x/vmware-nsx
Code Issues Proposed changes

Handle exceptions on create_dhcp_port

Browse Source 
If a network/subnet is deleted while creating the dhcp
port, the agent will detect a conflict on state of the
network and deal with it accordingly.

A concurrent delete may manifest itself via a number
of exceptions, IPAddressGenerationFailure amongst others,
hence the refactoring of the error handling logic into its
own utility method.

Partial-bug: #1253344
Related-bug: #1243726

Change-Id: I442beb5f82f3db8786eea53926903ef0ba0efbf1
This commit is contained in:
armando-migliaccio 2013-11-21 18:42:08 -08:00
parent 76280f5180
commit 08e3abd414
5 changed files with 125 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
neutron/agent/dhcp_agent.py
View File

@ -127,7 +127,13 @@ class DhcpAgent(manager.Manager):
getattr(driver, action)(**action_kwargs)
return True
except exceptions.Conflict:
# No need to resync here, the agent will receive the event related
# to a status update for the network
LOG.warning(_('Unable to %(action)s dhcp for %(net_id)s: there is '
'a conflict with its current state; please check '
'that the network and/or its subnet(s) still exist.')
% {'net_id': network.id, 'action': action})
except Exception as e:
self.needs_resync = True
if (isinstance(e, common.RemoteError)
@ -432,11 +438,13 @@ class DhcpPluginApi(proxy.RpcProxy):
def create_dhcp_port(self, port):
"""Make a remote process call to create the dhcp port."""
return dhcp.DictModel(self.call(self.context,
self.make_msg('create_dhcp_port',
port=port,
host=self.host),
topic=self.topic))
port = self.call(self.context,
self.make_msg('create_dhcp_port',
port=port,
host=self.host),
topic=self.topic)
if port:
return dhcp.DictModel(port)
def update_dhcp_port(self, port_id, port):
"""Make a remote process call to update the dhcp port."""

3
neutron/agent/linux/dhcp.py
View File

@ -691,6 +691,9 @@ class DeviceManager(object):
fixed_ips=[dict(subnet_id=s) for s in dhcp_enabled_subnet_ids])
dhcp_port = self.plugin.create_dhcp_port({'port': port_dict})
if not dhcp_port:
raise exceptions.Conflict()
# Convert subnet_id to subnet dict
fixed_ips = [dict(subnet_id=fixed_ip.subnet_id,
ip_address=fixed_ip.ip_address,

46
neutron/db/dhcp_rpc_base.py
View File

@ -46,6 +46,31 @@ class DhcpRpcCallbackMixin(object):
nets = plugin.get_networks(context, filters=filters)
return nets
def _port_action(self, plugin, context, port, action):
"""Perform port operations taking care of concurrency issues."""
try:
if action == 'create_port':
return plugin.create_port(context, port)
else:
msg = _('Unrecognized action')
raise n_exc.Invalid(message=msg)
except (db_exc.DBError, n_exc.NetworkNotFound,
n_exc.SubnetNotFound, n_exc.IpAddressGenerationFailure) as e:
if isinstance(e, n_exc.IpAddressGenerationFailure):
# Check if the subnet still exists and if it does not, this is
# the reason why the ip address generation failed. In any other
# unlikely event re-raise
try:
subnet_id = port['port']['fixed_ips'][0]['subnet_id']
plugin.get_subnet(context, subnet_id)
except n_exc.SubnetNotFound:
pass
else:
raise
network_id = port['port']['network_id']
LOG.warn(_("Port for network %(net_id)s could not be created: "
"%(reason)s") % {"net_id": network_id, 'reason': e})
def get_active_networks(self, context, **kwargs):
"""Retrieve and return a list of the active network ids."""
# NOTE(arosen): This method is no longer used by the DHCP agent but is
@ -99,7 +124,7 @@ class DhcpRpcCallbackMixin(object):
This method will re-use an existing port if one already exists. When a
port is re-used, the fixed_ip allocation will be updated to the current
network state.
network state. If an expected failure occurs, a None port is returned.
"""
host = kwargs.get('host')
@ -164,14 +189,9 @@ class DhcpRpcCallbackMixin(object):
device_owner='network:dhcp',
fixed_ips=[dict(subnet_id=s) for s in dhcp_enabled_subnet_ids])
try:
retval = plugin.create_port(context, dict(port=port_dict))
except (db_exc.DBError,
n_exc.NetworkNotFound,
n_exc.SubnetNotFound,
n_exc.IpAddressGenerationFailure) as e:
LOG.warn(_("Port for network %(net_id)s could not be created: "
"%(reason)s") % {"net_id": network_id, 'reason': e})
retval = self._port_action(plugin, context, {'port': port_dict},
'create_port')
if not retval:
return
# Convert subnet_id to subnet dict
@ -229,7 +249,11 @@ class DhcpRpcCallbackMixin(object):
'from host %s.'), host)
def create_dhcp_port(self, context, **kwargs):
"""Create the dhcp port."""
"""Create and return dhcp port information.
If an expected failure occurs, a None port is returned.
"""
host = kwargs.get('host')
port = kwargs.get('port')
LOG.debug(_('Create dhcp port %(port)s '
@ -242,7 +266,7 @@ class DhcpRpcCallbackMixin(object):
if 'mac_address' not in port['port']:
port['port']['mac_address'] = attributes.ATTR_NOT_SPECIFIED
plugin = manager.NeutronManager.get_plugin()
return plugin.create_port(context, port)
return self._port_action(plugin, context, port, 'create_port')
def update_dhcp_port(self, context, **kwargs):
"""Update the dhcp port."""

