratest/modules/retry"
  "github.com/gruntwork-io/terratest/modules/ssh"
@@ -25,6 +26,11 @@ import (
  "github.com/stretchr/testify/require"
 )
 
+// Maintainer's note: This test will currently cause name collisions if multiple tests run in parallel
+// in the same account. This is because the test uses a fixed name prefix for resources. This could be fixed
+// by using GetRandomStableRegion and updating some resources (such as IAM role and CloudWatch event name)
+// to use a random suffix.
+
 func TestAlternat(t *testing.T) {
  // Uncomment any of the following lines to skip that part of the test.
  // This is useful for iterating during test development.
@@ -169,7 +175,7 @@ net.ipv4.ip_local_port_range = 1024 65535
  // Validate that private route tables have routes to the Internet via NAT Gateway
  maxRetries := 12
  waitTime := 10 * time.Second
- retry.DoWithRetry(t, "Validating route through NAT Gateway", maxRetries, waitTime, func() (string, error) {
+ output := retry.DoWithRetry(t, "Validating route through NAT Gateway", maxRetries, waitTime, func() (string, error) {
  routeTables, err := getRouteTables(t, ec2Client, vpcID)
  require.NoError(t, err)
  for _, rt := range routeTables {
@@ -181,6 +187,8 @@ net.ipv4.ip_local_port_range = 1024 65535
  }
  return "All private route tables route through NAT Gateway", nil
  })
+ logger := logger.Logger{}
+ logger.Logf(t, output) 
  updateEgress(t, ec2Client, sgId, false)
  })
 }
@@ -250,6 +258,10 @@ func getNatInstancePublicIp(t *testing.T, ec2Client *ec2.Client) (string, error)
  Name: aws.String("tag:Name"),
  Values: []string{namePrefix + "*"},
  },
+ {
+ Name: aws.String("instance-state-name"),
+ Values: []string{"running"},
+ },
  },
  }
  maxRetries := 6
@@ -260,11 +272,11 @@ func getNatInstancePublicIp(t *testing.T, ec2Client *ec2.Client) (string, error)
  return "", err
  }
 
- ip := aws.ToString(result.Reservations[0].Instances[0].PublicIpAddress)
- if ip == "" {
+ publicIp := aws.ToString(result.Reservations[0].Instances[0].PublicIpAddress)
+ if publicIp == "" {
  return "", fmt.Errorf("Public IP not found")
  }
- return ip, nil
+ return publicIp, nil
  })
 
  return ip, nil

modules/terraform-aws-alternat/variables.tf → variables.tf

@@ -1,5 +1,5 @@
 variable "additional_instance_policies" {
- description = "Additional policies for the HA NAT instance IAM role."
+ description = "Additional policies for the Alternat instance IAM role."
  type = list(object({
  policy_name = string
  policy_json = string
@@ -8,13 +8,13 @@ variable "additional_instance_policies" {
 }
 
 variable "alternat_image_tag" {
- description = "The tag of the container image for the HA NAT Lambda functions."
+ description = "The tag of the container image for the Alternat Lambda functions."
  type = string
  default = "latest"
 }
 
 variable "alternat_image_uri" {
- description = "The URI of the container image for the HA NAT Lambda functions."
+ description = "The URI of the container image for the Alternat Lambda functions."
  type = string
  default = ""
 }
@@ -68,7 +68,7 @@ variable "enable_lambda_endpoint" {
 }
 
 variable "enable_ssm" {
- description = "Whether to enable SSM on the HA NAT instances."
+ description = "Whether to enable SSM on the Alternat instances."
  type = bool
  default = true
 }