netwatch.py/netaddr-0.7.10/netaddr/tests/2.x/ip/sets.txt

First of all you need to pull the various netaddr classes and functions into your namespace.

.. note:: Do this for the purpose of this tutorial only. In your own code, you should be explicit about the classes, functions and constants you import to avoid name clashes.

>>> from netaddr import *

----------------
Creating IP sets
----------------

Here how to create IP sets.

An empty set.

>>> IPSet()
IPSet([])
>>> IPSet([])
IPSet([])

You can specific either IP addresses and networks as strings, or as `IPAddress` or `IPNetwork` objects.

>>> IPSet(['192.0.2.0'])
IPSet(['192.0.2.0/32'])
>>> IPSet([IPAddress('192.0.2.0')])
IPSet(['192.0.2.0/32'])
>>> IPSet([IPNetwork('192.0.2.0')])
IPSet(['192.0.2.0/32'])
>>> IPSet([IPNetwork('192.0.2.0/24')])
IPSet(['192.0.2.0/24'])

You can interate over all the IP addresses that are members of IP set.

>>> for ip in IPSet(['192.0.2.0/28', '::192.0.2.0/124']):
...     print ip
192.0.2.0
192.0.2.1
192.0.2.2
192.0.2.3
192.0.2.4
192.0.2.5
192.0.2.6
192.0.2.7
192.0.2.8
192.0.2.9
192.0.2.10
192.0.2.11
192.0.2.12
192.0.2.13
192.0.2.14
192.0.2.15
::192.0.2.0
::192.0.2.1
::192.0.2.2
::192.0.2.3
::192.0.2.4
::192.0.2.5
::192.0.2.6
::192.0.2.7
::192.0.2.8
::192.0.2.9
::192.0.2.10
::192.0.2.11
::192.0.2.12
::192.0.2.13
::192.0.2.14
::192.0.2.15

--------------------------------
Adding and removing set elements
--------------------------------

>>> s1 = IPSet()
>>> s1.add('192.0.2.0')
>>> s1
IPSet(['192.0.2.0/32'])
>>> s1.remove('192.0.2.0')
>>> s1
IPSet([])

--------------
Set membership
--------------

Here is a simple arbitrary IP address range.

>>> iprange = IPRange('192.0.1.255', '192.0.2.16')

We can see the CIDR networks that can existing with this defined range.

>>> iprange.cidrs()
[IPNetwork('192.0.1.255/32'), IPNetwork('192.0.2.0/28'), IPNetwork('192.0.2.16/32')]

Here's an IP set.

>>> ipset = IPSet(['192.0.2.0/28'])

Now, let's iterate over the IP addresses in the arbitrary IP address range and see if they are found within the IP set.

>>> for ip in iprange:
...     print ip, ip in ipset
192.0.1.255 False
192.0.2.0 True
192.0.2.1 True
192.0.2.2 True
192.0.2.3 True
192.0.2.4 True
192.0.2.5 True
192.0.2.6 True
192.0.2.7 True
192.0.2.8 True
192.0.2.9 True
192.0.2.10 True
192.0.2.11 True
192.0.2.12 True
192.0.2.13 True
192.0.2.14 True
192.0.2.15 True
192.0.2.16 False

-------------------------------------
Unions, intersections and differences
-------------------------------------

Here are some examples of union operations performed on `IPSet` objects.

>>> IPSet(['192.0.2.0'])
IPSet(['192.0.2.0/32'])

>>> IPSet(['192.0.2.0']) | IPSet(['192.0.2.1'])
IPSet(['192.0.2.0/31'])

>>> IPSet(['192.0.2.0']) | IPSet(['192.0.2.1']) | IPSet(['192.0.2.3'])
IPSet(['192.0.2.0/31', '192.0.2.3/32'])

>>> IPSet(['192.0.2.0']) | IPSet(['192.0.2.1']) | IPSet(['192.0.2.3/30'])
IPSet(['192.0.2.0/30'])

>>> IPSet(['192.0.2.0']) | IPSet(['192.0.2.1']) | IPSet(['192.0.2.3/31'])
IPSet(['192.0.2.0/30'])

>>> IPSet(['192.0.2.0/24']) | IPSet(['192.0.3.0/24']) | IPSet(['192.0.4.0/24'])
IPSet(['192.0.2.0/23', '192.0.4.0/24'])

Here is an example of the union, intersection and symmetric difference operations all in play at the same time.

