--- /dev/null
+# Copyright (C) 2001-2007, 2009, 2010 Nominum, Inc.
+#
+# Permission to use, copy, modify, and distribute this software and its
+# documentation for any purpose with or without fee is hereby granted,
+# provided that the above copyright notice and this permission notice
+# appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+"""DNS nodes. A node is a set of rdatasets."""
+
+import StringIO
+
+import dns.rdataset
+import dns.rdatatype
+import dns.renderer
+
+class Node(object):
+ """A DNS node.
+
+ A node is a set of rdatasets
+
+ @ivar rdatasets: the node's rdatasets
+ @type rdatasets: list of dns.rdataset.Rdataset objects"""
+
+ __slots__ = ['rdatasets']
+
+ def __init__(self):
+ """Initialize a DNS node.
+ """
+
+ self.rdatasets = [];
+
+ def to_text(self, name, **kw):
+ """Convert a node to text format.
+
+ Each rdataset at the node is printed. Any keyword arguments
+ to this method are passed on to the rdataset's to_text() method.
+ @param name: the owner name of the rdatasets
+ @type name: dns.name.Name object
+ @rtype: string
+ """
+
+ s = StringIO.StringIO()
+ for rds in self.rdatasets:
+ print >> s, rds.to_text(name, **kw)
+ return s.getvalue()[:-1]
+
+ def __repr__(self):
+ return '<DNS node ' + str(id(self)) + '>'
+
+ def __eq__(self, other):
+ """Two nodes are equal if they have the same rdatasets.
+
+ @rtype: bool
+ """
+ #
+ # This is inefficient. Good thing we don't need to do it much.
+ #
+ for rd in self.rdatasets:
+ if rd not in other.rdatasets:
+ return False
+ for rd in other.rdatasets:
+ if rd not in self.rdatasets:
+ return False
+ return True
+
+ def __ne__(self, other):
+ return not self.__eq__(other)
+
+ def __len__(self):
+ return len(self.rdatasets)
+
+ def __iter__(self):
+ return iter(self.rdatasets)
+
+ def find_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE,
+ create=False):
+ """Find an rdataset matching the specified properties in the
+ current node.
+
+ @param rdclass: The class of the rdataset
+ @type rdclass: int
+ @param rdtype: The type of the rdataset
+ @type rdtype: int
+ @param covers: The covered type. Usually this value is
+ dns.rdatatype.NONE, but if the rdtype is dns.rdatatype.SIG or
+ dns.rdatatype.RRSIG, then the covers value will be the rdata
+ type the SIG/RRSIG covers. The library treats the SIG and RRSIG
+ types as if they were a family of
+ types, e.g. RRSIG(A), RRSIG(NS), RRSIG(SOA). This makes RRSIGs much
+ easier to work with than if RRSIGs covering different rdata
+ types were aggregated into a single RRSIG rdataset.
+ @type covers: int
+ @param create: If True, create the rdataset if it is not found.
+ @type create: bool
+ @raises KeyError: An rdataset of the desired type and class does
+ not exist and I{create} is not True.
+ @rtype: dns.rdataset.Rdataset object
+ """
+
+ for rds in self.rdatasets:
+ if rds.match(rdclass, rdtype, covers):
+ return rds
+ if not create:
+ raise KeyError
+ rds = dns.rdataset.Rdataset(rdclass, rdtype)
+ self.rdatasets.append(rds)
+ return rds
+
+ def get_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE,
+ create=False):
+ """Get an rdataset matching the specified properties in the
+ current node.
+
+ None is returned if an rdataset of the specified type and
+ class does not exist and I{create} is not True.
+
+ @param rdclass: The class of the rdataset
+ @type rdclass: int
+ @param rdtype: The type of the rdataset
+ @type rdtype: int
+ @param covers: The covered type.
+ @type covers: int
+ @param create: If True, create the rdataset if it is not found.
+ @type create: bool
+ @rtype: dns.rdataset.Rdataset object or None
+ """
+
+ try:
+ rds = self.find_rdataset(rdclass, rdtype, covers, create)
+ except KeyError:
+ rds = None
+ return rds
+
+ def delete_rdataset(self, rdclass, rdtype, covers=dns.rdatatype.NONE):
+ """Delete the rdataset matching the specified properties in the
+ current node.
+
+ If a matching rdataset does not exist, it is not an error.
+
+ @param rdclass: The class of the rdataset
+ @type rdclass: int
+ @param rdtype: The type of the rdataset
+ @type rdtype: int
+ @param covers: The covered type.
+ @type covers: int
+ """
+
+ rds = self.get_rdataset(rdclass, rdtype, covers)
+ if not rds is None:
+ self.rdatasets.remove(rds)
+
+ def replace_rdataset(self, replacement):
+ """Replace an rdataset.
+
+ It is not an error if there is no rdataset matching I{replacement}.
+
+ Ownership of the I{replacement} object is transferred to the node;
+ in other words, this method does not store a copy of I{replacement}
+ at the node, it stores I{replacement} itself.
+ """
+
+ self.delete_rdataset(replacement.rdclass, replacement.rdtype,
+ replacement.covers)
+ self.rdatasets.append(replacement)
git.samba.org / idra / samba.git / blobdiff