Merge lp:~ltrager/maas/rack_transitioning into lp:~maas-committers/maas/trunk

[Lee Trager]

Allow a machine to transition to and from a rack controller

This allows you to deploy a machine, install a rack controller on it, then delete the rack controller converting it back to a usable but still deployed machine. I added a trigger so the transitions of any node type to any node type are shown in the UI instantly. During testing I realized that we were always setting the owner to the rack controller worker user. This only sets the user if one isn't defined.

[Gavin Panella (allenap)]

This is good stuff. I really like the scenarios in TestNodeTypeChange. I have one big question though, and I think TestNodeTypeChange is actually broken right now (though it's not far off), so Needs Fixing.

review: Needs Fixing

[Lee Trager (ltrager)]

Thanks for the review. I've made the corrections you've suggested and answered your question about testing below. I put _probably_was_machine as a Controller method as I'll need it for regions in a coming branch.

[Gavin Panella (allenap)]

Cool!

review: Approve

[MAAS Lander (maas-lander)]

The attempt to merge lp:~ltrager/maas/rack_transitioning into lp:maas failed. Below is the output from the failed tests.

Hit:1 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial InRelease
Get:2 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-updates InRelease [94.5 kB]
Get:3 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB]
Hit:4 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-backports InRelease
Get:5 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [111 kB]
Get:6 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [50.3 kB]
Fetched 350 kB in 0s (754 kB/s)
Reading package lists...
sudo DEBIAN_FRONTEND=noninteractive apt-get -y \
    --no-install-recommends install apache2 archdetect-deb authbind bash bind9 bind9utils build-essential bzr bzr-builddeb chromium-browser chromium-chromedriver curl daemontools debhelper dh-apport dh-systemd distro-info dnsutils firefox freeipmi-tools git gjs ipython isc-dhcp-common libjs-angularjs libjs-jquery libjs-jquery-hotkeys libjs-yui3-full libjs-yui3-min libpq-dev make nodejs-legacy npm postgresql pxelinux python3-all python3-apt python3-bson python3-convoy python3-coverage python3-crochet python3-cssselect python3-curtin python3-dev python3-distro-info python3-django python3-django-nose python3-django-piston3 python3-dnspython python3-docutils python3-formencode python3-hivex python3-httplib2 python3-jinja2 python3-jsonschema python3-lxml python3-netaddr python3-netifaces python3-novaclient python3-oauth python3-oauthlib python3-openssl python3-paramiko python3-petname python3-pexpect python3-psycopg2 python3-pyinotify python3-pyparsing python3-pyvmomi python3-requests python3-seamicroclient python3-setuptools python3-simplestreams python3-sphinx python3-tempita python3-twisted python3-txtftp python3-tz python3-yaml python3-zope.interface python-bson python-crochet python-django python-django-piston python-djorm-ext-pgarray python-formencode python-lxml python-netaddr python-netifaces python-pocket-lint python-psycopg2 python-simplejson python-tempita python-twisted python-yaml socat syslinux-common tgt ubuntu-cloudimage-keyring wget xvfb
Reading package lists...
Building dependency tree...
Reading state information...
apache2 is already the newest version (2.4.18-2ubuntu3).
archdetect-deb is already the newest version (1.117ubuntu2).
authbind is already the newest version (2.1.1+nmu1).
bash is already the newest version (4.3-14ubuntu1).
build-essential is already the newest version (12.1ubuntu2).
bzr is already the newest version (2.7.0-2ubuntu1).
curl is already the newest version (7.47.0-1ubuntu2).
debhelper is already the newest version (9.20160115ubuntu3).
distro-info is already the newest version (0.14build1).
freeipmi-tools is already the newest version (1.4.11-1ubuntu1).
git is already the newest version (1:2.7.4-0ubuntu1).
isc-dhcp-common is already the newest version (4.3.3-5ubuntu12).
libjs-angularjs is already the newest version (1.2.28-1ubuntu2).
libjs-jquery is already the newest version (1.11.3+dfsg-4).
libjs-yui3-full is already the newest ...

[MAAS Lander (maas-lander)]

The attempt to merge lp:~ltrager/maas/rack_transitioning into lp:maas failed. Below is the output from the failed tests.

