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Author: lantoli

internal/hcl/hcl.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 
 	"github.com/hashicorp/hcl/v2"
+	"github.com/hashicorp/hcl/v2/hclsyntax"
 	"github.com/hashicorp/hcl/v2/hclwrite"
 )
 
@@ -16,17 +17,21 @@ func ClusterToAdvancedCluster(config []byte) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	body := parser.Body()
-	for _, resource := range body.Blocks() {
+	for _, resource := range parser.Body().Blocks() {
 		isResource := resource.Type() == "resource"
 		labels := resource.Labels()
 		resourceName := labels[0]
 		if !isResource || resourceName != "mongodbatlas_cluster" {
 			continue
 		}
+		resourceBody := resource.Body()
+
 		// TODO: Do the full transformation
 		labels[0] = "mongodbatlas_advanced_cluster"
 		resource.SetLabels(labels)
+		resourceBody.AppendNewline()
+		appendComment(resourceBody, "Generated by atlas-cli-plugin-terraform.")
+		appendComment(resourceBody, "Please confirm that all references to this resource are updated.")
 	}
 	return parser.Bytes(), nil
 }
@@ -38,3 +43,13 @@ func getParser(config []byte) (*hclwrite.File, error) {
 	}
 	return parser, nil
 }
+
+func appendComment(body *hclwrite.Body, comment string) {
+	tokens := hclwrite.Tokens{
+		&hclwrite.Token{
+			Type:  hclsyntax.TokenComment,
+			Bytes: []byte("# " + comment + "\n"),
+		},
+	}
+	body.AppendUnstructuredTokens(tokens)
+}

internal/hcl/testdata/clu2adv/basic.out.tf

@@ -4,6 +4,9 @@ resource "resource1" "res1" {
 
 resource "mongodbatlas_advanced_cluster" "cluster1" {
   name = "name2"
+
+  # Generated by atlas-cli-plugin-terraform.
+  # Please confirm that all references to this resource are updated.
 }
 
 data "resource2" "res2" {