Cleanup: validate option at config read level

It's not necessary to make validation for negative retries
in code if we have IntOpt min option.

Change-Id: I3d42472604d86ba2e5e9b674e8ec2017849aa15a

nova/compute/manager.py

@@ -1370,11 +1370,6 @@ class ComputeManager(manager.Manager):
         LOG.debug("Allocating IP information in the background.",
                   instance=instance)
         retries = CONF.network_allocate_retries
-        if retries < 0:
-            LOG.warning(_LW("Treating negative config value (%(retries)s) for "
-                            "'network_allocate_retries' as 0."),
-                        {'retries': retries})
-            retries = 0
         attempts = retries + 1
         retry_time = 1
         bind_host_id = self.driver.network_binding_host_id(context, instance)

nova/conf/compute.py

@@ -226,7 +226,8 @@ compute_manager_opts = [
                      'host rebooted'),
     cfg.IntOpt('network_allocate_retries',
                default=0,
-               help="Number of times to retry network allocation on failures"),
+               help="Number of times to retry network allocation on failures",
+               min=0),
     cfg.IntOpt('max_concurrent_builds',
                default=10,
                help='Maximum number of instance builds to run concurrently'),

nova/tests/unit/compute/test_compute_mgr.py

@@ -425,33 +425,6 @@ class ComputeManagerUnitTestCase(test.NoDBTestCase):
             dhcp_options=dhcp_options,
             bind_host_id=instance.get('host'))
 
-    @mock.patch.object(network_api.API, 'allocate_for_instance')
-    def test_allocate_network_neg_conf_value_treated_as_zero(self,
-                                                             mock_allocate):
-        self.flags(network_allocate_retries=-1)
-
-        mock_allocate.side_effect = test.TestingException
-
-        instance = {}
-        is_vpn = 'fake-is-vpn'
-        req_networks = objects.NetworkRequestList(
-            objects=[objects.NetworkRequest(network_id='fake')])
-        macs = 'fake-macs'
-        sec_groups = 'fake-sec-groups'
-        dhcp_options = None
-
-        self.assertRaises(test.TestingException,
-                          self.compute._allocate_network_async,
-                          self.context, instance, req_networks, macs,
-                          sec_groups, is_vpn, dhcp_options)
-
-        mock_allocate.assert_called_once_with(
-            self.context, instance, vpn=is_vpn,
-            requested_networks=req_networks, macs = macs,
-            security_groups=sec_groups,
-            dhcp_options=dhcp_options,
-            bind_host_id=instance.get('host'))
-
     @mock.patch.object(network_api.API, 'allocate_for_instance')
     @mock.patch.object(manager.ComputeManager, '_instance_update')
     @mock.patch.object(time, 'sleep')

releasenotes/notes/network-allocate-retries-min-a5288476b11bfe55.yaml

@@ -0,0 +1,5 @@
+---
+other:
+  - |
+    network_allocate_retries config param now allows only
+    positive integer values or 0.