>>> adj_cidrs = list(IPNetwork('192.0.2.0/24').subnet(28))
>>> even_cidrs = adj_cidrs[::2]
>>> evens = IPSet(even_cidrs)
>>> evens
IPSet(['192.0.2.0/28', '192.0.2.32/28', '192.0.2.64/28', '192.0.2.96/28', '192.0.2.128/28', '192.0.2.160/28', '192.0.2.192/28', '192.0.2.224/28'])
>>> IPSet(['192.0.2.0/24']) & evens
IPSet(['192.0.2.0/28', '192.0.2.32/28', '192.0.2.64/28', '192.0.2.96/28', '192.0.2.128/28', '192.0.2.160/28', '192.0.2.192/28', '192.0.2.224/28'])
>>> odds = IPSet(['192.0.2.0/24']) ^ evens
>>> odds
IPSet(['192.0.2.16/28', '192.0.2.48/28', '192.0.2.80/28', '192.0.2.112/28', '192.0.2.144/28', '192.0.2.176/28', '192.0.2.208/28', '192.0.2.240/28'])
>>> evens | odds
IPSet(['192.0.2.0/24'])
>>> evens & odds
IPSet([])
>>> evens ^ odds
IPSet(['192.0.2.0/24'])

---------------------
Supersets and subsets
---------------------

IP sets provide the ability to test whether a group of addresses ranges fit within the set of another group of address ranges.

>>> s1 = IPSet(['192.0.2.0/24', '192.0.4.0/24'])
>>> s2 = IPSet(['192.0.2.0', '192.0.4.0'])
>>> s1
IPSet(['192.0.2.0/24', '192.0.4.0/24'])
>>> s2
IPSet(['192.0.2.0/32', '192.0.4.0/32'])
>>> s1.issuperset(s2)
True
>>> s2.issubset(s1)
True
>>> s2.issuperset(s1)
False
>>> s1.issubset(s2)
False

Here's a more complete example using various well known IPv4 address ranges.

>>> ipv4_addr_space = IPSet(['0.0.0.0/0'])
>>> private = IPSet(['10.0.0.0/8', '172.16.0.0/12', '192.0.2.0/24', '192.168.0.0/16', '239.192.0.0/14'])
>>> reserved = IPSet(['225.0.0.0/8', '226.0.0.0/7', '228.0.0.0/6', '234.0.0.0/7', '236.0.0.0/7', '238.0.0.0/8', '240.0.0.0/4'])
>>> unavailable = reserved | private
>>> available = ipv4_addr_space ^ unavailable

Let's see what we've got:

