add rule patching function

examples/rule-patcher.jsonnet

@@ -0,0 +1,31 @@
+local kp =
+  (import 'kube-prometheus/main.libsonnet') +
+  {
+    values+:: {
+      common+: {
+        namespace: 'monitoring',
+      },
+    },
+  };
+
+local rulePatches = import 'rule-patches.libsonnet';
+
+local sanitizePrometheusRules = (import 'kube-prometheus/lib/rule-sanitizer.libsonnet')(rulePatches).sanitizePrometheusRules;
+
+sanitizePrometheusRules({ 'setup/0namespace-namespace': kp.kubePrometheus.namespace } +
+                        {
+                          ['setup/prometheus-operator-' + name]: kp.prometheusOperator[name]
+                          for name in std.filter((function(name) name != 'serviceMonitor' && name != 'prometheusRule'), std.objectFields(kp.prometheusOperator))
+                        } +
+                        // serviceMonitor and prometheusRule are separated so that they can be created after the CRDs are ready
+                        { 'prometheus-operator-serviceMonitor': kp.prometheusOperator.serviceMonitor } +
+                        { 'prometheus-operator-prometheusRule': kp.prometheusOperator.prometheusRule } +
+                        { 'kube-prometheus-prometheusRule': kp.kubePrometheus.prometheusRule } +
+                        { ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
+                        { ['blackbox-exporter-' + name]: kp.blackboxExporter[name] for name in std.objectFields(kp.blackboxExporter) } +
+                        { ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
+                        { ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
+                        { ['kubernetes-' + name]: kp.kubernetesControlPlane[name] for name in std.objectFields(kp.kubernetesControlPlane) }
+                        { ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
+                        { ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
+                        { ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) })

examples/rule-patches.libsonnet

@@ -0,0 +1,26 @@
+{
+  excludedRuleGroups: [
+    'alertmanager.rules',
+  ],
+  excludedRules: [
+    {
+      name: 'prometheus-operator',
+      rules: [
+        { alert: 'PrometheusOperatorListErrors' },
+      ],
+    },
+  ],
+  patchedRules: [
+    {
+      name: 'prometheus-operator',
+      rules: [
+        {
+          alert: 'PrometheusOperatorWatchErrors',
+          labels: {
+            severity: 'info',
+          },
+        },
+      ],
+    },
+  ],
+}