Rollback to 1.28/stable microk8s in functional testing

We use latest/stable by default which very recently updated to
1.29/stable. Unfortunately it appears there are issues [0] with this
version on Debian Bookworm which also happens to be the platform we test
on. Our jobs have been consistently failing in a manner that appears
related to this issue. Update the job to collect logs so that we can
better confirm this is the case and rollback to 1.28 which should be
working.

Also update the AWS tests to handle a recent moto release which
requires us to use mock_aws rather than individual mock_* classes.

[0] https://github.com/canonical/microk8s/issues/4361

Change-Id: I72310521bdabfc3e34a9f2e87ff80f6d7c27c180
Co-Authored-By: James E. Blair <jim@acmegating.com>
Co-Authored-By: Jeremy Stanley <fungi@yuggoth.org>

.zuul.yaml

@@ -4,6 +4,7 @@
     name: nodepool-functional-k8s
     pre-run: playbooks/nodepool-functional-k8s/pre.yaml
     run: playbooks/nodepool-functional-k8s/run.yaml
+    post-run: playbooks/nodepool-functional-k8s/post.yaml
     required-projects:
       - zuul/nodepool
     nodeset: debian-bookworm

nodepool/tests/unit/test_driver_aws.py

@@ -21,7 +21,7 @@ import urllib.parse
 
 import boto3
 import botocore.exceptions
-from moto import mock_ec2, mock_s3, mock_iam
+from moto import mock_aws
 import testtools
 
 from nodepool import config as nodepool_config
@@ -122,9 +122,7 @@ def ebs_quotas(quotas):
 
 class TestDriverAws(tests.DBTestCase):
     log = logging.getLogger("nodepool.TestDriverAws")
-    mock_ec2 = mock_ec2()
-    mock_s3 = mock_s3()
-    mock_iam = mock_iam()
+    mock_aws = mock_aws()
 
     def setUp(self):
         super().setUp()
@@ -144,9 +142,7 @@ class TestDriverAws(tests.DBTestCase):
             fixtures.EnvironmentVariable('AWS_SECRET_ACCESS_KEY', aws_key))
 
         self.fake_aws = FakeAws()
-        self.mock_ec2.start()
-        self.mock_s3.start()
-        self.mock_iam.start()
+        self.mock_aws.start()
 
         self.ec2 = boto3.resource('ec2', region_name='us-west-2')
         self.ec2_client = boto3.client('ec2', region_name='us-west-2')
@@ -197,8 +193,7 @@ class TestDriverAws(tests.DBTestCase):
                           ebs_quotas=getattr(test, '__aws_ebs_quotas__', None))
 
     def tearDown(self):
-        self.mock_ec2.stop()
-        self.mock_s3.stop()
+        self.mock_aws.stop()
         super().tearDown()
 
     def setup_config(self, *args, **kw):

playbooks/nodepool-functional-k8s/post.yaml

@@ -0,0 +1,4 @@
+- hosts: all
+  roles:
+    - name: Collect k8s logs for debugging purposes
+      role: collect-kubernetes-logs

playbooks/nodepool-functional-k8s/pre.yaml

@@ -6,3 +6,4 @@
     - role: ensure-nox
     - role: ensure-kubernetes
       ensure_kubernetes_type: microk8s
+      ensure_kubernetes_microk8s_channel: '1.28/stable'