Updated so it now can either read from a path or environment variable

pyproject.toml

@@ -1,11 +1,10 @@
 [project]
 name = "lib-secret-manager"
-version = "0.2.0"
+version = "0.3.0"
 description = "Shared secret manager that consumes secrets"
 readme = "README.md"
 requires-python = ">=3.10"
 authors = [{ name = "Florian Gänsejunge" }]
-dependencies = ["simple-logger-handler"]
 
 [project.optional-dependencies]
 encryption = ["cryptography==46.0.2"]

secret_manager/__init__.py

@@ -1,6 +1,5 @@
-from .credentials_loader import return_credentials, cleanup_secret_files
+import logging
+from .credentials_loader import get_secret, cleanup_secret_files, MissingCredentialError
 
-__all__ = [
+logging.getLogger(__name__).addHandler(logging.NullHandler())
-    "return_credentials",
+__all__ = ["get_secret","cleanup_secret_files","MissingCredentialError"]
-    "cleanup_secret_files",
-]

secret_manager/credentials_loader.py

@@ -1,9 +1,35 @@
-from simple_logger_handler import setup_logger
+import logging
 import os
 from typing import Set
 
-logger = setup_logger(__name__)
+logger = logging.getLogger(__name__)
 
+class MissingCredentialError(RuntimeError):
+	"""Neither the environment variable nor the secret file provided a value."""
+
+def get_secret(env_var: str, path: str | None = None) -> str:
+	"""Resolve a secret from an environment variable, falling back to a file.
+
+	Resolution order:
+		1. The environment variable ``env_var`` (if set and non-empty).
+		2. The file at ``path`` (if given and it exists).
+
+	Raises:
+		MissingCredentialError: If neither source provides a value.
+	"""
+	value = os.getenv(env_var, "").strip()
+	if value:
+		logger.debug(f"Loaded secret from environment variable {env_var}")
+		return value
+
+	if path:
+		try:
+			return return_credentials(path)
+		except FileNotFoundError:
+			pass
+
+	sources = f"environment variable {env_var}" + (f" or file {path}" if path else "")
+	raise MissingCredentialError(f"No credential found: set {sources}")
 
 def return_credentials(path: str) -> str:
 	"""Read and return credentials from a file."""