T6953: add migration for old configuration

src/migration-scripts/monitoring/1-to-2

@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Copyright 2022-2024 VyOS maintainers and contributors <[email protected]>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+# T6953: merge node and frr exporter under prometheus section
+
+from vyos.configtree import ConfigTree
+
+base = ['service', 'monitoring']
+
+def migrate(config: ConfigTree) -> None:
+    if not config.exists(base):
+        # Nothing to do
+        return
+
+    if config.exists(base + ['node-exporter']):
+        tmp = config.return_value(base + ['node-exporter'])
+        config.delete(base + ['node-exporter'])
+        config.set(base + ['prometheus', 'node-exporter'], value=tmp)
+
+    if config.exists(base + ['frr-exporter']):
+        tmp = config.return_value(base + ['frr-exporter'])
+        config.delete(base + ['frr-exporter'])
+        config.set(base + ['prometheus', 'frr-exporter'], value=tmp)