Issue #14814: reorganize ipaddress documentation and document all attributes of IPv[46]Address objects

This commit is contained in:
Eli Bendersky 2012-07-31 17:23:11 +03:00
parent 336d9ac6bd
commit 0e49749f31
1 changed files with 192 additions and 56 deletions

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@ -22,19 +22,18 @@ subnet, as well as checking whether or not a string represents a valid
IP address or network definition.
Defining IP Addresses and Interfaces
------------------------------------
Convenience factory functions
-----------------------------
The :mod:`ipaddress` module provides factory functions to define IP addresses
and networks:
The :mod:`ipaddress` module provides factory functions to conveniently create
IP addresses, networks and interfaces:
.. function:: ip_address(address)
Return an :class:`IPv4Address` or :class:`IPv6Address` object depending on
the IP address passed as argument. *address* is a string or integer
representing the IP address. Either IPv4 or IPv6 addresses may be supplied;
integers less than 2**32 will be considered to be IPv4 by default. A
:exc:`ValueError` is raised if the *address* passed is neither an IPv4 nor
the IP address passed as argument. Either IPv4 or IPv6 addresses may be
supplied; integers less than 2**32 will be considered to be IPv4 by default.
A :exc:`ValueError` is raised if *address* does not represent a valid IPv4 or
IPv6 address.
>>> ipaddress.ip_address('192.168.0.1')
@ -50,8 +49,8 @@ and networks:
representing the IP network. Either IPv4 or IPv6 networks may be supplied;
integers less than 2**32 will be considered to be IPv4 by default. *strict*
is passed to :class:`IPv4Network` or :class:`IPv6Network` constructor. A
:exc:`ValueError` is raised if the string passed isn't either an IPv4 or IPv6
address, or if the network has host bits set.
:exc:`ValueError` is raised if *address* does not represent a valid IPv4 or
IPv6 address, or if the network has host bits set.
>>> ipaddress.ip_network('192.168.0.0/28')
IPv4Network('192.168.0.0/28')
@ -62,45 +61,174 @@ and networks:
Return an :class:`IPv4Interface` or :class:`IPv6Interface` object depending
on the IP address passed as argument. *address* is a string or integer
representing the IP address. Either IPv4 or IPv6 addresses may be supplied;
integers less than 2**32 will be considered to be IPv4 by default.. A
:exc:`ValueError` is raised if the *address* passed isn't either an IPv4 or
integers less than 2**32 will be considered to be IPv4 by default. A
:exc:`ValueError` is raised if *address* does not represent a valid IPv4 or
IPv6 address.
Representing IP Addresses and Networks
--------------------------------------
Address objects
---------------
The module defines the following and classes to represent IP addresses
and networks:
.. todo: list the properties and methods
The :class:`IPv4Address` and :class:`IPv6Address` objects share a lot of common
attributes. Some attributes that are only meaningful for IPv6 addresses are
also implemented by :class:`IPv4Address` objects, in order to make it easier to
write code that handles both IP versions correctly. To avoid duplication, all
common attributes will only be documented for :class:`IPv4Address`.
.. class:: IPv4Address(address)
Construct an IPv4 address. *address* is a string or integer representing the
IP address. An :exc:`AddressValueError` is raised if *address* is not a
valid IPv4 address.
Construct an IPv4 address. An :exc:`AddressValueError` is raised if
*address* is not a valid IPv4 address.
The following constitutes a valid IPv4 address:
1. A string in decimal-dot notation, consisting of four decimal integers in
the inclusive range 0-255, separated by dots (e.g. ``192.168.0.1``). Each
integer represents an octet (byte) in the address, big-endian.
2. An integer that fits into 32 bits.
3. An integer packed into a :class:`bytes` object of length 4, big-endian.
>>> ipaddress.IPv4Address('192.168.0.1')
IPv4Address('192.168.0.1')
>>> ipaddress.IPv4Address('192.0.2.1') == ipaddress.IPv4Address(3221225985)
True
.. attribute:: exploded
.. class:: IPv4Interface(address)
The longhand version of the address as a string. Note: the
exploded/compressed distinction is meaningful only for IPv6 addresses.
For IPv4 addresses it is the same.
Construct an IPv4 interface. *address* is a string or integer representing
the IP interface. An :exc:`AddressValueError` is raised if *address* is not
a valid IPv4 address.
.. attribute:: compressed
The network address for the interface is determined by calling
``IPv4Network(address, strict=False)``.
The shorthand version of the address as a string.
>>> ipaddress.IPv4Interface('192.168.0.0/24')
IPv4Interface('192.168.0.0/24')
>>> ipaddress.IPv4Interface('192.168.0.0/24').network
IPv4Network('192.168.0.0/24')
.. attribute:: packed
The binary representation of this address - a :class:`bytes` object.
.. attribute:: version
A numeric version number.
.. attribute:: max_prefixlen
Maximal length of the prefix (in bits). The prefix defines the number of
leading bits in an address that are compared to determine whether or not an
address is part of a network.
.. attribute:: is_multicast
``True`` if the address is reserved for multicast use. See :RFC:`3171` (for
IPv4) or :RFC:`2373` (for IPv6).
.. attribute:: is_private
``True`` if the address is allocated for private networks. See :RFC:`1918`
(for IPv4) or :RFC:`4193` (for IPv6).
.. attribute:: is_unspecified
``True`` if the address is unspecified. See :RFC:`5375` (for IPv4) or
:RFC:`2373` (for IPv6).
