util: Add accessory functions for editing config

1 files changed, 28 insertions, 1 deletions

diff --git a/ncserver/base/util.py b/ncserver/base/util.py
index 3df076c..f69c65b 100644
--- a/ncserver/base/util.py
+++ b/ncserver/base/util.py
@@ -11,8 +11,35 @@ SPDX-License-Identifier: NCSA
 """
 
 
-def _(the_string):
+from netconf import error
+
+
+def _(the_string: str) -> str:
     """Translate a user-facing string.
 
     Currently not implemented, but allows us to implement translation later."""
     return the_string
+
+
+def ensure_leaf(rpc, node):
+    """Ensure that the node is a leaf (contains no child nodes)."""
+    if len(node) > 0:
+        raise error.UnknownElementAppError(rpc, node[0])
+
+
+def node_operation(node, def_op='merge') -> str:
+    """Determine the operation desired for an XML node.
+
+    :param node:
+        The node.
+
+    :param str def_op:
+        The default operation if none is specified.  Defaults to 'merge'.
+
+    :returns str:
+        The operation desired.
+    """
+
+    nc10 = '{urn:ietf:params:xml:ns:netconf:base:1.0}operation'
+    nc11 = '{urn:ietf:params:xml:ns:netconf:base:1.1}operation'
+    return node.attrib.get(nc11, node.attrib.get(nc10, def_op))