hcl: When writting Module variables normalize the names

As in some cases, like 'tags', they have keys that cannot be converted direclty into valirables names
so we have to normailze them.

For this we reused the 'tag' logic and abstracted it to the 'util' lib so it can be shared between the 2 packages

CHANGELOG.md

@@ -18,6 +18,11 @@
 - Integration between Interpolation and Modules has been changed to not generate invalid HCL references
   ([Issue #219](https://github.com/cycloidio/terracognita/issues/219)
 
+### Fixed
+
+- Variables names will now be normalized to be valid HCL
+  ([PUll #219](https://github.com/cycloidio/terracognita/pull/227)
+
 ## [0.7.2] _2021-08-13_
 
 ### Added

hcl/writer.go

@@ -15,6 +15,7 @@ import (
 	"github.com/cycloidio/terracognita/errcode"
 	"github.com/cycloidio/terracognita/log"
 	"github.com/cycloidio/terracognita/provider"
+	"github.com/cycloidio/terracognita/util"
 	"github.com/cycloidio/terracognita/writer"
 	"github.com/hashicorp/hcl/v2/hclwrite"
 	"github.com/pkg/errors"
@@ -362,7 +363,7 @@ func walkVariables(cfg map[string]interface{}, validVariables map[string]struct{
 		case []interface{}:
 			if len(v) == 0 {
 				if hasKey(validVariables, currentKey) {
-					varName := strings.ReplaceAll(currentKey, ".", "_")
+					varName := util.NormalizeName(strings.ReplaceAll(currentKey, ".", "_"))
 					variables[varName] = map[string]interface{}{
 						"default": cfg[key],
 					}
@@ -378,7 +379,7 @@ func walkVariables(cfg map[string]interface{}, validVariables map[string]struct{
 				}
 			} else {
 				if hasKey(validVariables, currentKey) {
-					varName := strings.ReplaceAll(currentKey, ".", "_")
+					varName := util.NormalizeName(strings.ReplaceAll(currentKey, ".", "_"))
 					variables[varName] = map[string]interface{}{
 						"default": cfg[key],
 					}
@@ -389,7 +390,7 @@ func walkVariables(cfg map[string]interface{}, validVariables map[string]struct{
 			// This means is a "simple" value so we can
 			// directly replace it with the variable
 			if hasKey(validVariables, currentKey) {
-				varName := strings.ReplaceAll(currentKey, ".", "_")
+				varName := util.NormalizeName(strings.ReplaceAll(currentKey, ".", "_"))
 				variables[varName] = map[string]interface{}{
 					"default": cfg[key],
 				}

hcl/writer_test.go

@@ -332,6 +332,9 @@ resource "type" "name" {
 				"key":  "value",
 				"key2": "value",
 				"key3": []interface{}{},
+				"key4": map[string]interface{}{
+					"nested:key:4": "value4",
+				},
 			}
 			ehcl = `
 resource "type" "name" {
@@ -342,12 +345,16 @@ resource "type" "name2" {
   key = var.type_name2_key
 	key2 = var.type_name2_key2
 	key3 = var.type_name2_key3
+	key4 {
+		"nested:key:4" = var.type_name2_key4_nested_key_4
+	}
 }
 
 module "test" {
 	# type_name2_key = "value"
 	# type_name2_key2 = "value"
 	# type_name2_key3 = []
+	# type_name2_key4_nested_key_4 = "value4"
 	# type_name_key = "value"
   source = "./module-test"
 }
@@ -381,6 +388,10 @@ variable "type_name2_key3" {
 	default = []
 }
 
+variable "type_name2_key4_nested_key_4" {
+	default = "value4"
+}
+
 variable "type_name_key" {
 	default = "value"
 }

tag/tag.go

@@ -11,14 +11,14 @@ import (
 	"github.com/aws/aws-sdk-go/service/rds"
 	"github.com/chr4/pwgen"
 	"github.com/cycloidio/terracognita/errcode"
+	"github.com/cycloidio/terracognita/util"
 	"github.com/hashicorp/hcl/v2/hclsyntax"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 )
 
 // nameRegexp is the new regexp used to validate the names
 // of the resources on TF (defined on configs/configschema/internal_validate.go)
 var nameRegexp = regexp.MustCompile(`^[a-z0-9_]+$`)
-var invalidNameRegexp = regexp.MustCompile(`[^a-z0-9_]`)
 
 // Tag it's an easy representation of
 // a ec2.Filter for tags
@@ -75,8 +75,8 @@ func GetNameFromTag(key string, srd *schema.ResourceData, fallback string) strin
 		n = strings.ToLower(name.(string))
 	}
 
-	forcedN := forceResourceName(n)
-	forcedFallback := forceResourceName(fallback)
+	forcedN := util.NormalizeName(n)
+	forcedFallback := util.NormalizeName(fallback)
 
 	if isValidResourceName(n) && hclsyntax.ValidIdentifier(n) {
 		return n
@@ -97,12 +97,6 @@ func isValidResourceName(name string) bool {
 	return nameRegexp.MatchString(name)
 }
 
-// forceResourceName will try to replace all the
-// invalid characters of the name for _
-func forceResourceName(name string) string {
-	return invalidNameRegexp.ReplaceAllString(name, "_")
-}
-
 // GetOtherTags used to check other possible tag attributes on resources
 func GetOtherTags(provider string, srd *schema.ResourceData, filterTag Tag) (string, bool) {
 	// keep the same logic as r.data.GetOk

util/name.go

@@ -0,0 +1,14 @@
+package util
+
+import (
+	"regexp"
+	"strings"
+)
+
+var invalidNameRegexp = regexp.MustCompile(`[^a-z0-9_]`)
+
+// NormalizeName will convert the n into an low case alphanumeric value
+// and the invalid characters will be replaced by '_'
+func NormalizeName(n string) string {
+	return invalidNameRegexp.ReplaceAllString(strings.ToLower(n), "_")
+}

util/name_test.go

@@ -0,0 +1,37 @@
+package util_test
+
+import (
+	"testing"
+
+	"github.com/cycloidio/terracognita/util"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNormalizeName(t *testing.T) {
+	tests := []struct {
+		Name     string
+		In       string
+		Expected string
+	}{
+		{
+			Name:     "NoChange",
+			In:       "in",
+			Expected: "in",
+		},
+		{
+			Name:     "UpperCase",
+			In:       "IN",
+			Expected: "in",
+		},
+		{
+			Name:     "Invalid",
+			In:       ":a",
+			Expected: "_a",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			assert.Equal(t, tt.Expected, util.NormalizeName(tt.In))
+		})
+	}
+}