jsonnet: add networkpolicies for components accessed by prometheus

(cherry picked from commit f8c00b9963)
(cherry picked from commit f09b8e5de2e46db85f090549d37eeb878a81842f)

jsonnet/kube-prometheus/components/blackbox-exporter.libsonnet

@@ -250,6 +250,30 @@ function(params) {
       },
     },
 
+  networkPolicy: {
+    apiVersion: 'networking.k8s.io/v1',
+    kind: 'NetworkPolicy',
+    metadata: bb.service.metadata,
+    spec: {
+      podSelector: {
+        matchLabels: bb._config.selectorLabels,
+      },
+      ingress: [{
+        from: [{
+          podSelector: {
+            matchLabels: {
+              'app.kubernetes.io/name': 'prometheus',
+            },
+          },
+        }],
+        ports: std.map(function(o) {
+          port: o.port,
+          protocol: 'TCP',
+        }, bb.service.spec.ports),
+      }],
+    },
+  },
+
   service: {
     apiVersion: 'v1',
     kind: 'Service',

jsonnet/kube-prometheus/components/kube-state-metrics.libsonnet

@@ -124,6 +124,30 @@ function(params) (import 'github.com/kubernetes/kube-state-metrics/jsonnet/kube-
     image: ksm._config.kubeRbacProxyImage,
   }),
 
+  networkPolicy: {
+    apiVersion: 'networking.k8s.io/v1',
+    kind: 'NetworkPolicy',
+    metadata: ksm.service.metadata,
+    spec: {
+      podSelector: {
+        matchLabels: ksm._config.selectorLabels,
+      },
+      ingress: [{
+        from: [{
+          podSelector: {
+            matchLabels: {
+              'app.kubernetes.io/name': 'prometheus',
+            },
+          },
+        }],
+        ports: std.map(function(o) {
+          port: o.port,
+          protocol: 'TCP',
+        }, ksm.service.spec.ports),
+      }],
+    },
+  },
+
   deployment+: {
     spec+: {
       template+: {

jsonnet/kube-prometheus/components/node-exporter.libsonnet

@@ -160,6 +160,30 @@ function(params) {
     },
   },
 
+  networkPolicy: {
+    apiVersion: 'networking.k8s.io/v1',
+    kind: 'NetworkPolicy',
+    metadata: ne.service.metadata,
+    spec: {
+      podSelector: {
+        matchLabels: ne._config.selectorLabels,
+      },
+      ingress: [{
+        from: [{
+          podSelector: {
+            matchLabels: {
+              'app.kubernetes.io/name': 'prometheus',
+            },
+          },
+        }],
+        ports: std.map(function(o) {
+          port: o.port,
+          protocol: 'TCP',
+        }, ne.service.spec.ports),
+      }],
+    },
+  },
+
   daemonset:
     local nodeExporter = {
       name: ne._config.name,

jsonnet/kube-prometheus/components/prometheus-adapter.libsonnet

@@ -206,6 +206,21 @@ function(params) {
     },
   },
 
+  networkPolicy: {
+    apiVersion: 'networking.k8s.io/v1',
+    kind: 'NetworkPolicy',
+    metadata: pa.service.metadata,
+    spec: {
+      podSelector: {
+        matchLabels: pa._config.selectorLabels,
+      },
+      policyTypes: ['Egress', 'Ingress'],
+      egress: [{}],
+      // Prometheus-adapter needs ingress allowed so HPAs can request metrics from it.
+      ingress: [{}],
+    },
+  },
+
   deployment:
     local c = {
       name: pa._config.name,

manifests/prometheusAdapter-networkPolicy.yaml

@@ -0,0 +1,23 @@
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  labels:
+    app.kubernetes.io/component: metrics-adapter
+    app.kubernetes.io/name: prometheus-adapter
+    app.kubernetes.io/part-of: kube-prometheus
+    app.kubernetes.io/version: 0.9.1
+  name: prometheus-adapter
+  namespace: monitoring
+spec:
+  egress:
+  - {}
+  ingress:
+  - {}
+  podSelector:
+    matchLabels:
+      app.kubernetes.io/component: metrics-adapter
+      app.kubernetes.io/name: prometheus-adapter
+      app.kubernetes.io/part-of: kube-prometheus
+  policyTypes:
+  - Egress
+  - Ingress