[openstack-hypervisor] error out on snap installation failure

When the openstack-hypervisor snap fails to install, then set
the unit status to error instead of blocked.

Closes-Bug: #2065944.

Change-Id: I0b3817c8e8321e5bfd8eaabe63646c9cd48cdf36

charms/openstack-hypervisor/src/charm.py

@@ -71,6 +71,10 @@ DATA_BINDING = "data"
 MTLS_USAGES = {x509.OID_SERVER_AUTH, x509.OID_CLIENT_AUTH}
 
 
+class SnapInstallationError(Exception):
+    """Custom exception for snap installation failure errors."""
+
+
 class HypervisorError(Exception):
     """Custom exception for Hypervisor errors."""
 
@@ -217,7 +221,10 @@ class HypervisorOperatorCharm(sunbeam_charm.OSBaseOperatorCharm):
 
     def _on_install(self, _: ops.InstallEvent):
         """Run install on this unit."""
-        self.ensure_snap_present()
+        with sunbeam_guard.guard(
+            self, "Executing install hook event handler", False
+        ):
+            self.ensure_snap_present()
 
     @property
     def migration_address(self) -> Optional[str]:
@@ -490,12 +497,16 @@ class HypervisorOperatorCharm(sunbeam_charm.OSBaseOperatorCharm):
                 hypervisor.ensure(
                     snap.SnapState.Latest, channel=config("snap-channel")
                 )
-        except snap.SnapError as e:
+        except (snap.SnapError, snap.SnapNotFoundError) as e:
             logger.error(
                 "An exception occurred when installing openstack-hypervisor. Reason: %s",
                 e.message,
             )
 
+            raise SnapInstallationError(
+                "openstack-hypervisor installation failed"
+            )
+
     @functools.cache
     def get_snap_cache(self) -> snap.SnapCache:
         """Return snap cache."""

charms/openstack-hypervisor/tests/unit/test_charm.py

@@ -21,6 +21,7 @@ from unittest.mock import (
 )
 
 import charm
+import charms.operator_libs_linux.v2.snap as snap
 import ops
 import ops.testing
 import ops_sunbeam.test_utils as test_utils
@@ -289,6 +290,13 @@ class TestCharm(test_utils.CharmTestCase):
         }
         hypervisor_snap_mock.set.assert_any_call(expect_settings, typed=True)
 
+    def test_openstack_hypervisor_snap_not_installed(self):
+        """Check action raises SnapNotFoundError if openstack-hypervisor snap is not installed."""
+        self.harness.begin()
+        self.snap.SnapCache.side_effect = snap.SnapNotFoundError
+        with self.assertRaises(snap.SnapNotFoundError):
+            self.harness.run_action("list-nics")
+
     def test_list_nics_snap_not_installed(self):
         """Check action raises ActionFailed if snap is not installed."""
         self.harness.begin()

charms/sunbeam-clusterd/src/charm.py

@@ -63,6 +63,10 @@ def _identity(x: bool) -> bool:
     return x
 
 
+class SnapInstallationError(Exception):
+    """Custom exception for snap installation failure errors."""
+
+
 @sunbeam_tracing.trace_type
 class ClusterCertificatesHandler(sunbeam_rhandlers.TlsCertificatesHandler):
     """Handler for certificates interface."""
@@ -204,7 +208,8 @@ class SunbeamClusterdCharm(sunbeam_charm.OSBaseOperatorCharm):
     def _on_install(self, event: ops.InstallEvent) -> None:
         """Handle install event."""
         try:
-            self.ensure_snap_present()
+            with sunbeam_guard.guard(self, "Ensure snap installation", False):
+                self.ensure_snap_present()
         except TimeoutError:
             logger.debug("Snap installation failed, retrying.")
             event.defer()
@@ -275,11 +280,12 @@ class SunbeamClusterdCharm(sunbeam_charm.OSBaseOperatorCharm):
                 openstack.ensure(snap.SnapState.Latest, channel=snap_channel)
                 self._state.channel = openstack.channel
                 self.set_workload_version()
-        except snap.SnapError as e:
+        except (snap.SnapError, snap.SnapNotFoundError) as e:
             logger.error(
                 "An exception occurred when installing snap. Reason: %s",
                 e.message,
             )
+            raise SnapInstallationError("openstack snap installation failed")
 
     def set_workload_version(self):
         """Set workload version."""

charms/sunbeam-clusterd/tests/unit/test_charm.py

@@ -15,6 +15,9 @@ import ops
 import ops.testing as testing
 import ops_sunbeam.test_utils as test_utils
 import yaml
+from charms.operator_libs_linux.v2 import (
+    snap,
+)
 
 
 class _SunbeamClusterdCharm(charm.SunbeamClusterdCharm):
@@ -59,6 +62,13 @@ class TestCharm(test_utils.CharmTestCase):
         self.harness.add_network("10.0.0.10")
         self.harness.begin_with_initial_hooks()
 
+    def test_openstack_snap_not_installed(self):
+        """Check action raises SnapNotFoundError if openstack snap is not installed."""
+        self.harness.begin()
+        self.ensure_snap_present.side_effect = snap.SnapNotFoundError
+        with self.assertRaises(snap.SnapNotFoundError):
+            self.harness.charm.on.install.emit()
+
     def test_initial_bootstrap(self):
         """Test charm is bootstrapped."""
         self.initial_setup()