1 files changed, 23 insertions, 0 deletions
diff --git a/searx/botdetection/http_accept_language.py b/searx/botdetection/http_accept_language.py
new file mode 100644
index 000000000..06743802e
--- /dev/null
+++ b/searx/botdetection/http_accept_language.py
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+# lint: pylint
+"""
+Method ``http_accept_language``
+-------------------------------
+
+The ``http_accept_language`` method evaluates a request as the request of a bot
+if the Accept-Language_ header is unset.
+
+.. _Accept-Language:
+   https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent
+
+"""
+
+
+from typing import Optional, Tuple
+import flask
+
+
+def filter_request(request: flask.Request) -> Optional[Tuple[int, str]]:
+    if request.headers.get('Accept-Language', '').strip() == '':
+        return 429, "bot detected, missing HTTP header Accept-Language"
+    return None