Add refresh token auth routes and utilities

surfsense_backend/app/utils/auth_cookies.py

@@ -0,0 +1,29 @@
+"""Utilities for managing authentication cookies."""
+
+from fastapi import Response
+
+from app.config import config
+
+REFRESH_TOKEN_COOKIE_NAME = "refresh_token"
+
+
+def set_refresh_token_cookie(response: Response, token: str) -> None:
+    """Set the refresh token as an HTTP-only cookie."""
+    response.set_cookie(
+        key=REFRESH_TOKEN_COOKIE_NAME,
+        value=token,
+        max_age=config.REFRESH_TOKEN_LIFETIME_SECONDS,
+        httponly=True,
+        secure=True,  # Only send over HTTPS
+        samesite="lax",
+    )
+
+
+def delete_refresh_token_cookie(response: Response) -> None:
+    """Delete the refresh token cookie."""
+    response.delete_cookie(
+        key=REFRESH_TOKEN_COOKIE_NAME,
+        httponly=True,
+        secure=True,
+        samesite="lax",
+    )