>>> for cidr in available.iter_cidrs():
...     print cidr, cidr[0], cidr[-1]
0.0.0.0/5 0.0.0.0 7.255.255.255
8.0.0.0/7 8.0.0.0 9.255.255.255
11.0.0.0/8 11.0.0.0 11.255.255.255
12.0.0.0/6 12.0.0.0 15.255.255.255
16.0.0.0/4 16.0.0.0 31.255.255.255
32.0.0.0/3 32.0.0.0 63.255.255.255
64.0.0.0/2 64.0.0.0 127.255.255.255
128.0.0.0/3 128.0.0.0 159.255.255.255
160.0.0.0/5 160.0.0.0 167.255.255.255
168.0.0.0/6 168.0.0.0 171.255.255.255
172.0.0.0/12 172.0.0.0 172.15.255.255
172.32.0.0/11 172.32.0.0 172.63.255.255
172.64.0.0/10 172.64.0.0 172.127.255.255
172.128.0.0/9 172.128.0.0 172.255.255.255
173.0.0.0/8 173.0.0.0 173.255.255.255
174.0.0.0/7 174.0.0.0 175.255.255.255
176.0.0.0/4 176.0.0.0 191.255.255.255
192.0.0.0/23 192.0.0.0 192.0.1.255
192.0.3.0/24 192.0.3.0 192.0.3.255
192.0.4.0/22 192.0.4.0 192.0.7.255
192.0.8.0/21 192.0.8.0 192.0.15.255
192.0.16.0/20 192.0.16.0 192.0.31.255
192.0.32.0/19 192.0.32.0 192.0.63.255
192.0.64.0/18 192.0.64.0 192.0.127.255
192.0.128.0/17 192.0.128.0 192.0.255.255
192.1.0.0/16 192.1.0.0 192.1.255.255
192.2.0.0/15 192.2.0.0 192.3.255.255
192.4.0.0/14 192.4.0.0 192.7.255.255
192.8.0.0/13 192.8.0.0 192.15.255.255
192.16.0.0/12 192.16.0.0 192.31.255.255
192.32.0.0/11 192.32.0.0 192.63.255.255
192.64.0.0/10 192.64.0.0 192.127.255.255
192.128.0.0/11 192.128.0.0 192.159.255.255
192.160.0.0/13 192.160.0.0 192.167.255.255
192.169.0.0/16 192.169.0.0 192.169.255.255
192.170.0.0/15 192.170.0.0 192.171.255.255
192.172.0.0/14 192.172.0.0 192.175.255.255
192.176.0.0/12 192.176.0.0 192.191.255.255
192.192.0.0/10 192.192.0.0 192.255.255.255
193.0.0.0/8 193.0.0.0 193.255.255.255
194.0.0.0/7 194.0.0.0 195.255.255.255
196.0.0.0/6 196.0.0.0 199.255.255.255
200.0.0.0/5 200.0.0.0 207.255.255.255
208.0.0.0/4 208.0.0.0 223.255.255.255
224.0.0.0/8 224.0.0.0 224.255.255.255
232.0.0.0/7 232.0.0.0 233.255.255.255
239.0.0.0/9 239.0.0.0 239.127.255.255
239.128.0.0/10 239.128.0.0 239.191.255.255
239.196.0.0/14 239.196.0.0 239.199.255.255
239.200.0.0/13 239.200.0.0 239.207.255.255
239.208.0.0/12 239.208.0.0 239.223.255.255
239.224.0.0/11 239.224.0.0 239.255.255.255

>>> ipv4_addr_space ^ available
IPSet(['10.0.0.0/8', '172.16.0.0/12', '192.0.2.0/24', '192.168.0.0/16', '225.0.0.0/8', '226.0.0.0/7', '228.0.0.0/6', '234.0.0.0/7', '236.0.0.0/7', '238.0.0.0/8', '239.192.0.0/14', '240.0.0.0/4'])


------------------------------
Combined IPv4 and IPv6 support
------------------------------

In keeping with netaddr's pragmatic approach, you are free to mix and match IPv4 and IPv6 within the same data structure.

>>> s1 = IPSet(['192.0.2.0', '::192.0.2.0', '192.0.2.2', '::192.0.2.2'])
>>> s2 = IPSet(['192.0.2.2', '::192.0.2.2', '192.0.2.4', '::192.0.2.4'])
>>> s1
IPSet(['192.0.2.0/32', '192.0.2.2/32', '::192.0.2.0/128', '::192.0.2.2/128'])
>>> s2
IPSet(['192.0.2.2/32', '192.0.2.4/32', '::192.0.2.2/128', '::192.0.2.4/128'])

^^^^^^^^^^^^^^^^^^^^^^^
IPv4 and IPv6 set union
^^^^^^^^^^^^^^^^^^^^^^^

>>> s1 | s2
IPSet(['192.0.2.0/32', '192.0.2.2/32', '192.0.2.4/32', '::192.0.2.0/128', '::192.0.2.2/128', '::192.0.2.4/128'])

^^^^^^^^^^^^^^^^
set intersection
^^^^^^^^^^^^^^^^

>>> s1 & s2
IPSet(['192.0.2.2/32', '::192.0.2.2/128'])

^^^^^^^^^^^^^^
set difference
^^^^^^^^^^^^^^

>>> s1 - s2
IPSet(['192.0.2.0/32', '::192.0.2.0/128'])
>>> s2 - s1
IPSet(['192.0.2.4/32', '::192.0.2.4/128'])