80
neutron/tests/unit/test_db_rpc_base.py
View File

@ -17,6 +17,7 @@ import mock
from neutron.common import exceptions as n_exc
from neutron.db import dhcp_rpc_base
from neutron.openstack.common.db import exception as db_exc
from neutron.tests import base
@ -50,6 +51,53 @@ class TestDhcpRpcCallackMixin(base.BaseTestCase):
self.assertEqual(len(self.log.mock_calls), 1)
def _test__port_action_with_failures(self, exc=None, action=None):
port = {
'network_id': 'foo_network_id',
'device_owner': 'network:dhcp',
'fixed_ips': [{'subnet_id': 'foo_subnet_id'}]
}
self.plugin.create_port.side_effect = exc
self.assertIsNone(self.callbacks._port_action(self.plugin,
mock.Mock(),
{'port': port},
action))
def test__port_action_bad_action(self):
self.assertRaises(
n_exc.Invalid,
self._test__port_action_with_failures,
exc=None,
action='foo_action')
def test_create_port_catch_network_not_found(self):
self._test__port_action_with_failures(
exc=n_exc.NetworkNotFound(net_id='foo_network_id'),
action='create_port')
def test_create_port_catch_subnet_not_found(self):
self._test__port_action_with_failures(
exc=n_exc.SubnetNotFound(subnet_id='foo_subnet_id'),
action='create_port')
def test_create_port_catch_db_error(self):
self._test__port_action_with_failures(exc=db_exc.DBError(),
action='create_port')
def test_create_port_catch_ip_generation_failure_reraise(self):
self.assertRaises(
n_exc.IpAddressGenerationFailure,
self._test__port_action_with_failures,
exc=n_exc.IpAddressGenerationFailure(net_id='foo_network_id'),
action='create_port')
def test_create_port_catch_and_handle_ip_generation_failure(self):
self.plugin.get_subnet.side_effect = (
n_exc.SubnetNotFound(subnet_id='foo_subnet_id'))
self._test__port_action_with_failures(
exc=n_exc.IpAddressGenerationFailure(net_id='foo_network_id'),
action='create_port')
def test_get_network_info_return_none_on_not_found(self):
self.plugin.get_network.side_effect = n_exc.NetworkNotFound(net_id='a')
retval = self.callbacks.get_network_info(mock.Mock(), network_id='a')
@ -110,38 +158,6 @@ class TestDhcpRpcCallackMixin(base.BaseTestCase):
update_port=port_retval)
self.assertEqual(len(self.log.mock_calls), 1)
def _test_get_dhcp_port_with_failures(self,
raise_get_network=None,
raise_create_port=None):
self.plugin.update_port.return_value = None
if raise_get_network:
self.plugin.get_network.side_effect = raise_get_network
else:
self.plugin.get_network.return_value = {'tenant_id': 'foo_tenant'}
if raise_create_port:
self.plugin.create_port.side_effect = raise_create_port
retval = self.callbacks.get_dhcp_port(mock.Mock(),
network_id='netid',
device_id='devid',
host='host')
self.assertIsNone(retval)
def test_get_dhcp_port_catch_not_found_on_get_network(self):
self._test_get_dhcp_port_with_failures(
raise_get_network=n_exc.NetworkNotFound(net_id='a'))
def test_get_dhcp_port_catch_network_not_found_on_create_port(self):
self._test_get_dhcp_port_with_failures(
raise_create_port=n_exc.NetworkNotFound(net_id='a'))
def test_get_dhcp_port_catch_subnet_not_found_on_create_port(self):
self._test_get_dhcp_port_with_failures(
raise_create_port=n_exc.SubnetNotFound(subnet_id='b'))
def test_get_dhcp_port_catch_ip_generation_failure_on_create_port(self):
self._test_get_dhcp_port_with_failures(
raise_create_port=n_exc.IpAddressGenerationFailure(net_id='a'))
def _test_get_dhcp_port_create_new(self, update_port=None):
self.plugin.get_network.return_value = dict(tenant_id='tenantid')
create_spec = dict(tenant_id='tenantid', device_id='devid',

