--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/core/i18n.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+
+
+# SAT: a jabber client
+# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from typing import Callable, cast
+
+from libervia.backend.core.log import getLogger
+
+log = getLogger(__name__)
+
+try:
+
+    import gettext
+
+    _ = gettext.translation("libervia_backend", "i18n", fallback=True).gettext
+    _translators = {None: gettext.NullTranslations()}
+
+    def language_switch(lang=None):
+        if not lang in _translators:
+            _translators[lang] = gettext.translation(
+                "libervia_backendt", languages=[lang], fallback=True
+            )
+        _translators[lang].install()
+
+
+except ImportError:
+
+    log.warning("gettext support disabled")
+    _ = cast(Callable[[str], str], lambda msg: msg)  # Libervia doesn't support gettext
+
+    def language_switch(lang=None):
+        pass
+
+
+D_ = cast(Callable[[str], str], lambda msg: msg)  # used for deferred translations