localzone package

Submodules

localzone.context module

localzone.context

This module implements the methods for localzone context management.

copyright

  1. 2018 Andrew Grant Spencer

license

BSD, see LICENSE for more details.

localzone.context.load(filename, origin=None)[source]

Read a master zone file and construct a Zone object.

Parameters

  • filename (string) – The path to the zone’s master file.

  • origin (string) – (optional) The zone’s origin domain

Returns

Zone object

Return type

localzone.Zone

localzone.context.manage(filename, origin=None, autosave=False)[source]

A context manager that yields a Zone object.

Parameters

  • filename (string) – The path to the zone’s master file.

  • origin (string) – (optional) The zone’s origin domain

  • autosave (bool) – (optional) controls whether or not the zone’s master file is written to disk upon exit

Returns

Zone object

Return type

localzone.models.Zone

localzone.models module

localzone.models

This module contains the primary objects that power localzone.

copyright

  1. 2018 Andrew Grant Spencer

license

BSD, see LICENSE for more details.

class localzone.models.Record(origin, name, node, rdataset, rdata)[source]

Bases: object

Initialize a Record object.

Parameters

  • origin (dns.name.Name object) – The record’s parent domain.

  • name (dns.name.Name object) – The record’s name.

  • node (dns.node.Node object) – The record’s node.

  • rdataset (dns.rdataset.Rdataset object) – The record’s rdataset.

  • rdata (dns.rdata.Rdata object) – The record’s rdata.

property content
property hashid
property name
property node
property origin
property rdata
property rdataset
property rdclass
property rdtype
to_text()[source]
property ttl
class localzone.models.Zone(origin, rdclass=<RdataClass.IN: 1>, relativize=True)[source]

Bases: dns.zone.Zone

Initialize a Zone object.

The Zone class extends its base class dns.zone.Zone with additional abstractions (or denormalizations) for dealing with DNS zone records.

Parameters

  • origin (dns.name.Name object or string) – The zone’s origin.

  • rdclass (int) – The zone’s rdata class; the default is class dns.rdataclass.IN.

  • relativize (bool) – Should the zone’s names be relativized to the origin?

add_record(name, rdtype, content, rdclass='IN', ttl=None)[source]

Add a resource record to the zone.

Parameters

  • name (string) – The record’s name.

  • rdtype (string) – The record’s type, e.g. “CNAME”.

  • content (string) – The record’s content.

  • rdclass (string) – The record’s class.

  • ttl (ttl) – The record’s TTL.

Returns

Record object

Return type

localzone.models.Record

property filename
find_record(rdtype='ANY', name=None, content=None)[source]

Create and return a list of each resource record in the zone matching the search criteria.

Parameters

  • rdtype (string) – The record’s type.

  • name (string) – The record’s name.

  • content (string) – The record’s content.

Returns

list of Record objects

Return type

list

get_record(hashid)[source]

Get a resource record via ID. If no record is found, raise a KeyError.

Parameters

hashid (string) – The record’s ID.

Returns

Record object

Return type

localzone.models.Record

get_records(rdtype)[source]

Create and return a list of each resource record in the zone matching the specified type. If rdtype is “ANY”, all zone records are returned.

Parameters

rdtype (string) – The record’s type.

Returns

list of Record objects

Return type

list

nodes
origin
rdclass
property records

Return a list of Record objects for each resource record in the zone. If the zone is very large, be aware of memory constraints.

Returns

list of Record objects

Return type

list

relativize
remove_record(hashid, cascade=True)[source]

Remove a resource record from the zone. A KeyError is raised by the get_record() method if the supplied hashid is not found in the zone.

If cascade is True and the`rdataset` is empty after removing the record, the rdataset is also removed. If the node only contains the empty rdataset, then the node is removed.

Parameters

  • hashid (string) – The record’s ID.

  • cascade (bool) – (optional) Also remove the rdataset and node if empty?

save(filename=None, autoserial=True)[source]

Write the zone master file to disk. If filename is not provided, the file from which the zone was originally loaded will be written.

NB: this will replace the file located at filename.

Parameters

  • filename (string) – The location to where the zone master file will be written.

  • autoserial (bool) – Should the zone’s serial be updated automatically?

property soa

Return the SOA record of the zone’s origin.

Returns

Record object

Return type

localzone.models.Record

property ttl
update_record(hashid, content)[source]

Update the content of a resource record. A KeyError is raised by the get_record() method if the supplied hashid is not found in the zone.

Parameters

  • hashid (string) – The record’s ID.

  • content (string) – The new content of the record.

localzone.util module

localzone.util

This module contains general purpose utilities used by localzone.

localzone.util.checksum(word, size=32)[source]

Implements Fletcher’s checksum to create 16, 32, or 64-bit checksums.

Parameters

  • word (string) – The data to checksum.

  • size (int) – The checksum’s size.

Returns

Fletcher’s checksum represented as a hexadecimal digest.

Return type

string

localzone.util.group(iterable, n, padvalue=None)[source]

Create n-length sets from an iterable.

Parameters

  • iterable (iterable) – An iterable object.

  • n (int) – The number of items in the set.

  • padvalue – The value used, if necessary, to pad the last set.

Returns

An iterable set.

Return type

iterator

localzone.util.pack(tup)[source]

Packs a tuple of 8-bit integers.

Parameters

tup (tuple) – Tuple of 8-bit integers.

Returns

The packed n-bit value, where n is len(tup) * 8.

Return type

int

Module contents

The localzone DNS Library

A simple DNS library, written in Python, for managing zone files.

Basic usage:

>>> import localzone
>>> with localzone.manage("db.example.com") as z:
...     r = z.add_record("greeting", "TXT", "hello, world!")
...     r.name    # the record name, i.e. 'greeting'
...     r.rdtype  # the record type, i.e. 'TXT'
...     r.content # the record content, i.e. '"hello," "world!"'
...

Print the zone’s resource records:

>>> import localzone
>>> with localzone.manage("db.example.com") as z:
...     print(*z.records, sep="\n")
...
@ 3600 IN SOA ns username 2007120710 86400 7200 2419200 3600
@ 3600 IN NS ns
@ 3600 IN NS ns.somewhere.example.
@ 3600 IN MX 10 mail
@ ...

or:

>>> import localzone
>>> with localzone.manage("db.example.com") as z:
>>>     for r in z.records:
>>>         print(r)
...

The full documentation is available at <https://localzone.iomaestro.com>.

copyright

  1. 2018 by Andrew Grant Spencer.

license

BSD, see LICENSE for more details.