fix(check): custom check folder validation (#9335)

prowler/CHANGELOG.md

@@ -14,6 +14,7 @@ All notable changes to the **Prowler SDK** are documented in this file.
 
 ### Fixed
 - `sharepoint_external_sharing_managed` check to handle external sharing disabled at organization level [(#9298)](https://github.com/prowler-cloud/prowler/pull/9298)
+- Custom check folder metadata validation [(#9335)](https://github.com/prowler-cloud/prowler/pull/9335)
 - Support multiple Exchange mailbox policies in M365 `exchange_mailbox_policy_additional_storage_restricted` check [(#9241)](https://github.com/prowler-cloud/prowler/pull/9241)
 
 ---

prowler/__main__.py

@@ -24,6 +24,7 @@ from prowler.lib.check.check import (
     list_checks_json,
     list_fixers,
     list_services,
+    load_custom_checks_metadata,
     parse_checks_from_file,
     parse_checks_from_folder,
     print_categories,
@@ -185,6 +186,11 @@ def prowler():
     logger.debug("Loading checks metadata from .metadata.json files")
     bulk_checks_metadata = CheckMetadata.get_bulk(provider)
 
+    # Load custom checks metadata before validation
+    if checks_folder:
+        custom_folder_metadata = load_custom_checks_metadata(checks_folder)
+        bulk_checks_metadata.update(custom_folder_metadata)
+
     if args.list_categories:
         print_categories(list_categories(bulk_checks_metadata))
         sys.exit()

prowler/lib/check/check.py

@@ -14,7 +14,7 @@ from colorama import Fore, Style
 import prowler
 from prowler.config.config import orange_color
 from prowler.lib.check.custom_checks_metadata import update_check_metadata
-from prowler.lib.check.models import Check
+from prowler.lib.check.models import Check, load_check_metadata
 from prowler.lib.check.utils import recover_checks_from_provider
 from prowler.lib.logger import logger
 from prowler.lib.outputs.outputs import report
@@ -110,6 +110,48 @@ def parse_checks_from_folder(provider, input_folder: str) -> set:
         sys.exit(1)
 
 
+def load_custom_checks_metadata(input_folder: str) -> dict:
+    """
+    Load check metadata from a custom checks folder without copying the checks.
+    This is used to validate check names before the provider is initialized.
+
+    Args:
+        input_folder (str): Path to the folder containing custom checks.
+
+    Returns:
+        dict: A dictionary with CheckID as key and CheckMetadata as value.
+    """
+    custom_checks_metadata = {}
+
+    try:
+        if not os.path.isdir(input_folder):
+            return custom_checks_metadata
+
+        with os.scandir(input_folder) as checks:
+            for check in checks:
+                if check.is_dir():
+                    check_name = check.name
+                    metadata_file = os.path.join(
+                        input_folder, check_name, f"{check_name}.metadata.json"
+                    )
+                    if os.path.isfile(metadata_file):
+                        try:
+                            check_metadata = load_check_metadata(metadata_file)
+                            custom_checks_metadata[check_metadata.CheckID] = (
+                                check_metadata
+                            )
+                        except Exception as error:
+                            logger.warning(
+                                f"Could not load metadata from {metadata_file}: {error}"
+                            )
+        return custom_checks_metadata
+    except Exception as error:
+        logger.error(
+            f"{error.__class__.__name__}[{error.__traceback__.tb_lineno}] -- {error}"
+        )
+        return custom_checks_metadata
+
+
 # Load checks from custom folder
 def remove_custom_checks_module(input_folder: str, provider: str):
     # Check if input folder is a S3 URI

tests/lib/check/check_test.py

@@ -18,6 +18,7 @@ from prowler.lib.check.check import (
     list_categories,
     list_checks_json,
     list_services,
+    load_custom_checks_metadata,
     parse_checks_from_file,
     parse_checks_from_folder,
     remove_custom_checks_module,
@@ -483,6 +484,49 @@ class TestCheck:
             )
             remove_custom_checks_module(check_folder, provider)
 
+    def test_load_custom_checks_metadata(self, tmp_path):
+        """Test loading check metadata from a custom checks folder."""
+        check_name = "custom_test_check"
+        check_folder = tmp_path / check_name
+        check_folder.mkdir()
+
+        metadata = {
+            "Provider": "aws",
+            "CheckID": check_name,
+            "CheckTitle": "Test Custom Check",
+            "CheckType": [],
+            "ServiceName": "custom",
+            "SubServiceName": "",
+            "ResourceIdTemplate": "arn:aws:custom:::resource",
+            "Severity": "low",
+            "ResourceType": "AwsCustomResource",
+            "Description": "A test custom check",
+            "Risk": "Test risk",
+            "RelatedUrl": "https://example.com",
+            "Remediation": {
+                "Code": {"CLI": "", "NativeIaC": "", "Other": "", "Terraform": ""},
+                "Recommendation": {"Text": "", "Url": ""},
+            },
+            "Categories": [],
+            "DependsOn": [],
+            "RelatedTo": [],
+            "Notes": "",
+        }
+        metadata_file = check_folder / f"{check_name}.metadata.json"
+        metadata_file.write_text(json.dumps(metadata))
+
+        result = load_custom_checks_metadata(str(tmp_path))
+
+        assert check_name in result
+        assert result[check_name].CheckID == check_name
+        assert result[check_name].Provider == "aws"
+        assert result[check_name].Severity == "low"
+
+    def test_load_custom_checks_metadata_nonexistent_path(self):
+        """Test that nonexistent paths return empty dict."""
+        result = load_custom_checks_metadata("/nonexistent/path/to/checks")
+        assert result == {}
+
     def test_exclude_checks_to_run(self):
         test_cases = [
             {