Add alert rules to jupyter-controller based on the KF093 spec

charms/jupyter-controller/src/prometheus_alert_rules/KubeflowJupyterControllerServices.rules

@@ -0,0 +1,24 @@
+groups:
+- name: KubeflowJupyterControllerServices
+  rules:
+  - alert: KubeflowServiceDown
+    expr: up{} < 1
+    for: 5m
+    labels:
+      severity: critical
+    annotations:
+      summary: "{{ $labels.juju_charm }} service is Down ({{ $labels.juju_model }}/{{ $labels.juju_unit }})"
+      description: |
+       One or more targets of {{ $labels.juju_charm }} charm are down on unit {{ $labels.juju_model }}/{{ $labels.juju_unit }}.
+       LABELS = {{ $labels }}
+
+  - alert: KubeflowServiceIsNotStable
+    expr: avg_over_time(up{}[10m]) < 0.5
+    for: 0m
+    labels:
+      severity: warning
+    annotations:
+      summary: "{{ $labels.juju_charm }} service is not stable ({{ $labels.juju_model }}/{{ $labels.juju_unit }})"
+      description: |
+        {{ $labels.juju_charm }} unit {{ $labels.juju_model }}/{{ $labels.juju_unit }} has been unreachable at least 50% of the time over the last 10 minutes.
+        LABELS = {{ $labels }}

charms/jupyter-controller/tests/unit/test_operator.py

@@ -115,9 +115,11 @@ def test_prometheus_data_set(self, harness: Harness, mocker):
         with open("src/prometheus_alert_rules/model_errors.rule") as f:
             file_alert = yaml.safe_load(f.read())
             test_alerts.append(file_alert["alert"])
-        with open("src/prometheus_alert_rules/unit_unavailable.rule") as f:
+        with open("src/prometheus_alert_rules/KubeflowJupyterControllerServices.rules") as f:
             file_alert = yaml.safe_load(f.read())
-            test_alerts.append(file_alert["alert"])
+            # there 2 alert rules in host_resources.rules
+            for rule in file_alert["groups"][0]["rules"]:
+                test_alerts.append(rule["alert"])
 
         # alert rules
         alert_rules = json.loads(