27
neutron/tests/unit/test_dhcp_agent.py
View File

@ -206,7 +206,8 @@ class TestDhcpAgent(base.BaseTestCase):
mock.ANY,
mock.ANY)
def _test_call_driver_failure(self, exc=None, trace_level='exception'):
def _test_call_driver_failure(self, exc=None,
trace_level='exception', expected_sync=True):
network = mock.Mock()
network.id = '1'
self.driver.return_value.foo.side_effect = exc or Exception
@ -219,7 +220,7 @@ class TestDhcpAgent(base.BaseTestCase):
mock.ANY,
mock.ANY)
self.assertEqual(log.call_count, 1)
self.assertTrue(dhcp.needs_resync)
self.assertEqual(expected_sync, dhcp.needs_resync)
def test_call_driver_failure(self):
self._test_call_driver_failure()
@ -234,6 +235,12 @@ class TestDhcpAgent(base.BaseTestCase):
exc=exceptions.NetworkNotFound(net_id='1'),
trace_level='warning')
def test_call_driver_conflict(self):
self._test_call_driver_failure(
exc=exceptions.Conflict(),
trace_level='warning',
expected_sync=False)
def _test_sync_state_helper(self, known_networks, active_networks):
with mock.patch(DHCP_PLUGIN) as plug:
mock_plugin = mock.Mock()
@ -859,6 +866,10 @@ class TestDhcpPluginApiProxy(base.BaseTestCase):
device_id='devid',
host='foo')
def test_get_dhcp_port_none(self):
self.call.return_value = None
self.assertIsNone(self.proxy.get_dhcp_port('netid', 'devid'))
def test_get_active_networks_info(self):
self.proxy.get_active_networks_info()
self.make_msg.assert_called_once_with('get_active_networks_info',
@ -878,6 +889,18 @@ class TestDhcpPluginApiProxy(base.BaseTestCase):
port=port_body,
host='foo')
def test_create_dhcp_port_none(self):
self.call.return_value = None
port_body = (
{'port':
{'name': '', 'admin_state_up': True,
'network_id': fake_network.id,
'tenant_id': fake_network.tenant_id,
'fixed_ips': [{'subnet_id': fake_fixed_ip1.subnet_id}],
'device_id': mock.ANY}})
self.assertIsNone(self.proxy.create_dhcp_port(port_body))
self.proxy.create_dhcp_port(port_body)
def test_update_dhcp_port(self):
port_body = {'port': {'fixed_ips':
[{'subnet_id': fake_fixed_ip1.subnet_id}]}}