test: decouple netplan integrations from libnetplan SRU (#6085)

The netplan.io SRU on Jammy is in an unresolved publication state for
140 days. Avoid hard-coding cloud-init integration tests to expect a
specific series to contain libnetplan and instead check the instance
under test to confirm python3-netplan is installed before validating
cloud-init behavior.

Author: blackboxsw

tests/integration_tests/cmd/test_schema.py

@@ -6,9 +6,9 @@
 
 from cloudinit import lifecycle
 from tests.integration_tests.instances import IntegrationInstance
-from tests.integration_tests.releases import CURRENT_RELEASE, JAMMY
 from tests.integration_tests.util import (
     get_feature_flag_value,
+    has_netplanlib,
     verify_clean_boot,
     verify_clean_log,
 )
@@ -103,7 +103,7 @@ def test_network_config_schema_validation(
                 "annotate": NET_V1_ANNOTATED,
             },
         }
-        if CURRENT_RELEASE >= JAMMY:
+        if has_netplanlib(class_client):
             # Support for netplan API available
             content_responses[NET_CFG_V2] = {
                 "out": "Valid schema /root/net.yaml"

tests/integration_tests/modules/test_combined.py

@@ -26,10 +26,11 @@
     OS_IMAGE_TYPE,
     PLATFORM,
 )
-from tests.integration_tests.releases import CURRENT_RELEASE, IS_UBUNTU, JAMMY
+from tests.integration_tests.releases import CURRENT_RELEASE, IS_UBUNTU
 from tests.integration_tests.util import (
     get_feature_flag_value,
     get_inactive_modules,
+    has_netplanlib,
     lxd_has_nocloud,
     network_wait_logged,
     verify_clean_boot,
@@ -99,13 +100,13 @@ def test_netplan_permissions(self, class_client: IntegrationInstance):
         Test that netplan config file is generated with proper permissions
         """
         log = class_client.read_from_file("/var/log/cloud-init.log")
-        if CURRENT_RELEASE < JAMMY:
+        if has_netplanlib(class_client):
+            assert "Rendered netplan config using netplan python API" in log
+        else:
             assert (
                 "No netplan python module. Fallback to write"
                 " /etc/netplan/50-cloud-init.yaml" in log
             )
-        else:
-            assert "Rendered netplan config using netplan python API" in log
         file_perms = class_client.execute(
             "stat -c %a /etc/netplan/50-cloud-init.yaml"
         )

tests/integration_tests/util.py

@@ -590,6 +590,11 @@ def get_feature_flag_value(client: "IntegrationInstance", key):
     return value
 
 
+def has_netplanlib(client: "IntegrationInstance") -> bool:
+    """Return True if netplan python3 pkg is installed on the instance."""
+    return client.execute("dpkg-query -W python3-netplan").ok
+
+
 def override_kernel_command_line(ds_str: str, instance: "IntegrationInstance"):
     """set the kernel command line and reboot, return after boot done