pass tests

Author: lantoli

internal/hcl/hcl.go

@@ -2,16 +2,29 @@ package hcl
 
 import (
 	"fmt"
+	"strconv"
 
 	"github.com/hashicorp/hcl/v2"
 	"github.com/hashicorp/hcl/v2/hclsyntax"
 	"github.com/hashicorp/hcl/v2/hclwrite"
+	"github.com/zclconf/go-cty/cty"
 )
 
 const (
-	resourceType = "resource"
-	cluster      = "mongodbatlas_cluster"
-	advCluster   = "mongodbatlas_advanced_cluster"
+	resourceType                = "resource"
+	cluster                     = "mongodbatlas_cluster"
+	advCluster                  = "mongodbatlas_advanced_cluster"
+	strReplicationSpecs         = "replication_specs"
+	strRegionConfigs            = "region_configs"
+	strElectableSpecs           = "electable_specs"
+	strProviderRegionName       = "provider_region_name"
+	strRegionName               = "region_name"
+	strProviderName             = "provider_name"
+	strBackingProviderName      = "backing_provider_name"
+	strProviderInstanceSizeName = "provider_instance_size_name"
+	strInstanceSize             = "instance_size"
+
+	errFreeCluster = "free cluster"
 )
 
 // ClusterToAdvancedCluster transforms all mongodbatlas_cluster definitions in a
@@ -34,13 +47,97 @@ func ClusterToAdvancedCluster(config []byte) ([]byte, error) {
 		// TODO: Do the full transformation
 		labels[0] = advCluster
 		resource.SetLabels(labels)
+
+		if resourceBody.FirstMatchingBlock(strReplicationSpecs, nil) == nil {
+			if err := fillFreeTier(resourceBody); err != nil {
+				return nil, err
+			}
+		}
+
 		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
 }
 
+func fillFreeTier(resourceBody *hclwrite.Body) error {
+	resourceBody.SetAttributeValue("cluster_type", cty.StringVal("REPLICASET"))
+
+	regionConfig := hclwrite.NewEmptyFile()
+	regionConfigBody := regionConfig.Body()
+	setAttrInt(regionConfig.Body(), "priority", 7)
+	if err := moveAttribute(strProviderRegionName, strRegionName, resourceBody, regionConfigBody, errFreeCluster); err != nil {
+		return err
+	}
+	if err := moveAttribute(strProviderName, strProviderName, resourceBody, regionConfigBody, errFreeCluster); err != nil {
+		return err
+	}
+	if err := moveAttribute(strBackingProviderName, strBackingProviderName, resourceBody, regionConfigBody, errFreeCluster); err != nil {
+		return err
+	}
+
+	electableSpec := hclwrite.NewEmptyFile()
+	if err := moveAttribute(strProviderInstanceSizeName, strInstanceSize, resourceBody, electableSpec.Body(), errFreeCluster); err != nil {
+		return err
+	}
+	regionConfig.Body().SetAttributeRaw(strElectableSpecs, objectTokens(electableSpec))
+
+	replicationSpec := hclwrite.NewEmptyFile()
+	replicationSpec.Body().SetAttributeRaw(strRegionConfigs, singleArrayTokens(regionConfig))
+
+	resourceBody.SetAttributeRaw(strReplicationSpecs, singleArrayTokens(replicationSpec))
+	return nil
+}
+
+func moveAttribute(fromAttrName, toAttrName string, fromBody, toBody *hclwrite.Body, errPrefix string) error {
+	attr := fromBody.GetAttribute(fromAttrName)
+	if attr == nil {
+		return fmt.Errorf("%s: attribute %s not found", errPrefix, fromAttrName)
+	}
+	fromBody.RemoveAttribute(fromAttrName)
+	toBody.SetAttributeRaw(toAttrName, attr.Expr().BuildTokens(nil))
+	return nil
+}
+
+func setAttrExpr(body *hclwrite.Body, attrName, expression string) {
+	tokens := hclwrite.Tokens{
+		{Type: hclsyntax.TokenIdent, Bytes: []byte(expression)},
+	}
+	body.SetAttributeRaw(attrName, tokens)
+}
+
+func setAttrInt(body *hclwrite.Body, attrName string, number int) {
+	tokens := hclwrite.Tokens{
+		{Type: hclsyntax.TokenNumberLit, Bytes: []byte(strconv.Itoa(number))},
+	}
+	body.SetAttributeRaw(attrName, tokens)
+}
+
+func singleArrayTokens(file *hclwrite.File) hclwrite.Tokens {
+	ret := hclwrite.Tokens{
+		{Type: hclsyntax.TokenOBrack, Bytes: []byte("[")},
+		{Type: hclsyntax.TokenOBrack, Bytes: []byte("{")},
+		{Type: hclsyntax.TokenNewline, Bytes: []byte("\n")},
+	}
+	ret = append(ret, file.BuildTokens(nil)...)
+	ret = append(ret,
+		&hclwrite.Token{Type: hclsyntax.TokenCBrack, Bytes: []byte("}")},
+		&hclwrite.Token{Type: hclsyntax.TokenCBrack, Bytes: []byte("]")})
+	return ret
+}
+
+func objectTokens(file *hclwrite.File) hclwrite.Tokens {
+	ret := hclwrite.Tokens{
+		{Type: hclsyntax.TokenOBrack, Bytes: []byte("{")},
+		{Type: hclsyntax.TokenNewline, Bytes: []byte("\n")},
+	}
+	ret = append(ret, file.BuildTokens(nil)...)
+	ret = append(ret,
+		&hclwrite.Token{Type: hclsyntax.TokenCBrack, Bytes: []byte("}")})
+	return ret
+}
+
 func getParser(config []byte) (*hclwrite.File, error) {
 	parser, diags := hclwrite.ParseConfig(config, "", hcl.Pos{Line: 1, Column: 1})
 	if diags.HasErrors() {

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

@@ -1,4 +1,8 @@
-resource "mongodbatlas_cluster" "project_cluster_free" {
+resource "resource1" "res1" {
+  name = "name1"
+}
+
+resource "mongodbatlas_cluster" "free_cluster" {
   count                       = local.use_free_cluster ? 1 : 0
   project_id                  = var.project_id
   name                        = var.cluster_name
@@ -7,3 +11,7 @@ resource "mongodbatlas_cluster" "project_cluster_free" {
   provider_region_name        = var.region
   provider_instance_size_name = "M0"
 }
+
+data "mongodbatlas_cluster" "cluster2" {
+  name = "name4"
+}

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

@@ -1,7 +1,11 @@
-resource "mongodbatlas_advanced_cluster" "project_cluster_free" {
-  count                       = local.use_free_cluster ? 1 : 0
-  project_id                  = var.project_id
-  name                        = var.cluster_name
+resource "resource1" "res1" {
+  name = "name1"
+}
+
+resource "mongodbatlas_advanced_cluster" "free_cluster" {
+  count        = local.use_free_cluster ? 1 : 0
+  project_id   = var.project_id
+  name         = var.cluster_name
   cluster_type = "REPLICASET"
   replication_specs = [{
     region_configs = [{
@@ -18,3 +22,7 @@ resource "mongodbatlas_advanced_cluster" "project_cluster_free" {
   # Generated by atlas-cli-plugin-terraform.
   # Please confirm that all references to this resource are updated.
 }
+
+data "mongodbatlas_cluster" "cluster2" {
+  name = "name4"
+}