xml: T6146: add utils and helper to provide priority data

1 files changed, 75 insertions, 0 deletions

diff --git a/python/vyos/priority.py b/python/vyos/priority.py
new file mode 100644
index 000000000..ab4e6d411
--- /dev/null
+++ b/python/vyos/priority.py
@@ -0,0 +1,75 @@
+# Copyright 2024 VyOS maintainers and contributors <maintainers@vyos.io>
+#
+# 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/>.
+
+from pathlib import Path
+from typing import List
+
+from vyos.xml_ref import load_reference
+from vyos.base import Warning as Warn
+
+def priority_data(d: dict) -> list:
+    def func(d, path, res, hier):
+        for k,v in d.items():
+            if not 'node_data' in v:
+                continue
+            subpath = path + [k]
+            hier_prio = hier
+            data = v.get('node_data')
+            o = data.get('owner')
+            p = data.get('priority')
+            # a few interface-definitions have priority preceding owner
+            # attribute, instead of within properties; pass in descent
+            if p is not None and o is None:
+                hier_prio = p
+            if o is not None and p is None:
+                p = hier_prio
+            if o is not None and p is not None:
+                o = Path(o.split()[0]).name
+                p = int(p)
+                res.append((subpath, o, p))
+            if isinstance(v, dict):
+                func(v, subpath, res, hier_prio)
+        return res
+    ret = func(d, [], [], 0)
+    ret = sorted(ret, key=lambda x: x[0])
+    ret = sorted(ret, key=lambda x: x[2])
+    return ret
+
+def get_priority_data() -> list:
+    xml = load_reference()
+    return priority_data(xml.ref)
+
+def priority_sort(sections: List[list[str]] = None,
+                  owners: List[str] = None,
+                  reverse=False) -> List:
+    if sections is not None:
+        index = 0
+        collection: List = sections
+    elif owners is not None:
+        index = 1
+        collection = owners
+    else:
+        raise ValueError('one of sections or owners is required')
+
+    l = get_priority_data()
+    m = [item for item in l if item[index] in collection]
+    n = sorted(m, key=lambda x: x[2], reverse=reverse)
+    o = [item[index] for item in n]
+    # sections are unhashable; use comprehension
+    missed = [j for j in collection if j not in o]
+    if missed:
+        Warn(f'No priority available for elements {missed}')
+
+    return o