Support passing a subnetpool for create_subnet

previously create_subnet would wrongly report that we need to set a cidr
if subnetpool_id is set.

Change-Id: Icf1d6364d281a0b8b3156ae6b24d7ebca80d632b

openstack/cloud/_network.py

@@ -457,6 +457,17 @@ class NetworkCloudMixin:
         """
         return self.network.get_port(id)
 
+    def get_subnetpool(self, name_or_id):
+        """Get a subnetpool by name or ID.
+
+        :param name_or_id: Name or ID of the subnetpool.
+
+        :returns: A network ``Subnetpool`` object if found, else None.
+        """
+        return self.network.find_subnet_pool(
+            name_or_id=name_or_id, ignore_missing=True
+        )
+
     def create_network(
         self,
         name,
@@ -2308,13 +2319,16 @@ class NetworkCloudMixin:
         ipv6_address_mode=None,
         prefixlen=None,
         use_default_subnetpool=False,
+        subnetpool_name_or_id=None,
         **kwargs,
     ):
         """Create a subnet on a specified network.
 
         :param string network_name_or_id: The unique name or ID of the attached
             network. If a non-unique name is supplied, an exception is raised.
-        :param string cidr: The CIDR.
+        :param string cidr: The CIDR.  Only one of ``cidr``,
+            ``use_default_subnetpool`` and ``subnetpool_name_or_id`` may be
+            specified at the same time.
         :param int ip_version: The IP version, which is 4 or 6.
         :param bool enable_dhcp: Set to ``True`` if DHCP is enabled and
             ``False`` if disabled. Default is ``False``.
@@ -2362,10 +2376,15 @@ class NetworkCloudMixin:
         :param string ipv6_address_mode: IPv6 address mode. Valid values are:
             'dhcpv6-stateful', 'dhcpv6-stateless', or 'slaac'.
         :param string prefixlen: The prefix length to use for subnet allocation
-            from a subnet pool.
+            from a subnetpool.
         :param bool use_default_subnetpool: Use the default subnetpool for
-            ``ip_version`` to obtain a CIDR. It is required to pass ``None`` to
+            ``ip_version`` to obtain a CIDR. Only one of ``cidr``,
-            the ``cidr`` argument when enabling this option.
+            ``use_default_subnetpool`` and ``subnetpool_name_or_id`` may be
+            specified at the same time.
+        :param string subnetpool_name_or_id: The unique name or id of the
+            subnetpool to obtain a CIDR from. Only one of ``cidr``,
+            ``use_default_subnetpool`` and ``subnetpool_name_or_id`` may be
+            specified at the same time.
         :param kwargs: Key value pairs to be passed to the Neutron API.
         :returns: The created network ``Subnet`` object.
         :raises: OpenStackCloudException on operation error.
@@ -2387,17 +2406,31 @@ class NetworkCloudMixin:
                 'arg:disable_gateway_ip is not allowed with arg:gateway_ip'
             )
 
-        if not cidr and not use_default_subnetpool:
+        uses_subnetpool = use_default_subnetpool or subnetpool_name_or_id
+        if not cidr and not uses_subnetpool:
             raise exc.OpenStackCloudException(
                 'arg:cidr is required when a subnetpool is not used'
             )
 
-        if cidr and use_default_subnetpool:
+        if cidr and uses_subnetpool:
             raise exc.OpenStackCloudException(
-                'arg:cidr must be set to None when use_default_subnetpool == '
+                'arg:cidr and subnetpool may not be used at the same time'
-                'True'
             )
 
