Source code for pytomo.dns.rrset

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"""DNS RRsets (an RRset is a named rdataset)"""

from __future__ import absolute_import

from . import name as dns_name
from . import rdata as dns_rdata
from . import rdataset as dns_rdataset
from . import rdatatype as dns_rdatatype
from . import rdataclass as dns_rdataclass
#from . import renderer as dns_renderer

[docs]class RRset(dns_rdataset.Rdataset): """A DNS RRset (named rdataset). RRset inherits from Rdataset, and RRsets can be treated as Rdatasets in most cases. There are, however, a few notable exceptions. RRsets have different to_wire() and to_text() method arguments, reflecting the fact that RRsets always have an owner name. """ __slots__ = ['name', 'deleting'] def __init__(self, name, rdclass, rdtype, covers=dns_rdatatype.NONE, deleting=None): """Create a new RRset.""" super(RRset, self).__init__(rdclass, rdtype, covers) self.name = name self.deleting = deleting def _clone(self): obj = super(RRset, self)._clone() obj.name = self.name obj.deleting = self.deleting return obj def __repr__(self): if self.covers == 0: ctext = '' else: ctext = '(' + dns_rdatatype.to_text(self.covers) + ')' if not self.deleting is None: dtext = ' delete=' + dns_rdataclass.to_text(self.deleting) else: dtext = '' return '<DNS ' + str(self.name) + ' ' + \ dns_rdataclass.to_text(self.rdclass) + ' ' + \ dns_rdatatype.to_text(self.rdtype) + ctext + dtext + ' RRset>' def __str__(self): return self.to_text() def __eq__(self, other): """Two RRsets are equal if they have the same name and the same rdataset @rtype: bool""" if not isinstance(other, RRset): return False if self.name != other.name: return False return super(RRset, self).__eq__(other)
[docs] def match(self, name, rdclass, rdtype, covers, deleting=None): """Returns True if this rrset matches the specified class, type, covers, and deletion state.""" if not super(RRset, self).match(rdclass, rdtype, covers): return False if self.name != name or self.deleting != deleting: return False return True
[docs] def to_text(self, origin=None, relativize=True, **kw): """Convert the RRset into DNS master file format. @see: L{dns_name.Name.choose_relativity} for more information on how I{origin} and I{relativize} determine the way names are emitted. Any additional keyword arguments are passed on to the rdata to_text() method. @param origin: The origin for relative names, or None. @type origin: dns_name.Name object @param relativize: True if names should names be relativized @type relativize: bool""" return super(RRset, self).to_text(self.name, origin, relativize, self.deleting, **kw)
[docs] def to_wire(self, file, compress=None, origin=None, **kw): """Convert the RRset to wire format.""" return super(RRset, self).to_wire(self.name, file, compress, origin, self.deleting, **kw)
[docs] def to_rdataset(self): """Convert an RRset into an Rdataset. @rtype: dns_rdataset.Rdataset object """ return dns_rdataset.from_rdata_list(self.ttl, list(self))
[docs]def from_text_list(name, ttl, rdclass, rdtype, text_rdatas): """Create an RRset with the specified name, TTL, class, and type, and with the specified list of rdatas in text format. @rtype: dns_rrset.RRset object """ if isinstance(name, (str, unicode)): name = dns_name.from_text(name, None) if isinstance(rdclass, (str, unicode)): rdclass = dns_rdataclass.from_text(rdclass) if isinstance(rdtype, (str, unicode)): rdtype = dns_rdatatype.from_text(rdtype) r = RRset(name, rdclass, rdtype) r.update_ttl(ttl) for t in text_rdatas: rd = dns_rdata.from_text(r.rdclass, r.rdtype, t) r.add(rd) return r
[docs]def from_text(name, ttl, rdclass, rdtype, *text_rdatas): """Create an RRset with the specified name, TTL, class, and type and with the specified rdatas in text format. @rtype: dns_rrset.RRset object """ return from_text_list(name, ttl, rdclass, rdtype, text_rdatas)
[docs]def from_rdata_list(name, ttl, rdatas): """Create an RRset with the specified name and TTL, and with the specified list of rdata objects. @rtype: dns_rrset.RRset object """ if isinstance(name, (str, unicode)): name = dns_name.from_text(name, None) if len(rdatas) == 0: raise ValueError("rdata list must not be empty") r = None for rd in rdatas: if r is None: r = RRset(name, rd.rdclass, rd.rdtype) r.update_ttl(ttl) first_time = False r.add(rd) return r
[docs]def from_rdata(name, ttl, *rdatas): """Create an RRset with the specified name and TTL, and with the specified rdata objects. @rtype: dns_rrset.RRset object """ return from_rdata_list(name, ttl, rdatas)