Hit:1 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial InRelease
Hit:2 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-updates InRelease
Hit:3 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-backports InRelease
Get:4 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB]
Fetched 94.5 kB in 0s (204 kB/s)
Reading package lists...
sudo DEBIAN_FRONTEND=noninteractive apt-get -y \
    --no-install-recommends install apache2 archdetect-deb authbind bash bind9 bind9utils build-essential bzr bzr-builddeb chromium-browser chromium-chromedriver curl daemontools debhelper dh-apport dh-systemd distro-info dnsutils firefox freeipmi-tools git gjs ipython isc-dhcp-common libjs-angularjs libjs-jquery libjs-jquery-hotkeys libjs-yui3-full libjs-yui3-min libpq-dev make nodejs-legacy npm postgresql pxelinux python3-all python3-apt python3-bson python3-convoy python3-coverage python3-crochet python3-cssselect python3-curtin python3-dev python3-distro-info python3-django python3-django-nose python3-django-piston3 python3-dnspython python3-docutils python3-formencode python3-hivex python3-httplib2 python3-jinja2 python3-jsonschema python3-lxml python3-netaddr python3-netifaces python3-novaclient python3-oauth python3-oauthlib python3-openssl python3-paramiko python3-petname python3-pexpect python3-psycopg2 python3-pyinotify python3-pyparsing python3-pyvmomi python3-requests python3-seamicroclient python3-setuptools python3-simplestreams python3-sphinx python3-tempita python3-twisted python3-txtftp python3-tz python3-yaml python3-zope.interface python-bson python-crochet python-django python-django-piston python-djorm-ext-pgarray python-formencode python-lxml python-netaddr python-netifaces python-pocket-lint python-psycopg2 python-simplejson python-tempita python-twisted python-yaml socat syslinux-common tgt ubuntu-cloudimage-keyring wget xvfb
Reading package lists...
Building dependency tree...
Reading state information...
apache2 is already the newest version (2.4.18-2ubuntu3).
archdetect-deb is already the newest version (1.117ubuntu2).
authbind is already the newest version (2.1.1+nmu1).
bash is already the newest version (4.3-14ubuntu1).
build-essential is already the newest version (12.1ubuntu2).
bzr is already the newest version (2.7.0-2ubuntu1).
curl is already the newest version (7.47.0-1ubuntu2).
debhelper is already the newest version (9.20160115ubuntu3).
distro-info is already the newest version (0.14build1).
freeipmi-tools is already the newest version (1.4.11-1ubuntu1).
git is already the newest version (1:2.7.4-0ubuntu1).
isc-dhcp-common is already the newest version (4.3.3-5ubuntu12).
libjs-angularjs is already the newest version (1.2.28-1ubuntu2).
libjs-jquery is already the newest version (1.11.3+dfsg-4).
libjs-yui3-full is already the newest version (3.5.1-1ubuntu3).
libjs-yui3-min is already the newest version (3.5.1-1ubuntu3).
make is already the newest version (4.1-6).
postgresql is already the newest version (9.5+173).
pxelinux is already the newest version (3:6...

[MAAS Lander (maas-lander)]

The attempt to merge lp:~ltrager/maas/rack_transitioning into lp:maas failed. Below is the output from the failed tests.

Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB]
Hit:2 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial InRelease
Get:3 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-updates InRelease [94.5 kB]
Hit:4 http://prodstack-zone-2.clouds.archive.ubuntu.com/ubuntu xenial-backports InRelease
Fetched 189 kB in 0s (482 kB/s)
Reading package lists...
sudo DEBIAN_FRONTEND=noninteractive apt-get -y \
    --no-install-recommends install apache2 archdetect-deb authbind bash bind9 bind9utils build-essential bzr bzr-builddeb chromium-browser chromium-chromedriver curl daemontools debhelper dh-apport dh-systemd distro-info dnsutils firefox freeipmi-tools git gjs ipython isc-dhcp-common libjs-angularjs libjs-jquery libjs-jquery-hotkeys libjs-yui3-full libjs-yui3-min libpq-dev make nodejs-legacy npm postgresql pxelinux python3-all python3-apt python3-bson python3-convoy python3-crochet python3-cssselect python3-curtin python3-dev python3-distro-info python3-django python3-django-nose python3-django-piston3 python3-dnspython python3-docutils python3-formencode python3-hivex python3-httplib2 python3-jinja2 python3-jsonschema python3-lxml python3-netaddr python3-netifaces python3-novaclient python3-oauth python3-oauthlib python3-openssl python3-paramiko python3-petname python3-pexpect python3-psycopg2 python3-pyinotify python3-pyparsing python3-pyvmomi python3-requests python3-seamicroclient python3-setuptools python3-simplestreams python3-sphinx python3-tempita python3-twisted python3-txtftp python3-tz python3-yaml python3-zope.interface python-bson python-crochet python-django python-django-piston python-djorm-ext-pgarray python-formencode python-lxml python-netaddr python-netifaces python-pocket-lint python-psycopg2 python-simplejson python-tempita python-twisted python-yaml socat syslinux-common tgt ubuntu-cloudimage-keyring wget xvfb
Reading package lists...
Building dependency tree...
Reading state information...
apache2 is already the newest version (2.4.18-2ubuntu3).
archdetect-deb is already the newest version (1.117ubuntu2).
authbind is already the newest version (2.1.1+nmu1).
bash is already the newest version (4.3-14ubuntu1).
build-essential is already the newest version (12.1ubuntu2).
bzr is already the newest version (2.7.0-2ubuntu1).
curl is already the newest version (7.47.0-1ubuntu2).
debhelper is already the newest version (9.20160115ubuntu3).
distro-info is already the newest version (0.14build1).
freeipmi-tools is already the newest version (1.4.11-1ubuntu1).
git is already the newest version (1:2.7.4-0ubuntu1).
isc-dhcp-common is already the newest version (4.3.3-5ubuntu12).
libjs-angularjs is already the newest version (1.2.28-1ubuntu2).
libjs-jquery is already the newest version (1.11.3+dfsg-4).
libjs-yui3-full is already the newest version (3.5.1-1ubuntu3).
libjs-yui3-min is already the newest version (3.5.1-1ubuntu3).
make is already the newest version (4.1-6).
postgresql is already the newest version (9.5+173).
pxelinux is already the newest version (3:6.03+dfsg...

=== modified file 'src/maasserver/models/node.py'
--- src/maasserver/models/node.py	2016-05-26 06:47:45 +0000
+++ src/maasserver/models/node.py	2016-05-26 16:01:00 +0000
@@ -3097,6 +3097,16 @@
     def __init__(self, *args, **kwargs):
         super(Controller, self).__init__(*args, **kwargs)
 
+    def _was_probably_machine(self):
+        """Best guess if a rack was a machine.
+
+        MAAS doesn't track node transitions so we have to look at
+        breadcrumbs. The first is the status. Only machines can have their
+        status changed to something other than NEW and a rack controller should
+        only be installable when the machine is in a deployed state.  Second a
+        machine must have power information."""
+        return self.status == NODE_STATUS.DEPLOYED and self.bmc is not None
+
 
 class RackController(Controller):
     """A node which is running rackd."""
@@ -3659,6 +3669,9 @@
 
     def delete(self):
         """Delete this rack controller."""
+        # Avoid circular imports
+        from maasserver.models import RegionRackRPCConnection
+
         primary_vlans = VLAN.objects.filter(primary_rack=self)
         if len(primary_vlans) != 0:
             raise ValidationError(
@@ -3667,6 +3680,10 @@
                 (self.hostname,
                     ', '.join([str(vlan) for vlan in primary_vlans])))
 
+        # Disable and delete all services related to this node
+        Service.objects.mark_dead(self, dead_rack=True)
+        Service.objects.filter(node=self).delete()
+
         try:
             client = getClientFor(self.system_id, timeout=1)
             call = client(DisableAndShutoffRackd)
@@ -3676,6 +3693,8 @@
             # is currently disconnected or rackd was killed
             pass
 
+        RegionRackRPCConnection.objects.filter(rack_controller=self).delete()
+
         for vlan in VLAN.objects.filter(secondary_rack=self):
             vlan.secondary_rack = None
             vlan.save()
@@ -3683,6 +3702,9 @@
         if self.node_type == NODE_TYPE.REGION_AND_RACK_CONTROLLER:
             self.node_type = NODE_TYPE.REGION_CONTROLLER
             self.save()
+        elif self._was_probably_machine():
+            self.node_type = NODE_TYPE.MACHINE
+            self.save()
         else:
             super().delete()
 

