Add public helper method for cleaning floating ips

Some things, like nodepool or utility scripts, need to be able to safely
clean floating ips, but doing so requires knowledge of whether the cloud
in question is using nova or neutron for floating ips, which shade
otherwise hides from the user. Make a helper method that allows the user
to do it on the clouds where it is safe to do automatically.

Change-Id: I93b0c7d0b0eefdfe0fb1cd4a66cdbba9baabeb09

shade/openstackcloud.py

@@ -3320,6 +3320,34 @@ class OpenStackCloud(object):
                     fip_id=floating_ip_id, msg=str(e)))
         return True
 
+    def delete_unattached_floating_ips(self, wait=False, timeout=60):
+        """Safely delete unattached floating ips.
+
+        If the cloud can safely purge any unattached floating ips without
+        race conditions, do so.
+
+        Safely here means a specific thing. It means that you are not running
+        this while another process that might do a two step create/attach
+        is running. You can safely run this  method while another process
+        is creating servers and attaching floating IPs to them if either that
+        process is using add_auto_ip from shade, or is creating the floating
+        IPs by passing in a server to the create_floating_ip call.
+
+        :param wait: Whether to wait for each IP to be deleted
+        :param timeout: How long to wait for each IP
+
+        :returns: True if Floating IPs have been deleted, False if not
+
+        :raises: ``OpenStackCloudException``, on operation error.
+        """
+        processed = []
+        if self._use_neutron_floating():
+            for ip in self.list_floating_ips():
+                if not ip['attached']:
+                    processed.append(self.delete_floating_ip(
+                        id=ip['id'], wait=wait, timeout=timeout))
+        return all(processed) if processed else False
+
     def _attach_ip_to_server(
             self, server, floating_ip,
             fixed_address=None, wait=False,

shade/tests/unit/test_floating_ip_neutron.py

@@ -531,3 +531,36 @@ class TestFloatingIP(base.TestCase):
             fixed_address='192.0.2.129')
 
         self.assertEqual(server, self.fake_server)
+
+    @patch.object(OpenStackCloud, 'delete_floating_ip')
+    @patch.object(OpenStackCloud, 'list_floating_ips')
+    @patch.object(OpenStackCloud, '_use_neutron_floating')
+    def test_cleanup_floating_ips(
+            self, mock_use_neutron_floating, mock_list_floating_ips,
+            mock_delete_floating_ip):
+        mock_use_neutron_floating.return_value = True
+        floating_ips = [{
+            "id": "this-is-a-floating-ip-id",
+            "fixed_ip_address": None,
+            "internal_network": None,
+            "floating_ip_address": "203.0.113.29",
+            "network": "this-is-a-net-or-pool-id",
+            "attached": False,
+            "status": "ACTIVE"
+        }, {
+            "id": "this-is-an-attached-floating-ip-id",
+            "fixed_ip_address": None,
+            "internal_network": None,
+            "floating_ip_address": "203.0.113.29",
+            "network": "this-is-a-net-or-pool-id",
+            "attached": True,
+            "status": "ACTIVE"
+        }]
+
+        mock_list_floating_ips.return_value = floating_ips
+
+        self.client.delete_unattached_floating_ips()
+
+        mock_delete_floating_ip.assert_called_once_with(
+            id="this-is-a-floating-ip-id",
+            timeout=60, wait=False)

shade/tests/unit/test_floating_ip_nova.py

@@ -248,3 +248,16 @@ class TestFloatingIP(base.TestCase):
             fixed_address='192.0.2.129')
 
         self.assertEqual(server, self.fake_server)
+
+    @patch.object(OpenStackCloud, 'delete_floating_ip')
+    @patch.object(OpenStackCloud, 'list_floating_ips')
+    @patch.object(OpenStackCloud, '_use_neutron_floating')
+    def test_cleanup_floating_ips(
+            self, mock_use_neutron_floating, mock_list_floating_ips,
+            mock_delete_floating_ip):
+        mock_use_neutron_floating.return_value = False
+
+        self.client.delete_unattached_floating_ips()
+
+        mock_delete_floating_ip.assert_not_called()
+        mock_list_floating_ips.assert_not_called()