Source code for dns.rrset

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

from typing import Any, cast, Collection, Dict, Optional, Union

import dns.name
import dns.rdataset
import dns.rdataclass
import 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: dns.name.Name, rdclass: dns.rdataclass.RdataClass, rdtype: dns.rdatatype.RdataType, covers: dns.rdatatype.RdataType = dns.rdatatype.NONE, deleting: Optional[dns.rdataclass.RdataClass] = None, ): """Create a new RRset.""" super().__init__(rdclass, rdtype, covers) self.name = name self.deleting = deleting def _clone(self): obj = super()._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 self.deleting is not 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: " + self._rdata_repr() + ">" ) def __str__(self): return self.to_text() def __eq__(self, other): if isinstance(other, RRset): if self.name != other.name: return False elif not isinstance(other, dns.rdataset.Rdataset): return False return super().__eq__(other)
[docs] def match(self, *args: Any, **kwargs: Any) -> bool: # type: ignore[override] """Does this rrset match the specified attributes? Behaves as :py:func:`full_match()` if the first argument is a ``dns.name.Name``, and as :py:func:`dns.rdataset.Rdataset.match()` otherwise. (This behavior fixes a design mistake where the signature of this method became incompatible with that of its superclass. The fix makes RRsets matchable as Rdatasets while preserving backwards compatibility.) """ if isinstance(args[0], dns.name.Name): return self.full_match(*args, **kwargs) # type: ignore[arg-type] else: return super().match(*args, **kwargs) # type: ignore[arg-type]
[docs] def full_match( self, name: dns.name.Name, rdclass: dns.rdataclass.RdataClass, rdtype: dns.rdatatype.RdataType, covers: dns.rdatatype.RdataType, deleting: Optional[dns.rdataclass.RdataClass] = None, ) -> bool: """Returns ``True`` if this rrset matches the specified name, class, type, covers, and deletion state. """ if not super().match(rdclass, rdtype, covers): return False if self.name != name or self.deleting != deleting: return False return True
# pylint: disable=arguments-differ
[docs] def to_text( # type: ignore[override] self, origin: Optional[dns.name.Name] = None, relativize: bool = True, **kw: Dict[str, Any] ) -> str: """Convert the RRset into DNS zone file format. See ``dns.name.Name.choose_relativity`` for more information on how *origin* and *relativize* determine the way names are emitted. Any additional keyword arguments are passed on to the rdata ``to_text()`` method. *origin*, a ``dns.name.Name`` or ``None``, the origin for relative names. *relativize*, a ``bool``. If ``True``, names will be relativized to *origin*. """ return super().to_text( self.name, origin, relativize, self.deleting, **kw # type: ignore )
[docs] def to_wire( # type: ignore[override] self, file: Any, compress: Optional[dns.name.CompressType] = None, # type: ignore origin: Optional[dns.name.Name] = None, **kw: Dict[str, Any] ) -> int: """Convert the RRset to wire format. All keyword arguments are passed to ``dns.rdataset.to_wire()``; see that function for details. Returns an ``int``, the number of records emitted. """ return super().to_wire( self.name, file, compress, origin, self.deleting, **kw # type:ignore )
# pylint: enable=arguments-differ
[docs] def to_rdataset(self) -> dns.rdataset.Rdataset: """Convert an RRset into an Rdataset. Returns a ``dns.rdataset.Rdataset``. """ return dns.rdataset.from_rdata_list(self.ttl, list(self))
[docs]def from_text_list( name: Union[dns.name.Name, str], ttl: int, rdclass: Union[dns.rdataclass.RdataClass, str], rdtype: Union[dns.rdatatype.RdataType, str], text_rdatas: Collection[str], idna_codec: Optional[dns.name.IDNACodec] = None, origin: Optional[dns.name.Name] = None, relativize: bool = True, relativize_to: Optional[dns.name.Name] = None, ) -> RRset: """Create an RRset with the specified name, TTL, class, and type, and with the specified list of rdatas in text format. *idna_codec*, a ``dns.name.IDNACodec``, specifies the IDNA encoder/decoder to use; if ``None``, the default IDNA 2003 encoder/decoder is used. *origin*, a ``dns.name.Name`` (or ``None``), the origin to use for relative names. *relativize*, a ``bool``. If true, name will be relativized. *relativize_to*, a ``dns.name.Name`` (or ``None``), the origin to use when relativizing names. If not set, the *origin* value will be used. Returns a ``dns.rrset.RRset`` object. """ if isinstance(name, str): name = dns.name.from_text(name, None, idna_codec=idna_codec) the_rdclass = dns.rdataclass.RdataClass.make(rdclass) the_rdtype = dns.rdatatype.RdataType.make(rdtype) r = RRset(name, the_rdclass, the_rdtype) r.update_ttl(ttl) for t in text_rdatas: rd = dns.rdata.from_text( r.rdclass, r.rdtype, t, origin, relativize, relativize_to, idna_codec ) r.add(rd) return r
[docs]def from_text( name: Union[dns.name.Name, str], ttl: int, rdclass: Union[dns.rdataclass.RdataClass, str], rdtype: Union[dns.rdatatype.RdataType, str], *text_rdatas: Any ) -> RRset: """Create an RRset with the specified name, TTL, class, and type and with the specified rdatas in text format. Returns a ``dns.rrset.RRset`` object. """ return from_text_list( name, ttl, rdclass, rdtype, cast(Collection[str], text_rdatas) )
[docs]def from_rdata_list( name: Union[dns.name.Name, str], ttl: int, rdatas: Collection[dns.rdata.Rdata], idna_codec: Optional[dns.name.IDNACodec] = None, ) -> RRset: """Create an RRset with the specified name and TTL, and with the specified list of rdata objects. *idna_codec*, a ``dns.name.IDNACodec``, specifies the IDNA encoder/decoder to use; if ``None``, the default IDNA 2003 encoder/decoder is used. Returns a ``dns.rrset.RRset`` object. """ if isinstance(name, str): name = dns.name.from_text(name, None, idna_codec=idna_codec) 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) r.add(rd) assert r is not None return r
[docs]def from_rdata(name: Union[dns.name.Name, str], ttl: int, *rdatas: Any) -> RRset: """Create an RRset with the specified name and TTL, and with the specified rdata objects. Returns a ``dns.rrset.RRset`` object. """ return from_rdata_list(name, ttl, cast(Collection[dns.rdata.Rdata], rdatas))