[AKS] az aks create/update: Support in place param updates for managed prom (#29273)

Author: bragi92

src/azure-cli/azure/cli/command_modules/acs/azuremonitormetrics/azuremonitorprofile.py

@@ -89,17 +89,22 @@ def ensure_azure_monitor_profile_prerequisites(
             cluster_name
         )
     else:
+        is_prometheus_enabled = False
         # Check if already onboarded
         if create_flow is False:
-            check_azuremonitormetrics_profile(cmd, cluster_subscription, cluster_resource_group_name, cluster_name)
-        # Do RP registrations if required
-        rp_registrations(cmd, cluster_subscription, raw_parameters)
-        link_azure_monitor_profile_artifacts(
-            cmd,
-            cluster_subscription,
-            cluster_resource_group_name,
-            cluster_name,
-            cluster_region,
-            raw_parameters,
-            create_flow
-        )
+            is_prometheus_enabled = check_azuremonitormetrics_profile(cmd, cluster_subscription, cluster_resource_group_name, cluster_name)
+        if is_prometheus_enabled:
+            print("Azure Prometheus is already enabled : This command will only allow updates to the KSM parameters. All other parameters will be ignored")
+        # Do RP registrations and artifact creation (DC*, rules, grafana link etc.) if not enabled already
+        # Otherwise move forward so that the addon can be enabled with new KSM parameters
+        if is_prometheus_enabled is False:
+            rp_registrations(cmd, cluster_subscription, raw_parameters)
+            link_azure_monitor_profile_artifacts(
+                cmd,
+                cluster_subscription,
+                cluster_resource_group_name,
+                cluster_name,
+                cluster_region,
+                raw_parameters,
+                create_flow
+            )

src/azure-cli/azure/cli/command_modules/acs/azuremonitormetrics/helper.py

@@ -112,4 +112,5 @@ def check_azuremonitormetrics_profile(cmd, cluster_subscription, cluster_resourc
     if "azureMonitorProfile" in values_array:
         if "metrics" in values_array["azureMonitorProfile"]:
             if values_array["azureMonitorProfile"]["metrics"]["enabled"] is True:
-                raise CLIError(f"Azure Monitor Metrics is already enabled for this cluster. Please use `az aks update --disable-azure-monitor-metrics -g {cluster_resource_group_name} -n {cluster_name}` and then try enabling.")
+                return True
+    return False