From 16a78663f3cb6d5aa4e66e3183a10984df77ff5a Mon Sep 17 00:00:00 2001
From: Johan Lundberg <lundberg@sunet.se>
Date: Thu, 12 Feb 2026 14:42:26 +0100
Subject: [PATCH] feat: add configuration module with env-based settings

---
 pyproject.toml                |  3 ++-
 src/fastapi_oidc_op/config.py | 36 ++++++++++++++++++++++++++++++++++
 tests/test_config.py          | 37 +++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 1 deletion(-)
 create mode 100644 src/fastapi_oidc_op/config.py
 create mode 100644 tests/test_config.py

diff --git a/pyproject.toml b/pyproject.toml
index ccdce23..38bd484 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,8 +55,9 @@ indent-style = "space"
 docstring-code-format = true
 
 [tool.ty]
+
+[tool.ty.environment]
 python-version = "3.13"
-src = ["src"]
 
 [tool.ty.rules]
 possibly-unresolved-reference = "error"
diff --git a/src/fastapi_oidc_op/config.py b/src/fastapi_oidc_op/config.py
new file mode 100644
index 0000000..c29a0f2
--- /dev/null
+++ b/src/fastapi_oidc_op/config.py
@@ -0,0 +1,36 @@
+# src/fastapi_oidc_op/config.py
+from enum import StrEnum
+
+from pydantic_settings import BaseSettings
+
+
+class StorageBackend(StrEnum):
+    SQLITE = "sqlite"
+    MONGODB = "mongodb"
+
+
+class Settings(BaseSettings):
+    model_config = {"env_prefix": "OIDC_OP_"}
+
+    # Core
+    issuer: str
+    debug: bool = False
+
+    # Storage
+    storage_backend: StorageBackend = StorageBackend.SQLITE
+
+    # SQLite
+    sqlite_path: str = "data/oidc_op.db"
+
+    # MongoDB
+    mongodb_uri: str = "mongodb://localhost:27017"
+    mongodb_database: str = "oidc_op"
+
+    # Management RP
+    manage_client_id: str = "manage-app"
+
+    # Magic links
+    invite_ttl: int = 86400  # seconds
+
+    # Theme
+    theme: str = "default"
diff --git a/tests/test_config.py b/tests/test_config.py
new file mode 100644
index 0000000..9fb5330
--- /dev/null
+++ b/tests/test_config.py
@@ -0,0 +1,37 @@
+# tests/test_config.py
+import pytest
+
+from fastapi_oidc_op.config import Settings, StorageBackend
+
+
+def test_default_settings() -> None:
+    settings = Settings(
+        issuer="http://localhost:8000",
+    )
+    assert settings.issuer == "http://localhost:8000"
+    assert settings.storage_backend == StorageBackend.SQLITE
+    assert settings.sqlite_path == "data/oidc_op.db"
+    assert settings.manage_client_id == "manage-app"
+    assert settings.invite_ttl == 86400
+    assert settings.theme == "default"
+
+
+def test_mongodb_settings() -> None:
+    settings = Settings(
+        issuer="http://localhost:8000",
+        storage_backend=StorageBackend.MONGODB,
+        mongodb_uri="mongodb://mongo:27017",
+        mongodb_database="test_db",
+    )
+    assert settings.storage_backend == StorageBackend.MONGODB
+    assert settings.mongodb_uri == "mongodb://mongo:27017"
+    assert settings.mongodb_database == "test_db"
+
+
+def test_settings_from_env(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("OIDC_OP_ISSUER", "https://op.example.org")
+    monkeypatch.setenv("OIDC_OP_STORAGE_BACKEND", "mongodb")
+    monkeypatch.setenv("OIDC_OP_MONGODB_URI", "mongodb://remote:27017")
+    settings = Settings()  # type: ignore[call-arg]
+    assert settings.issuer == "https://op.example.org"
+    assert settings.storage_backend == StorageBackend.MONGODB