add support for http_remote_user

radicale/auth/http_remote_user.py

@@ -0,0 +1,36 @@
+# This file is part of Radicale - CalDAV and CardDAV server
+# Copyright © 2025-2025 Peter Bieringer <pb@bieringer.de>
+#
+# This library is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Radicale.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Authentication backend that takes the username from the
+``HTTP_REMOTE_USER`` header.
+
+It's intended for use with a reverse proxy. Be aware as this will be insecure
+if the reverse proxy is not configured properly.
+
+"""
+
+from typing import Tuple, Union
+
+from radicale import types
+from radicale.auth import none
+
+
+class Auth(none.Auth):
+
+    def get_external_login(self, environ: types.WSGIEnviron) -> Union[
+            Tuple[()], Tuple[str, str]]:
+        return environ.get("HTTP_REMOTE_USER", ""), ""