Allow preserving files on destroy

This change introduces the `preserve_on_destroy` option for the
local_file resource. This defaults to `false`, but when set to `true`
will ensure that the file is preserved when the resource is destroyed in
Terraform.

Resolves: #7

Author: abn

internal/provider/resource_local_file.go

@@ -67,6 +67,13 @@ func resourceLocalFile() *schema.Resource {
 				ForceNew:      true,
 				ConflictsWith: []string{"content", "sensitive_content", "content_base64"},
 			},
+			"preserve_on_destroy": {
+				Type:        schema.TypeBool,
+				Description: "If true, the file will be preserved on destroy.",
+				Optional:    true,
+				Default:     false,
+				ForceNew:    true,
+			},
 		},
 	}
 }
@@ -145,6 +152,8 @@ func resourceLocalFileCreate(d *schema.ResourceData, _ interface{}) error {
 }
 
 func resourceLocalFileDelete(d *schema.ResourceData, _ interface{}) error {
-	os.Remove(d.Get("filename").(string))
+	if !d.Get("preserve_on_destroy").(bool) {
+		os.Remove(d.Get("filename").(string))
+	}
 	return nil
 }

internal/provider/resource_local_file_test.go

@@ -23,12 +23,14 @@ func TestLocalFile_Basic(t *testing.T) {
 	f = strings.ReplaceAll(f, `\`, `\\`)
 
 	var cases = []struct {
-		path    string
-		content string
-		config  string
+		path     string
+		preserve bool
+		content  string
+		config   string
 	}{
 		{
 			f,
+			false,
 			"This is some content", fmt.Sprintf(`
 resource "local_file" "file" {
   content  = "This is some content"
@@ -37,14 +39,27 @@ resource "local_file" "file" {
 		},
 		{
 			f,
+			true,
+			"This is some content", fmt.Sprintf(`
+resource "local_file" "file" {
+  content  = "This is some content"
+  filename = "%s"
+  preserve_on_destroy = true
+}`, f),
+		},
+		{
+			f,
+			false,
 			"This is some sensitive content", fmt.Sprintf(`
 resource "local_file" "file" {
   sensitive_content = "This is some sensitive content"
   filename = "%s"
+    preserve_on_destroy = false
 }`, f),
 		},
 		{
 			f,
+			false,
 			"This is some sensitive content", fmt.Sprintf(`
 resource "local_file" "file" {
   content_base64 = "VGhpcyBpcyBzb21lIHNlbnNpdGl2ZSBjb250ZW50"
@@ -53,6 +68,7 @@ resource "local_file" "file" {
 		},
 		{
 			f,
+			false,
 			"This is some sensitive content", fmt.Sprintf(`
 resource "local_file" "file" {
   content_base64 = base64encode("This is some sensitive content")
@@ -82,6 +98,12 @@ resource "local_file" "file" {
 				},
 				CheckDestroy: func(*terraform.State) error {
 					if _, err := os.Stat(tt.path); os.IsNotExist(err) {
+						if !tt.preserve {
+							return nil
+						}
+						return errors.New("local_file was destroyed when 'preserve_on_destroy' was set to true")
+					} else if tt.preserve {
+						os.Remove(tt.path)
 						return nil
 					}
 					return errors.New("local_file did not get destroyed")

website/docs/r/file.html.md

@@ -41,4 +41,6 @@ The following arguments are supported:
 
 * `directory_permission` - (Optional) The permission to set for any directories created. Expects a string. The default value is `"0777"`.
 
+* `preserve_on_destroy` - (Optional) Determines if the file created will be removed when this resource is destroyed in Terraform. Defaults to `false`.
+
 Any required parent directories will be created automatically, and any existing file with the given name will be overwritten.