Refactoring of L3 agent notifications for router

The goal of this refactoring is to reduce duplication by
replacing the L3EventObservers mechanism (a specific
mechanism for L3 agent notifications), with the
CallbacksManager mechanism (a more general mechanism
currently in use), so that there is one method
used.

This is the first part of refactoring the L3 agent so that
it uses the new neutron.callbacks mechanism. To do this,
duplicate calls will be made for notifications related to
the router, only using the new callback mechanism.

This commit does two things. First, it puts in place the
notifiers for the new callback mechanism. Second, it updates
the metatdata proxy agent (which is in the same repo) to
use the new callback mechanism.

Later commits will update other repos from the old to new
callback mechanism, and to then remove the old callback
mechanism, once no longer used.

Change-Id: If134947957fd671aa99a0b2d2b37f7ec65e37766
Partial-Bug: #1433552

diff --git a/neutron/agent/l3/agent.py b/neutron/agent/l3/agent.py
index 3c754d46e957220222bae81543f73fd90db2adc6..9e9b8a9915610935526dfe0a5e08f40d40bb71f8 100644 (file)
--- a/neutron/agent/l3/agent.py
+++ b/neutron/agent/l3/agent.py
@@ -35,6 +35,9 @@ from neutron.agent.linux import external_process
 from neutron.agent.linux import ip_lib
 from neutron.agent.metadata import driver as metadata_driver
 from neutron.agent import rpc as agent_rpc
+from neutron.callbacks import events
+from neutron.callbacks import registry
+from neutron.callbacks import resources
 from neutron.common import constants as l3_constants
 from neutron.common import exceptions as n_exc
 from neutron.common import ipv6_utils
@@ -220,7 +223,6 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback,
 
         if self.conf.enable_metadata_proxy:
             self.metadata_driver = metadata_driver.MetadataDriver(self)
-            self.event_observers.add(self.metadata_driver)
 
     def _check_config_params(self):
         """Check items in configuration files.
@@ -309,6 +311,8 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback,
         ri = self._create_router(router_id, router)
         self.event_observers.notify(
             adv_svc.AdvancedService.before_router_added, ri)
+        registry.notify(resources.ROUTER, events.BEFORE_CREATE,
+                        self, router=ri)
 
         self.router_info[router_id] = ri
 
@@ -326,12 +330,15 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback,
 
         self.event_observers.notify(
             adv_svc.AdvancedService.before_router_removed, ri)
+        registry.notify(resources.ROUTER, events.BEFORE_DELETE,
+                        self, router=ri)
 
         ri.delete(self)
         del self.router_info[router_id]
 
         self.event_observers.notify(
             adv_svc.AdvancedService.after_router_removed, ri)
+        registry.notify(resources.ROUTER, events.AFTER_DELETE, self, router=ri)
 
     def update_fip_statuses(self, ri, existing_floating_ips, fip_statuses):
         # Identify floating IPs which were disabled
@@ -413,15 +420,19 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback,
         ri.process(self)
         self.event_observers.notify(
             adv_svc.AdvancedService.after_router_added, ri)
+        registry.notify(resources.ROUTER, events.AFTER_CREATE, self, router=ri)
 
     def _process_updated_router(self, router):
         ri = self.router_info[router['id']]
         ri.router = router
         self.event_observers.notify(
             adv_svc.AdvancedService.before_router_updated, ri)
+        registry.notify(resources.ROUTER, events.BEFORE_UPDATE,
+                        self, router=ri)
         ri.process(self)
         self.event_observers.notify(
             adv_svc.AdvancedService.after_router_updated, ri)
+        registry.notify(resources.ROUTER, events.AFTER_UPDATE, self, router=ri)
 
     def _process_router_update(self):
         for rp, update in self._queue.each_update_to_next_router():

diff --git a/neutron/agent/metadata/driver.py b/neutron/agent/metadata/driver.py
index 9378a3a930c950bcb4ff148facc84a4a6925fa61..c5088fd2c2ef718e3e189c5c3de856c95ee44aa9 100644 (file)
--- a/neutron/agent/metadata/driver.py
+++ b/neutron/agent/metadata/driver.py
@@ -22,6 +22,9 @@ from neutron.agent.common import config
 from neutron.agent.l3 import namespaces
 from neutron.agent.linux import external_process
 from neutron.agent.linux import utils
+from neutron.callbacks import events
+from neutron.callbacks import registry
+from neutron.callbacks import resources
 from neutron.common import exceptions
 from neutron.services import advanced_service
 
@@ -66,39 +69,10 @@ class MetadataDriver(advanced_service.AdvancedService):
         super(MetadataDriver, self).__init__(l3_agent)
         self.metadata_port = l3_agent.conf.metadata_port
         self.metadata_access_mark = l3_agent.conf.metadata_access_mark
-
-    def after_router_added(self, router):
-        for c, r in self.metadata_filter_rules(self.metadata_port,
-                                               self.metadata_access_mark):
-            router.iptables_manager.ipv4['filter'].add_rule(c, r)
-        for c, r in self.metadata_mangle_rules(self.metadata_access_mark):
-            router.iptables_manager.ipv4['mangle'].add_rule(c, r)
-        for c, r in self.metadata_nat_rules(self.metadata_port):
-            router.iptables_manager.ipv4['nat'].add_rule(c, r)
-        router.iptables_manager.apply()
-
-        if not router.is_ha:
-            self.spawn_monitored_metadata_proxy(
-                self.l3_agent.process_monitor,
-                router.ns_name,
-                self.metadata_port,
-                self.l3_agent.conf,
-                router_id=router.router_id)
-
-    def before_router_removed(self, router):
-        for c, r in self.metadata_filter_rules(self.metadata_port,
-                                               self.metadata_access_mark):
-            router.iptables_manager.ipv4['filter'].remove_rule(c, r)
-        for c, r in self.metadata_mangle_rules(self.metadata_access_mark):
-            router.iptables_manager.ipv4['mangle'].remove_rule(c, r)
-        for c, r in self.metadata_nat_rules(self.metadata_port):
-            router.iptables_manager.ipv4['nat'].remove_rule(c, r)
-        router.iptables_manager.apply()
-
-        self.destroy_monitored_metadata_proxy(self.l3_agent.process_monitor,
-                                              router.router['id'],
-                                              router.ns_name,
-                                              self.l3_agent.conf)
+        registry.subscribe(
+            after_router_added, resources.ROUTER, events.AFTER_CREATE)
+        registry.subscribe(
+            before_router_removed, resources.ROUTER, events.BEFORE_DELETE)
 