=== modified file 'src/maasserver/models/tests/test_node.py'
--- src/maasserver/models/tests/test_node.py	2016-05-26 06:47:45 +0000
+++ src/maasserver/models/tests/test_node.py	2016-05-26 16:01:00 +0000
@@ -4597,6 +4597,18 @@
             routable_racks, none_routable_racks)
 
 
+class TestController(MAASServerTestCase):
+
+    def test__was_probably_machine_true(self):
+        rack = factory.make_RackController(status=NODE_STATUS.DEPLOYED)
+        rack.bmc = factory.make_BMC()
+        rack.save()
+        self.assertTrue(rack._was_probably_machine())
+
+    def test__was_probably_machine_false(self):
+        self.assertFalse(factory.make_RackController()._was_probably_machine())
+
+
 class TestRackControllerUpdateInterfaces(MAASServerTestCase):
 
     def create_empty_rack_controller(self):
@@ -7022,6 +7034,18 @@
             RackController.DoesNotExist,
             RackController.objects.get, system_id=rackcontroller.system_id)
 
+    def test_deletes_services(self):
+        rack = factory.make_RackController()
+        factory.make_Service(rack)
+        rack.delete()
+        self.assertItemsEqual([], Service.objects.all())
+
+    def test_deletes_region_rack_rpc_connections(self):
+        rack = factory.make_RackController()
+        factory.make_RegionRackRPCConnection(rack_controller=rack)
+        rack.delete()
+        self.assertItemsEqual([], RegionRackRPCConnection.objects.all())
+
     def test_delete_converts_region_and_rack_to_region(self):
         region_and_rack = factory.make_Node(
             node_type=NODE_TYPE.REGION_AND_RACK_CONTROLLER)
@@ -7031,6 +7055,16 @@
             NODE_TYPE.REGION_CONTROLLER,
             Node.objects.get(system_id=system_id).node_type)
 
+    def test_delete_converts_rack_to_machine(self):
+        rack = factory.make_RackController(status=NODE_STATUS.DEPLOYED)
+        rack.power_parameters = {
+            'power_address': 'qemu+ssh://user@host/system',
+        }
+        rack.delete()
+        self.assertEquals(
+            NODE_TYPE.MACHINE,
+            Node.objects.get(system_id=rack.system_id).node_type)
+
     def test_update_rackd_status_calls_mark_dead_when_no_connections(self):
         rack_controller = factory.make_RackController()
         mock_mark_dead = self.patch(Service.objects, "mark_dead")

=== modified file 'src/maasserver/rpc/rackcontrollers.py'
--- src/maasserver/rpc/rackcontrollers.py	2016-05-13 15:14:05 +0000
+++ src/maasserver/rpc/rackcontrollers.py	2016-05-26 16:01:00 +0000
@@ -83,8 +83,7 @@
         if rackcontroller.url != url.geturl():
             rackcontroller.url = url.geturl()
             update_fields.append("url")
-    work_user = worker_user.get_worker_user()
-    if rackcontroller.owner != work_user:
+    if rackcontroller.owner is None:
         rackcontroller.owner = worker_user.get_worker_user()
         update_fields.append("owner")
     rackcontroller.save(update_fields=update_fields)

=== modified file 'src/maasserver/rpc/tests/test_rackcontrollers.py'
--- src/maasserver/rpc/tests/test_rackcontrollers.py	2016-05-13 15:14:05 +0000
+++ src/maasserver/rpc/tests/test_rackcontrollers.py	2016-05-26 16:01:00 +0000
@@ -97,11 +97,17 @@
 
 class TestRegisterRackController(MAASServerTestCase):
 
-    def test_sets_owner_to_worker(self):
+    def test_sets_owner_to_worker_when_none(self):
         node = factory.make_Node()
         rack_registered = register_rackcontroller(system_id=node.system_id)
         self.assertEqual(worker_user.get_worker_user(), rack_registered.owner)
 
