fix(purge): fix preservation pattern mechanism and default values

Author: benoit-garcia

README.md

@@ -49,7 +49,7 @@ module "my_registry" {
 | <a name="input_project_id"></a> [project_id](#input_project_id) | ID of the project the namespace is associated with. Ressource will be created in the project set at the provider level if null. | `string` | `null` | no |
 | <a name="input_purge_dry_run"></a> [purge_dry_run](#input_purge_dry_run) | Prevent deletion of tags & images. | `bool` | `true` | no |
 | <a name="input_purge_log_level"></a> [purge_log_level](#input_purge_log_level) | Log Level of the purge function. Refer to the Go [slog package documentation](https://pkg.go.dev/log/slog#Level) for accepted values | `number` | `0` | no |
-| <a name="input_purge_preserve_tag_patterns"></a> [purge_preserve_tag_patterns](#input_purge_preserve_tag_patterns) | List of regex patterns for tags to preserve. By default, preserves semantic versioning tags. | `list(string)` | ```[ "^v(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$" ]``` | no |
+| <a name="input_purge_preserve_tag_patterns"></a> [purge_preserve_tag_patterns](#input_purge_preserve_tag_patterns) | List of regex patterns for tags to preserve. By default, preserves semantic versioning tags and `latest` tags. | `list(string)` | ```[ "^latest((-.+)?)$", "^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$" ]``` | no |
 | <a name="input_purge_retention_days"></a> [purge_retention_days](#input_purge_retention_days) | Number of days to keep images before deletion. | `number` | `30` | no |
 | <a name="input_purge_schedule"></a> [purge_schedule](#input_purge_schedule) | Cron schedule for the cleanup function. Set to empty string to disable scheduled cleanup. | `string` | `"0 0 * * *"` | no |
 | <a name="input_purge_timeout"></a> [purge_timeout](#input_purge_timeout) | Timeout for the cleanup function in seconds. | `number` | `300` | no |

functions.tf

@@ -62,7 +62,7 @@ resource "scaleway_function" "registry_purge" {
   environment_variables = {
     REGISTRY_NAMESPACE    = var.name
     RETENTION_DAYS        = var.purge_retention_days
-    PRESERVE_TAG_PATTERNS = join(",", var.purge_preserve_tag_patterns)
+    PRESERVE_TAG_PATTERNS = join("|", var.purge_preserve_tag_patterns)
     DRY_RUN               = var.purge_dry_run
     LOG_LEVEL             = var.purge_log_level
   }

functions/purge/handler.go

@@ -15,7 +15,7 @@ import (
 )
 
 // Default semver pattern for tag preservation
-const DefaultTagPattern string = `^v(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$`
+const DefaultTagPattern string = `^latest((-.+)?)$|^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$`
 
 // Config holds the configuration for the purge function
 type Config struct {

variables.tf

@@ -35,9 +35,12 @@ variable "purge_retention_days" {
 }
 
 variable "purge_preserve_tag_patterns" {
-  description = "List of regex patterns for tags to preserve. By default, preserves semantic versioning tags."
+  description = "List of regex patterns for tags to preserve. By default, preserves semantic versioning tags and `latest` tags."
   type        = list(string)
-  default     = ["^v(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$"]
+  default = [
+    "^latest((-.+)?)$",
+    "^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$"
+  ]
 }
 
 variable "purge_schedule" {