+        if use_default_subnetpool and subnetpool_name_or_id:
+            raise exc.OpenStackCloudException(
+                'arg:use_default_subnetpool and arg:subnetpool_id may not be '
+                'used at the same time'
+            )
+
+        subnetpool = None
+        if subnetpool_name_or_id:
+            subnetpool = self.get_subnetpool(subnetpool_name_or_id)
+            if not subnetpool:
+                raise exc.OpenStackCloudException(
+                    "Subnetpool %s not found." % subnetpool_name_or_id
+                )
+
         # Be friendly on ip_version and allow strings
         if isinstance(ip_version, str):
             try:
@@ -2443,6 +2476,8 @@ class NetworkCloudMixin:
             subnet['prefixlen'] = prefixlen
         if use_default_subnetpool:
             subnet['use_default_subnetpool'] = True
+        if subnetpool:
+            subnet['subnetpool_id'] = subnetpool["id"]
 
         return self.network.create_subnet(**subnet)
 

openstack/tests/unit/cloud/test_subnet.py

@@ -554,6 +554,93 @@ class TestSubnet(base.TestCase):
         self._compare_subnets(mock_subnet_rep, subnet)
         self.assert_calls()
 
+    def test_create_subnet_from_specific_subnetpool(self):
+        pool = [{'start': '172.16.0.2', 'end': '172.16.0.15'}]
+        id = '143296eb-7f47-4755-835c-488123475604'
+        gateway = '172.16.0.1'
+        dns = ['8.8.8.8']
+        routes = [{"destination": "0.0.0.0/0", "nexthop": "123.456.78.9"}]
+        mock_subnet_rep = copy.copy(self.mock_subnet_rep)
+        mock_subnet_rep['allocation_pools'] = pool
+        mock_subnet_rep['dns_nameservers'] = dns
+        mock_subnet_rep['host_routes'] = routes
+        mock_subnet_rep['gateway_ip'] = gateway
+        mock_subnet_rep['subnetpool_id'] = self.mock_subnetpool_rep['id']
+        mock_subnet_rep['cidr'] = self.subnetpool_cidr
+        mock_subnet_rep['id'] = id
+        self.register_uris(
+            [
+                dict(
+                    method='GET',
+                    uri=self.get_mock_url(
+                        'network',
+                        'public',
+                        append=['v2.0', 'networks', self.network_name],
+                    ),
+                    status_code=404,
+                ),
+                dict(
+                    method='GET',
+                    uri=self.get_mock_url(
+                        'network',
+                        'public',
+                        append=['v2.0', 'networks'],
+                        qs_elements=['name=%s' % self.network_name],
+                    ),
+                    json={'networks': [self.mock_network_rep]},
+                ),
+                dict(
+                    method='GET',
+                    uri=self.get_mock_url(
+                        'network',
+                        'public',
+                        append=[
+                            'v2.0',
+                            'subnetpools',
+                            self.mock_subnetpool_rep['id'],
+                        ],
+                    ),
+                    json={"subnetpool": self.mock_subnetpool_rep},
+                ),
+                dict(
+                    method='POST',
+                    uri=self.get_mock_url(
+                        'network', 'public', append=['v2.0', 'subnets']
+                    ),
+                    json={'subnet': mock_subnet_rep},
+                    validate=dict(
+                        json={
+                            'subnet': {
+                                'enable_dhcp': False,
+                                'ip_version': 4,
+                                'network_id': self.mock_network_rep['id'],
+                                'allocation_pools': pool,
+                                'dns_nameservers': dns,
+                                'subnetpool_id': self.mock_subnetpool_rep[
+                                    'id'
+                                ],
+                                'prefixlen': self.prefix_length,
+                                'host_routes': routes,
+                            }
+                        }
+                    ),
+                ),
+            ]
+        )
+        subnet = self.cloud.create_subnet(
+            self.network_name,
+            allocation_pools=pool,
+            dns_nameservers=dns,
+            subnetpool_name_or_id=self.mock_subnetpool_rep['id'],
+            prefixlen=self.prefix_length,
+            host_routes=routes,
+        )
+        mock_subnet_rep.update(
+            {'prefixlen': self.prefix_length, 'use_default_subnetpool': None}
+        )
+        self._compare_subnets(mock_subnet_rep, subnet)
+        self.assert_calls()
+
     def test_delete_subnet(self):
         self.register_uris(
             [

releasenotes/notes/create-subnet-by-subnetpool-eba1129c67ed4d96.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Added support for specifying the subnetpool to use when creating subnets
+    (``subnetpool_name_or_id``)