Transaction support.

1 files changed, 30 insertions, 0 deletions

diff --git a/dns/node.py b/dns/node.py
index b7e21b5..8e1451f 100644
--- a/dns/node.py
+++ b/dns/node.py
@@ -183,3 +183,33 @@ class Node:
         self.delete_rdataset(replacement.rdclass, replacement.rdtype,
                              replacement.covers)
         self.rdatasets.append(replacement)
+
+
+@dns.immutable.immutable
+class ImmutableNode(Node):
+
+    """An ImmutableNode is an immutable set of rdatasets."""
+
+    def __init__(self, node):
+        super().__init__()
+        self.rdatasets = tuple(
+            [dns.rdataset.ImmutableRdataset(rds) for rds in node.rdatasets]
+        )
+
+    def find_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE,
+                      create=False):
+        if create:
+            raise TypeError("immutable")
+        return super().find_rdataset(rdclass, rdtype, covers, False)
+
+    def get_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE,
+                     create=False):
+        if create:
+            raise TypeError("immutable")
+        return super().get_rdataset(rdclass, rdtype, covers, False)
+
+    def delete_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE):
+        raise TypeError("immutable")
+
+    def replace_rdataset(self, replacement):
+        raise TypeError("immutable")