.. attribute:: is_reserved
``True`` if the address is otherwise IETF reserved.
.. attribute:: is_loopback
``True`` if this is a loopback address. See :RFC:`3330` (for IPv4) or
:RFC:`2373` (for IPv6).
.. attribute:: is_link_local
``True`` if the address is reserved for link-local. See :RFC:`3927`.
.. class:: IPv6Address(address)
Construct an IPv6 address. An :exc:`AddressValueError` is raised if
*address* is not a valid IPv6 address.
The following constitutes a valid IPv6 address:
1. A string consisting of eight groups of four hexadecimal digits, each
group representing 16 bits. The groups are separated by colons.
This describes an *exploded* (longhand) notation. The string can
also be *compressed* (shorthand notation) by various means. See
:RFC:`4291` for details. For example,
``"0000:0000:0000:0000:0000:0abc:0007:0def"`` can be compressed to
``"::abc:7:def"``.
2. An integer that fits into 128 bits.
3. An integer packed into a :class:`bytes` object of length 16, big-endian.
>>> ipaddress.IPv6Address('2001:db8::1000')
IPv6Address('2001:db8::1000')
All the attributes exposed by :class:`IPv4Address` are supported. In
addition, the following attributs are exposed only by :class:`IPv6Address`.
.. attribute:: is_site_local
``True`` if the address is reserved for site-local. Note that the site-local
address space has been deprecated by :RFC:`3879`. Use
:attr:`~IPv4Address.is_private` to test if this address is in the space of
unique local addresses as defined by :RFC:`4193`.
.. attribute:: ipv4_mapped
If this address represents a IPv4 mapped address, return the IPv4 mapped
address. Otherwise return ``None``.
.. attribute:: teredo
If this address appears to be a teredo address (starts with ``2001::/32``),
return a tuple of embedded teredo IPs ``(server, client)`` pairs. Otherwise
return ``None``.
.. attribute:: sixtofour
If this address appears to contain a 6to4 embedded address, return the
embedded IPv4 address. Otherwise return ``None``.
Operators
^^^^^^^^^
Address objects support some operators. Unless stated otherwise, operators can
only be applied between compatible objects (i.e. IPv4 with IPv4, IPv6 with
IPv6).
Logical operators
"""""""""""""""""
Address objects can be compared with the usual set of logical operators. Some
examples::
>>> IPv4Address('127.0.0.2') > IPv4Address('127.0.0.1')
True
>>> IPv4Address('127.0.0.2') == IPv4Address('127.0.0.1')
False
>>> IPv4Address('127.0.0.2') != IPv4Address('127.0.0.1')
True
Arithmetic operators
""""""""""""""""""""
Integers can be added to or subtracted from address objects. Some examples::
>>> IPv4Address('127.0.0.2') + 3
IPv4Address('127.0.0.5')
>>> IPv4Address('127.0.0.2') - 3
IPv4Address('126.255.255.255')
>>> IPv4Address('255.255.255.255') + 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ipaddress.AddressValueError: 4294967296 (>= 2**32) is not permitted as an IPv4 address
Network objects
---------------
.. class:: IPv4Network(address, strict=True)
@ -121,31 +249,6 @@ and networks:
IPv4Network('192.0.2.0/27')
.. class:: IPv6Address(address)
Construct an IPv6 address. *address* is a string or integer representing the
IP address. An :exc:`AddressValueError` is raised if *address* is not a
valid IPv6 address.
>>> ipaddress.IPv6Address('2001:db8::1000')
IPv6Address('2001:db8::1000')
.. class:: IPv6Interface(address)
Construct an IPv6 interface. *address* is a string or integer representing
the IP interface. An :exc:`AddressValueError` is raised if *address* is not
a valid IPv6 address.
The network address for the interface is determined by calling
``IPv6Network(address, strict=False)``.
>>> ipaddress.IPv6Interface('2001:db8::1000/96')
IPv6Interface('2001:db8::1000/96')
>>> ipaddress.IPv6Interface('2001:db8::1000/96').network
IPv6Network('2001:db8::/96')
.. class:: IPv6Network(address, strict=True)
Construct an IPv6 network. *address* is a string or integer representing the
@ -165,6 +268,39 @@ and networks:
IPv6Network('2001:db8::/96')
Interface objects
-----------------
.. class:: IPv4Interface(address)
Construct an IPv4 interface. *address* is a string or integer representing
the IP interface. An :exc:`AddressValueError` is raised if *address* is not
a valid IPv4 address.
The network address for the interface is determined by calling
``IPv4Network(address, strict=False)``.
>>> ipaddress.IPv4Interface('192.168.0.0/24')
IPv4Interface('192.168.0.0/24')
>>> ipaddress.IPv4Interface('192.168.0.0/24').network
IPv4Network('192.168.0.0/24')
.. class:: IPv6Interface(address)
Construct an IPv6 interface. *address* is a string or integer representing
the IP interface. An :exc:`AddressValueError` is raised if *address* is not
a valid IPv6 address.
The network address for the interface is determined by calling
``IPv6Network(address, strict=False)``.
>>> ipaddress.IPv6Interface('2001:db8::1000/96')
IPv6Interface('2001:db8::1000/96')
>>> ipaddress.IPv6Interface('2001:db8::1000/96').network
IPv6Network('2001:db8::/96')
Other Module Level Functions
----------------------------