     @classmethod
     def metadata_filter_rules(cls, port, mark):
@@ -192,3 +166,42 @@ class MetadataDriver(advanced_service.AdvancedService):
             uuid=router_id,
             namespace=ns_name,
             default_cmd_callback=callback)
+
+
+def after_router_added(resource, event, l3_agent, **kwargs):
+    router = kwargs['router']
+    proxy = l3_agent.metadata_driver
+    for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
+                                           proxy.metadata_access_mark):
+        router.iptables_manager.ipv4['filter'].add_rule(c, r)
+    for c, r in proxy.metadata_mangle_rules(proxy.metadata_access_mark):
+        router.iptables_manager.ipv4['mangle'].add_rule(c, r)
+    for c, r in proxy.metadata_nat_rules(proxy.metadata_port):
+        router.iptables_manager.ipv4['nat'].add_rule(c, r)
+    router.iptables_manager.apply()
+
+    if not router.is_ha:
+        proxy.spawn_monitored_metadata_proxy(
+            l3_agent.process_monitor,
+            router.ns_name,
+            proxy.metadata_port,
+            l3_agent.conf,
+            router_id=router.router_id)
+
+
+def before_router_removed(resource, event, l3_agent, **kwargs):
+    router = kwargs['router']
+    proxy = l3_agent.metadata_driver
+    for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
+                                           proxy.metadata_access_mark):
+        router.iptables_manager.ipv4['filter'].remove_rule(c, r)
+    for c, r in proxy.metadata_mangle_rules(proxy.metadata_access_mark):
+        router.iptables_manager.ipv4['mangle'].remove_rule(c, r)
+    for c, r in proxy.metadata_nat_rules(proxy.metadata_port):
+        router.iptables_manager.ipv4['nat'].remove_rule(c, r)
+    router.iptables_manager.apply()
+
+    proxy.destroy_monitored_metadata_proxy(l3_agent.process_monitor,
+                                          router.router['id'],
+                                          router.ns_name,
+                                          l3_agent.conf)

diff --git a/neutron/tests/functional/agent/test_l3_agent.py b/neutron/tests/functional/agent/test_l3_agent.py
old mode 100644 (file)
new mode 100755 (executable)
index 930ca5a..719ab60
--- a/neutron/tests/functional/agent/test_l3_agent.py
+++ b/neutron/tests/functional/agent/test_l3_agent.py
@@ -36,6 +36,8 @@ from neutron.agent.linux import dhcp
 from neutron.agent.linux import external_process
 from neutron.agent.linux import ip_lib
 from neutron.agent.linux import utils
+from neutron.callbacks import manager
+from neutron.callbacks import registry
 from neutron.common import config as common_config
 from neutron.common import constants as l3_constants
 from neutron.common import utils as common_utils
@@ -60,6 +62,12 @@ class L3AgentTestFramework(base.BaseOVSLinuxTestCase):
     def setUp(self):
         super(L3AgentTestFramework, self).setUp()
         mock.patch('neutron.agent.l3.agent.L3PluginApi').start()
+
+        # TODO(pcm): Move this to BaseTestCase, if we find that more tests
+        # use this mechanism.
+        self._callback_manager = manager.CallbacksManager()
+        mock.patch.object(registry, '_get_callback_manager',
+                          return_value=self._callback_manager).start()
         self.agent = self._configure_agent('agent1')
 
     def _get_config_opts(self):

diff --git a/neutron/tests/unit/test_l3_agent.py b/neutron/tests/unit/test_l3_agent.py
index a6021318a7b24fbc457be3361fb37266b5ce694c..67b5d174cdde4fd34c369a3259823c2453c3bf39 100644 (file)
--- a/neutron/tests/unit/test_l3_agent.py
+++ b/neutron/tests/unit/test_l3_agent.py
@@ -37,6 +37,8 @@ from neutron.agent.linux import external_process
 from neutron.agent.linux import interface
 from neutron.agent.linux import ra
 from neutron.agent.metadata import driver as metadata_driver
+from neutron.callbacks import manager
+from neutron.callbacks import registry
 from neutron.common import config as base_config
 from neutron.common import constants as l3_constants
 from neutron.common import exceptions as n_exc
@@ -45,7 +47,6 @@ from neutron.openstack.common import uuidutils
 from neutron.plugins.common import constants as p_const
 from neutron.tests import base
 
-
 _uuid = uuidutils.generate_uuid
 HOSTNAME = 'myhost'
 FAKE_ID = _uuid()
@@ -310,6 +311,10 @@ class BasicRouterOperationsFramework(base.BaseTestCase):
         self.ri_kwargs = {'agent_conf': self.conf,
                           'interface_driver': self.mock_driver}
 
+        self._callback_manager = manager.CallbacksManager()
+        mock.patch.object(registry, '_get_callback_manager',
+                          return_value=self._callback_manager).start()
+
     def _process_router_instance_for_agent(self, agent, ri, router):
         ri.router = router
         if not ri.radvd: