Fix bug with --ignore-parent-terragrunt (#37)

Co-authored-by: dmattia <david@transcend.io>

Makefile

@@ -1,4 +1,4 @@
-VERSION=0.4.5
+VERSION=0.5.0
 PATH_BUILD=build/
 FILE_COMMAND=terragrunt-atlantis-config
 FILE_ARCH=darwin_amd64

cmd/generate.go

@@ -87,30 +87,34 @@ func makePathAbsolute(path string, parentPath string) string {
 
 // Parses the terragrunt config at <path> to find all modules it depends on
 func getDependencies(path string) ([]string, error) {
-	decodeTypes := []config.PartialDecodeSectionType{
-		config.DependencyBlock,
-		config.DependenciesBlock,
-		config.TerraformBlock,
-	}
-
 	options, err := options.NewTerragruntOptions(path)
 	if err != nil {
 		return nil, err
 	}
 	options.RunTerragrunt = cli.RunTerragrunt
 	options.Env = getEnvs()
 
-	parsedConfig, err := config.PartialParseConfigFile(path, options, nil, decodeTypes)
+	// if theres no terraform source and we're ignoring parent terragrunt configs
+	// return nils to indicate we should skip this project
+	isParent, err := isParentModule(path, options)
 	if err != nil {
 		return nil, err
 	}
-
-	// if theres no terraform source and we're ignoring parent terragrunt configs
-	// return nils to indicate we should skip this project
-	if (parsedConfig.Terraform == nil || parsedConfig.Terraform.Source == nil) && ignoreParentTerragrunt == true {
+	if ignoreParentTerragrunt && isParent {
 		return nil, nil
 	}
 
+	decodeTypes := []config.PartialDecodeSectionType{
+		config.DependencyBlock,
+		config.DependenciesBlock,
+		config.TerraformBlock,
+	}
+
+	parsedConfig, err := config.PartialParseConfigFile(path, options, nil, decodeTypes)
+	if err != nil {
+		return nil, err
+	}
+
 	dependencies, err := parseLocalDependencies(path)
 	if err != nil {
 		return nil, err

cmd/generate_test.go

@@ -143,3 +143,14 @@ func TestTerragruntDependencies(t *testing.T) {
 		filepath.Join("..", "test_examples", "terragrunt_dependency"),
 	})
 }
+
+// This test covers parent Terragrunt files that are not runnable as modules themselves.
+// Sometimes it is possible to have parent files that only are runnable when included
+// into child modules.
+func TestUnparseableParent(t *testing.T) {
+	runTest(t, filepath.Join("golden", "invalid_parent_module.yaml"), []string{
+		"--root",
+		filepath.Join("..", "test_examples", "invalid_parent_module"),
+		"--ignore-parent-terragrunt",
+	})
+}

cmd/golden/invalid_parent_module.yaml

@@ -0,0 +1,11 @@
+automerge: false
+parallel_apply: true
+parallel_plan: true
+projects:
+- autoplan:
+    enabled: false
+    when_modified:
+    - '*.hcl'
+    - '*.tf*'
+  dir: child/deep
+version: 3

cmd/parse_hcl.go

@@ -0,0 +1,48 @@
+package cmd
+
+import (
+	"github.com/gruntwork-io/terragrunt/config"
+	"github.com/gruntwork-io/terragrunt/options"
+	"github.com/gruntwork-io/terragrunt/util"
+	"github.com/hashicorp/hcl/v2/gohcl"
+	"github.com/hashicorp/hcl/v2/hclparse"
+	"github.com/zclconf/go-cty/cty/function"
+)
+
+type parsedHcl struct {
+	Terraform *terraformConfig `hcl:"terraform,block"`
+}
+
+type terraformConfig struct {
+	Source *string `hcl:"source,attr"`
+}
+
+func isParentModule(path string, terragruntOptions *options.TerragruntOptions) (bool, error) {
+	configString, err := util.ReadFileAsString(path)
+	if err != nil {
+		return false, err
+	}
+
+	parser := hclparse.NewParser()
+	file, err := parseHcl(parser, configString, path)
+	if err != nil {
+		return false, err
+	}
+
+	extensions := config.EvalContextExtensions{}
+	evalContext := config.CreateTerragruntEvalContext(path, terragruntOptions, extensions)
+
+	// Mock all the functions out so they don't do anything. Otherwise they may throw errors that we don't care about
+	evalContext.Functions = map[string]function.Function{}
+
+	// We don't need to check the errors/diagnostics coming from `DecodeBody`, as when errors come up,
+	// it will leave the partially parsed result in the output object.
+	var parsed parsedHcl
+	gohcl.DecodeBody(file.Body, evalContext, &parsed)
+
+	if parsed.Terraform == nil || parsed.Terraform.Source == nil {
+		return true, nil
+	}
+
+	return false, nil
+}

go.mod

@@ -22,6 +22,7 @@ require (
 	github.com/hashicorp/go-multierror v1.1.0 // indirect
 	github.com/hashicorp/go-uuid v1.0.2 // indirect
 	github.com/hashicorp/go-version v1.2.1 // indirect
+	github.com/hashicorp/hcl v1.0.0
 	github.com/hashicorp/hcl/v2 v2.6.0
 	github.com/hashicorp/hcl2 v0.0.0-20191002203319-fb75b3253c80
 	github.com/hashicorp/terraform v0.12.28 // indirect

main.go

@@ -3,7 +3,7 @@ package main
 import "github.com/transcend-io/terragrunt-atlantis-config/cmd"
 
 var (
-	VERSION = "0.4.4"
+	VERSION = "0.5.0"
 )
 
 func main() {

test_examples/invalid_parent_module/child/account.hcl

@@ -0,0 +1,5 @@
+locals {
+  account_name   = "prod"
+  aws_account_id = "000000000"
+  aws_profile    = "prod"
+}

test_examples/invalid_parent_module/child/deep/terragrunt.hcl

@@ -0,0 +1,11 @@
+include {
+  path = find_in_parent_folders()
+}
+
+terraform {
+  source = "git::git@github.com:transcend-io/terraform-aws-fargate-container?ref=v0.0.4"
+}
+
+inputs = {
+  foo = "bar"
+}

test_examples/invalid_parent_module/child/env.hcl

@@ -0,0 +1,3 @@
+locals {
+  environment = "prod"
+}

test_examples/invalid_parent_module/child/region.hcl

@@ -0,0 +1,3 @@
+locals {
+  aws_region = "eu-west-1"
+}

test_examples/invalid_parent_module/terragrunt.hcl

@@ -0,0 +1,56 @@
+######################################################################################################################
+# This file (and test directory) is a fork of https://github.com/gruntwork-io/terragrunt-infrastructure-live-example #
+######################################################################################################################
+
+locals {
+  account_vars = read_terragrunt_config(find_in_parent_folders("account.hcl"))
+  region_vars = read_terragrunt_config(find_in_parent_folders("region.hcl"))
+  environment_vars = read_terragrunt_config(find_in_parent_folders("env.hcl"))
+  account_name = local.account_vars.locals.account_name
+  account_id   = local.account_vars.locals.aws_account_id
+  aws_region   = local.region_vars.locals.aws_region
+}
+
+# Generate an AWS provider block
+generate "provider" {
+  path      = "provider.tf"
+  if_exists = "overwrite_terragrunt"
+  contents  = <<EOF
+provider "aws" {
+  region = "${local.aws_region}"
+  # Only these AWS Account IDs may be operated on by this template
+  allowed_account_ids = ["${local.account_id}"]
+}
+EOF
+}
+
+# Configure Terragrunt to automatically store tfstate files in an S3 bucket
+remote_state {
+  backend = "s3"
+  config = {
+    encrypt        = true
+    bucket         = "${get_env("TG_BUCKET_PREFIX", "")}terragrunt-example-terraform-state-${local.account_name}-${local.aws_region}"
+    key            = "${path_relative_to_include()}/terraform.tfstate"
+    region         = local.aws_region
+    dynamodb_table = "terraform-locks"
+  }
+  generate = {
+    path      = "backend.tf"
+    if_exists = "overwrite_terragrunt"
+  }
+}
+
+
+# ---------------------------------------------------------------------------------------------------------------------
+# GLOBAL PARAMETERS
+# These variables apply to all configurations in this subfolder. These are automatically merged into the child
+# `terragrunt.hcl` config via the include block.
+# ---------------------------------------------------------------------------------------------------------------------
+
+# Configure root level variables that all resources can inherit. This is especially helpful with multi-account configs
+# where terraform_remote_state data sources are placed directly into the modules.
+inputs = merge(
+  local.account_vars.locals,
+  local.region_vars.locals,
+  local.environment_vars.locals,
+)

test_examples/with_parent/terragrunt.hcl

@@ -0,0 +1,3 @@
+locals {
+    ahhhhhh = "pst"
+}