adding an option for the filter ipsubnet and testing

docs/docsite/rst/user_guide/playbooks_filters_ipaddr.rst

@@ -474,6 +474,28 @@ smaller subnets::
     # {{ address | ipsubnet(18, -5) }}
     192.168.144.0/27
 
+By specifying an other subnet as a second argument, if the second subnet include
+the first you can have the rank of the first subnet in the second ::
+
+    # The rank of the ip in the subnet (the ip is the 36870nth /32 of the subnet)
+    # {{ address | ipsubnet(subnet) }}
+    36870
+
+    # The rank in the /24 that contain the address
+    # {{ address | ipsubnet('192.168.144.0/24') }}
+    6
+
+    # An IP with the subnet in the first /30 in a /24
+    # {{ '192.168.144.1/30' | ipsubnet('192.168.144.0/24') }}
+    1
+
+    # The fifth subnet /30 in a /24
+    # {{ '192.168.144.16/30' | ipsubnet('192.168.144.0/24') }}
+    5
+
+If the secound subnet doesn't include the first it raise an error
+
+
 You can use ``ipsubnet()`` filter with ``ipaddr()`` filter to for example split
 given ``/48`` prefix into smaller, ``/64`` subnets::
 

lib/ansible/plugins/filter/ipaddr.py

@@ -21,6 +21,7 @@
 
 from functools import partial
 import types
+from ansible.module_utils import six
 
 try:
     import netaddr
@@ -736,6 +737,9 @@ def ipv6(value, query=''):
 #
 #  - address | ipsubnet(cidr, index)
 #      returns next indexed subnet which contains given address
+#
+#  - address/prefix | ipsubnet(subnet/prefix)
+#      return the index of the subnet in the subnet
 def ipsubnet(value, query='', index='x'):
     ''' Manipulate IPv4/IPv6 subnets '''
 
@@ -749,11 +753,11 @@ def ipsubnet(value, query='', index='x'):
         value = netaddr.IPNetwork(v)
     except:
         return False
-
+    query_string = str(query)
     if not query:
         return str(value)
 
-    elif str(query).isdigit():
+    elif query_string.isdigit():
         vsize = ipaddr(v, 'size')
         query = int(query)
 
@@ -786,6 +790,21 @@ def ipsubnet(value, query='', index='x'):
                 except:
                     return False
 
+    elif query_string:
+        vtype = ipaddr(query, 'type')
+        if vtype == 'address':
+            v = ipaddr(query, 'cidr')
+        elif vtype == 'network':
+            v = ipaddr(query, 'subnet')
+        else:
+            msg = 'You must pass a valid subnet or IP address; {0} is invalid'.format(query_string)
+            raise errors.AnsibleFilterError(msg)
+        query = netaddr.IPNetwork(v)
+        for i, subnet in enumerate(query.subnet(value.prefixlen), 1):
+            if subnet == value:
+                return str(i)
+        msg = '{0} is not in the subnet {1}'.format(value.cidr, query.cidr)
+        raise errors.AnsibleFilterError(msg)
     return False
 
 

test/units/plugins/filter/test_ipaddr.py

@@ -21,7 +21,7 @@
 
 from ansible.compat.tests import unittest
 from ansible.errors import AnsibleFilterError
-from ansible.plugins.filter.ipaddr import (ipaddr, _netmask_query, nthhost, next_nth_usable,
+from ansible.plugins.filter.ipaddr import (ipaddr, _netmask_query, nthhost, next_nth_usable, ipsubnet,
                                            previous_nth_usable, network_in_usable, network_in_network,
                                            cidr_merge, ipmath)
 netaddr = pytest.importorskip('netaddr')
@@ -502,3 +502,44 @@ def test_ipmath(self):
         with self.assertRaises(AnsibleFilterError) as exc:
             ipmath('1.2.3.4', 'some_number')
         self.assertEqual(exc.exception.message, expected)
+
+    def test_ipsubnet(self):
+        test_cases = (
+            (('1.1.1.1/24', '30'), '64'),
+            (('1.1.1.1/25', '24'), '0'),
+            (('1.12.1.34/32', '1.12.1.34/24'), '35'),
+            (('192.168.50.0/24', '192.168.0.0/16'), '51'),
+            (('192.168.144.5', '192.168.0.0/16'), '36870'),
+            (('192.168.144.5', '192.168.144.5/24'), '6'),
+            (('192.168.144.5/32', '192.168.144.0/24'), '6'),
+            (('192.168.144.16/30', '192.168.144.0/24'), '5'),
+            (('192.168.144.5', ), '192.168.144.5/32'),
+            (('192.168.0.0/16', ), '192.168.0.0/16'),
+            (('192.168.144.5', ), '192.168.144.5/32'),
+            (('192.168.0.0/16', '20'), '16'),
+            (('192.168.0.0/16', '20', '0'), '192.168.0.0/20'),
+            (('192.168.0.0/16', '20', '-1'), '192.168.240.0/20'),
+            (('192.168.0.0/16', '20', '5'), '192.168.80.0/20'),
+            (('192.168.0.0/16', '20', '-5'), '192.168.176.0/20'),
+            (('192.168.144.5', '20'), '192.168.144.0/20'),
+            (('192.168.144.5', '18', '0'), '192.168.128.0/18'),
+            (('192.168.144.5', '18', '-1'), '192.168.144.4/31'),
+            (('192.168.144.5', '18', '5'), '192.168.144.0/23'),
+            (('192.168.144.5', '18', '-5'), '192.168.144.0/27'),
+            (('span', 'test', 'error'), False),
+            (('test', ), False),
+            (('192.168.144.5', '500000', '-5'), False),
+            (('192.168.144.5', '18', '500000'), False),
+            (('200000', '18', '-5'), '0.3.13.64/27'),
+        )
+        for args, res in test_cases:
+            self._test_ipsubnet(args, res)
+
+    def _test_ipsubnet(self, ipsubnet_args, expected_result):
+        self.assertEqual(ipsubnet(*ipsubnet_args), expected_result)
+
+        with self.assertRaisesRegexp(AnsibleFilterError, 'You must pass a valid subnet or IP address; invalid_subnet is invalid'):
+            ipsubnet('192.168.144.5', 'invalid_subnet')
+
+        with self.assertRaisesRegexp(AnsibleFilterError, '192.168.144.0/30 is not in the subnet 192.168.144.4/30'):
+            ipsubnet('192.168.144.1/30', '192.168.144.5/30')