+    def test_leaves_owner_when_owned(self):
+        user = factory.make_User()
+        node = factory.make_Machine(owner=user)
+        rack_registered = register_rackcontroller(system_id=node.system_id)
+        self.assertEqual(user, rack_registered.owner)
+
     def test_finds_existing_node_by_system_id(self):
         node = factory.make_Node()
         rack_registered = register_rackcontroller(system_id=node.system_id)

=== modified file 'src/maasserver/triggers/tests/test_websocket_listener.py'
--- src/maasserver/triggers/tests/test_websocket_listener.py	2016-04-28 13:53:02 +0000
+++ src/maasserver/triggers/tests/test_websocket_listener.py	2016-05-26 16:01:00 +0000
@@ -2645,3 +2645,128 @@
             self.assertEqual(('delete', '%s' % snippet.id), dv.value)
         finally:
             yield listener.stopService()
+
+
+class TestNodeTypeChange(
+        MAASTransactionServerTestCase, TransactionalHelpersMixin):
+    """End-to-end test of node type change triggers code."""
+
+    scenarios = (
+        ('machine_to_rack', {
+            'from_type': NODE_TYPE.MACHINE,
+            'from_listener': 'machine',
+            'to_type': NODE_TYPE.RACK_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('machine_to_region', {
+            'from_type': NODE_TYPE.MACHINE,
+            'from_listener': 'machine',
+            'to_type': NODE_TYPE.REGION_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('machine_to_rack_and_region', {
+            'from_type': NODE_TYPE.MACHINE,
+            'from_listener': 'machine',
+            'to_type': NODE_TYPE.REGION_AND_RACK_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('machine_to_device', {
+            'from_type': NODE_TYPE.MACHINE,
+            'from_listener': 'machine',
+            'to_type': NODE_TYPE.DEVICE,
+            'to_listener': 'device',
+            }),
+        ('rack_to_machine', {
+            'from_type': NODE_TYPE.RACK_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.MACHINE,
+            'to_listener': 'machine',
+            }),
+        ('rack_to_device', {
+            'from_type': NODE_TYPE.RACK_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.DEVICE,
+            'to_listener': 'device',
+            }),
+        ('region_to_machine', {
+            'from_type': NODE_TYPE.REGION_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.MACHINE,
+            'to_listener': 'machine',
+            }),
+        ('region_to_device', {
+            'from_type': NODE_TYPE.REGION_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.DEVICE,
+            'to_listener': 'device',
+            }),
+        ('region_and_rack_to_machine', {
+            'from_type': NODE_TYPE.REGION_AND_RACK_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.MACHINE,
+            'to_listener': 'machine',
+            }),
+        ('region_and_rack_to_device', {
+            'from_type': NODE_TYPE.REGION_AND_RACK_CONTROLLER,
+            'from_listener': 'controller',
+            'to_type': NODE_TYPE.DEVICE,
+            'to_listener': 'device',
+            }),
+        ('device_to_rack', {
+            'from_type': NODE_TYPE.DEVICE,
+            'from_listener': 'device',
+            'to_type': NODE_TYPE.RACK_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('device_to_region', {
+            'from_type': NODE_TYPE.DEVICE,
+            'from_listener': 'device',
+            'to_type': NODE_TYPE.REGION_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('device_to_rack_and_region', {
+            'from_type': NODE_TYPE.DEVICE,
+            'from_listener': 'device',
+            'to_type': NODE_TYPE.REGION_AND_RACK_CONTROLLER,
+            'to_listener': 'controller',
+            }),
+        ('device_to_machine', {
+            'from_type': NODE_TYPE.DEVICE,
+            'from_listener': 'device',
+            'to_type': NODE_TYPE.MACHINE,
+            'to_listener': 'machine',
+            }),
+    )
+
+    @wait_for_reactor
+    @inlineCallbacks
+    def test__transition_notifies(self):
+        yield deferToDatabase(register_websocket_triggers)
+        listener1 = self.make_listener_without_delay()
+        listener2 = self.make_listener_without_delay()
+        node = yield deferToDatabase(
+            self.create_node, {'node_type': self.from_type})
+        q_from, q_to = DeferredQueue(), DeferredQueue()
+        listener1.register(self.from_listener, lambda *args: q_from.put(args))
+        listener2.register(self.to_listener, lambda *args: q_to.put(args))
+        yield listener1.startService()
+        yield listener2.startService()
+        try:
+            node.node_type = self.to_type
+            yield deferToDatabase(node.save)
+            self.assertEqual(
+                ('delete', node.system_id),
+                (yield deferWithTimeout(2, q_from.get)))
+            self.assertEqual(
+                {
+                    ('create', node.system_id),
+                    ('update', node.system_id),
+                },
+                {
+                    (yield deferWithTimeout(2, q_to.get)),
+                    (yield deferWithTimeout(2, q_to.get)),
+                }
+            )
+        finally:
+            yield listener1.stopService()
+            yield listener2.stopService()

