fix: support launch templates references which use prefix (#3069)

This PR adds support for launch templates which are referenced by `name` in
a resource but use a `prefix` to launch. This means that the `name` attribute
can be `null` and prior to this change, references would not work. This change
adds a Infracost generated `name` if it is detected that the `launch_template`
has a `null` name.

internal/hcl/block.go

@@ -1359,15 +1359,35 @@ var (
  defaultGCPRegion = "us-central1"
 
  blockValueFuncs = map[string]BlockValueFunc{
- "data.aws_availability_zones": awsAvailabilityZonesValues,
- "data.google_compute_zones": googleComputeZonesValues,
- "data.aws_region": awsCurrentRegion,
- "data.aws_default_tags": awsDefaultTagValues,
- "resource.random_shuffle": randomShuffleValues,
- "resource.time_static": timeStaticValues,
+ "data.aws_availability_zones": awsAvailabilityZonesValues,
+ "data.google_compute_zones": googleComputeZonesValues,
+ "data.aws_region": awsCurrentRegion,
+ "data.aws_default_tags": awsDefaultTagValues,
+ "resource.random_shuffle": randomShuffleValues,
+ "resource.time_static": timeStaticValues,
+ "resource.aws_launch_template": launchTemplateValues,
  }
 )
 
+// launchTemplateValues returns the values for the launch template but if the
+// name attribute is not set it will generate a unique name based on the block
+// address. This is done to ensure that we can properly reference the launch
+// template, when users uses the name-prefix attribute to set a name.
+func launchTemplateValues(b *Block) cty.Value {
+ values := b.values()
+ launchTemplateData := values.AsValueMap()
+ v, ok := launchTemplateData["name"]
+
+ if !ok || v.IsNull() {
+ h := sha256.New()
+ h.Write([]byte(b.FullName()))
+ addressSha := hex.EncodeToString(h.Sum(nil))
+ launchTemplateData["name"] = cty.StringVal("hcl-" + addressSha)
+ }
+
+ return cty.ObjectVal(launchTemplateData)
+}
+
 // timeStaticValues mocks the values returned from resource.time_static which is
 // a resource that returns the attributes of the provided rfc3339 time. If none
 // is provided, it defaults to the current time.

internal/providers/terraform/aws/eks_node_group_test.go

@@ -5,6 +5,7 @@ import (
 
  "github.com/shopspring/decimal"
 
+ "github.com/infracost/infracost/internal/config"
  "github.com/infracost/infracost/internal/schema"
  "github.com/infracost/infracost/internal/testutil"
 
@@ -17,7 +18,9 @@ func TestEKSNodeGroupGoldenFile(t *testing.T) {
  t.Skip("skipping test in short mode")
  }
 
- tftest.GoldenFileResourceTests(t, "eks_node_group_test")
+ tftest.GoldenFileHCLResourceTestsWithOpts(t, "eks_node_group_test", tftest.DefaultGoldenFileOptions(), func(ctx *config.RunContext) {
+ ctx.Config.GraphEvaluator = true
+ })
 }
 
 func TestEKSNodeGroup_spot(t *testing.T) {

internal/providers/terraform/aws/testdata/eks_node_group_test/eks_node_group_test.golden

@@ -9,6 +9,14 @@
  └─ block_device_mapping[0] 
  └─ Storage (general purpose SSD, gp2) 60 GB $6.00 
 
+ aws_eks_node_group.example_with_launch_template_with_prefix 
+ └─ aws_launch_template.prefix 
+ ├─ Instance usage (Linux/UNIX, on-demand, m5.large) 2,190 hours $210.24 
+ ├─ EBS-optimized usage 2,190 hours $0.00 
+ ├─ Inference accelerator (eia1.medium) 2,190 hours $284.70 
+ └─ block_device_mapping[0] 
+ └─ Storage (general purpose SSD, gp3) 300 GB $24.00 
+
  aws_eks_node_group.example_with_launch_template_3 
  └─ aws_launch_template.foo3 
  ├─ Instance usage (Linux/UNIX, on-demand, m5.large) 2,190 hours $210.24 
@@ -64,17 +72,17 @@
  ├─ Instance usage (Linux/UNIX, on-demand, t3.medium) 730 hours $30.37 
  └─ Storage (general purpose SSD, gp2) 20 GB $2.00 
 
- OVERALL TOTAL $2,762.37 
+ OVERALL TOTAL $3,281.31 
 
 *Usage costs can be estimated by updating Infracost Cloud settings, see docs for other options.
 
 ──────────────────────────────────
-16 cloud resources were detected:
-∙ 11 were estimated
-∙ 5 were free
+18 cloud resources were detected:
+∙ 12 were estimated
+∙ 6 were free
 
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━┳━━━━━━━━━━━━┓
 ┃ Project ┃ Baseline cost ┃ Usage cost* ┃ Total cost ┃
 ┣━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╋━━━━━━━━━━━━━━━╋━━━━━━━━━━━━━╋━━━━━━━━━━━━┫
-┃ main ┃ $2,762 ┃ $0.00 ┃ $2,762 ┃
+┃ main ┃ $3,281 ┃ $0.00 ┃ $3,281 ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━┻━━━━━━━━━━━━┛

internal/providers/terraform/aws/testdata/eks_node_group_test/eks_node_group_test.tf

@@ -8,6 +8,10 @@ provider "aws" {
  secret_key = "mock_secret_key"
 }
 
+locals {
+ launch_template_name = aws_launch_template.prefix.name
+}
+
 resource "aws_eks_node_group" "example" {
  cluster_name = "test_aws_eks_node_group"
  node_group_name = "example"
@@ -341,6 +345,102 @@ resource "aws_eks_node_group" "example_with_launch_template_3" {
  }
 }
 
+resource "aws_launch_template" "prefix" {
+ name = null
+ name_prefix = "prefix-"
+
+ block_device_mappings {
+ device_name = "/dev/sda1"
+
+ ebs {
+ volume_type = "gp3"
+ volume_size = 100
+ }
+ }
+
+ capacity_reservation_specification {
+ capacity_reservation_preference = "open"
+ }
+
+ cpu_options {
+ core_count = 4
+ threads_per_core = 2
+ }
+
+ credit_specification {
+ cpu_credits = "standard"
+ }
+
+ disable_api_termination = true
+
+ ebs_optimized = true
+
+ elastic_gpu_specifications {
+ type = "test"
+ }
+
+ elastic_inference_accelerator {
+ type = "eia1.medium"
+ }
+
+ iam_instance_profile {
+ name = "test"
+ }
+
+ image_id = "ami-test"
+
+ instance_initiated_shutdown_behavior = "terminate"
+
+ instance_type = "m5.xlarge"
+
+ kernel_id = "test"
+
+ key_name = "test"
+
+ license_specification {
+ license_configuration_arn = "arn:aws:license-manager:eu-west-1:123456789012:license-configuration:lic-0123456789abcdef0123456789abcdef"
+ }
+
+ metadata_options {
+ http_endpoint = "enabled"
+ http_tokens = "required"
+ http_put_response_hop_limit = 1
+ }
+
+ network_interfaces {
+ associate_public_ip_address = true
+ }
+
+ placement {
+ availability_zone = "us-west-2a"
+ }
+
+ ram_disk_id = "test"
+
+ vpc_security_group_ids = ["example"]
+
+}
+
+resource "aws_eks_node_group" "example_with_launch_template_with_prefix" {
+ cluster_name = "test_aws_eks_node_group"
+ node_group_name = "example"
+ node_role_arn = "node_role_arn"
+ subnet_ids = ["subnet_id"]
+
+ instance_types = ["m5.large"]
+
+ scaling_config {
+ desired_size = 3
+ max_size = 1
+ min_size = 1
+ }
+
+ launch_template {
+ name = local.launch_template_name
+ version = "default_version"
+ }
+}
+
 resource "aws_launch_template" "foo3" {
  name = "foo3"