^^^^^^^^^^^^^^^^^^^^^^^^
set symmetric difference
^^^^^^^^^^^^^^^^^^^^^^^^

>>> s1 ^ s2
IPSet(['192.0.2.0/32', '192.0.2.4/32', '::192.0.2.0/128', '::192.0.2.4/128'])

------------------
Disjointed IP sets
------------------

>>> s1 = IPSet(['192.0.2.0', '192.0.2.1', '192.0.2.2'])
>>> s2 = IPSet(['192.0.2.2', '192.0.2.3', '192.0.2.4'])
>>> s1 & s2
IPSet(['192.0.2.2/32'])
>>> s1.isdisjoint(s2)
False
>>> s1 = IPSet(['192.0.2.0', '192.0.2.1'])
>>> s2 = IPSet(['192.0.2.3', '192.0.2.4'])
>>> s1 & s2
IPSet([])
>>> s1.isdisjoint(s2)
True

------------------
Updating an IP set
------------------

As with a normal Python set you can also update one IP set with the contents of another.

>>> s1 = IPSet(['192.0.2.0/25'])
>>> s1
IPSet(['192.0.2.0/25'])
>>> s2 = IPSet(['192.0.2.128/25'])
>>> s2
IPSet(['192.0.2.128/25'])
>>> s1.update(s2)
>>> s1
IPSet(['192.0.2.0/24'])
>>> s1.update(['192.0.0.0/24', '192.0.1.0/24', '192.0.3.0/24'])
>>> s1
IPSet(['192.0.0.0/22'])


--------------------------------
Removing elements from an IP set
--------------------------------

Removing an IP address from an IPSet will the CIDR subnets within it into their constituent parts.

Here we create a set representing the entire IPv4 address space.

>>> s1 = IPSet(['0.0.0.0/0'])
>>> s1
IPSet(['0.0.0.0/0'])

Then we strip off the last address.

>>> s1.remove('255.255.255.255')

Leaving us with:

>>> s1
IPSet(['0.0.0.0/1', '128.0.0.0/2', ..., '255.255.255.252/31', '255.255.255.254/32'])
>>> list(s1.iter_cidrs())
[IPNetwork('0.0.0.0/1'), IPNetwork('128.0.0.0/2'), ..., IPNetwork('255.255.255.252/31'), IPNetwork('255.255.255.254/32')]
>>> len(list(s1.iter_cidrs()))
32

Let's check the result using the `cidr_exclude` function.

>>> list(s1.iter_cidrs()) == cidr_exclude('0.0.0.0/0', '255.255.255.255')
True

Next, let's remove the first address from the original range.

>>> s1.remove('0.0.0.0')

This fractures the CIDR subnets further.

>>> s1
IPSet(['0.0.0.1/32', '0.0.0.2/31', ..., '255.255.255.252/31', '255.255.255.254/32'])
>>> len(list(s1.iter_cidrs()))
62

You can keep doing this but be aware that large IP sets can take up a lot of memory if they contain many thousands of entries.

----------------------------
Adding elements to an IP set
----------------------------

Let's fix up the fractured IP set from the previous section by re-adding the IP addresses we removed.

>>> s1.add('255.255.255.255')
>>> s1
IPSet(['0.0.0.1/32', '0.0.0.2/31', ..., '64.0.0.0/2', '128.0.0.0/1'])

Getting better.

>>> list(s1.iter_cidrs())
[IPNetwork('0.0.0.1/32'), IPNetwork('0.0.0.2/31'), ..., IPNetwork('64.0.0.0/2'), IPNetwork('128.0.0.0/1')]

>>> len(list(s1.iter_cidrs()))
32

Add back the other IP address.

>>> s1.add('0.0.0.0')

And we're back to our original address.

>>> s1
IPSet(['0.0.0.0/0'])

----------------------
Pickling IPSet objects
----------------------

As with all other netaddr classes, you can use ``pickle`` to persist IP sets for later use.

>>> import pickle
>>> ip_data = IPSet(['10.0.0.0/16', 'fe80::/64'])
>>> buf = pickle.dumps(ip_data)
>>> ip_data_unpickled = pickle.loads(buf)
>>> ip_data == ip_data_unpickled
True