=== modified file 'src/maasserver/triggers/websocket.py'
--- src/maasserver/triggers/websocket.py	2016-04-01 22:54:51 +0000
+++ src/maasserver/triggers/websocket.py	2016-05-26 16:01:00 +0000
@@ -772,6 +772,66 @@
                NODE_TYPE.REGION_AND_RACK_CONTROLLER))
 
 
+def node_type_change():
+    return dedent("""\
+        CREATE OR REPLACE FUNCTION node_type_change_notify()
+        RETURNS trigger AS $$
+        BEGIN
+          IF (OLD.node_type != NEW.node_type AND NOT (
+              (
+                OLD.node_type = {rack_controller} OR
+                OLD.node_type = {region_controller} OR
+                OLD.node_type = {region_and_rack_controller}
+              ) AND (
+                NEW.node_type = {rack_controller} OR
+                NEW.node_type = {region_controller} OR
+                NEW.node_type = {region_and_rack_controller}
+              ))) THEN
+            CASE OLD.node_type
+              WHEN {machine} THEN
+                PERFORM pg_notify('machine_delete',CAST(
+                  OLD.system_id AS TEXT));
+              WHEN {device} THEN
+                PERFORM pg_notify('device_delete',CAST(
+                  OLD.system_id AS TEXT));
+              WHEN {rack_controller} THEN
+                PERFORM pg_notify('controller_delete',CAST(
+                  OLD.system_id AS TEXT));
+              WHEN {region_controller} THEN
+                PERFORM pg_notify('controller_delete',CAST(
+                  OLD.system_id AS TEXT));
+              WHEN {region_and_rack_controller} THEN
+                PERFORM pg_notify('controller_delete',CAST(
+                  OLD.system_id AS TEXT));
+            END CASE;
+            CASE NEW.node_type
+              WHEN {machine} THEN
+                PERFORM pg_notify('machine_create',CAST(
+                  NEW.system_id AS TEXT));
+              WHEN {device} THEN
+                PERFORM pg_notify('device_create',CAST(
+                  NEW.system_id AS TEXT));
+              WHEN {rack_controller} THEN
+                PERFORM pg_notify('controller_create',CAST(
+                  NEW.system_id AS TEXT));
+              WHEN {region_controller} THEN
+                PERFORM pg_notify('controller_create',CAST(
+                  NEW.system_id AS TEXT));
+              WHEN {region_and_rack_controller} THEN
+                PERFORM pg_notify('controller_create',CAST(
+                  NEW.system_id AS TEXT));
+            END CASE;
+          END IF;
+          RETURN NEW;
+        END;
+        $$ LANGUAGE plpgsql;
+    """.format(
+        machine=NODE_TYPE.MACHINE, device=NODE_TYPE.DEVICE,
+        rack_controller=NODE_TYPE.RACK_CONTROLLER,
+        region_controller=NODE_TYPE.REGION_CONTROLLER,
+        region_and_rack_controller=NODE_TYPE.REGION_AND_RACK_CONTROLLER))
+
+
 @transactional
 def register_websocket_triggers():
     """Register all websocket triggers into the database."""
@@ -1414,3 +1474,7 @@
         "maasserver_dhcpsnippet", "dhcpsnippet_update_notify", "update")
     register_trigger(
         "maasserver_dhcpsnippet", "dhcpsnippet_delete_notify", "delete")
+
+    register_procedure(node_type_change())
+    register_trigger(
+        "maasserver_node", "node_type_change_notify", "update")