Add PrometheusSource webhook

prometheus/cmd/webhook/main.go

@@ -0,0 +1,105 @@
+/*
+Copyright 2020 The Knative Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"context"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	sourcev1alpha1 "knative.dev/eventing-contrib/prometheus/pkg/apis/sources/v1alpha1"
+	"knative.dev/eventing/pkg/logconfig"
+	"knative.dev/pkg/configmap"
+	"knative.dev/pkg/controller"
+	"knative.dev/pkg/injection/sharedmain"
+	"knative.dev/pkg/signals"
+	"knative.dev/pkg/webhook"
+	"knative.dev/pkg/webhook/certificates"
+	"knative.dev/pkg/webhook/resourcesemantics"
+	"knative.dev/pkg/webhook/resourcesemantics/defaulting"
+	"knative.dev/pkg/webhook/resourcesemantics/validation"
+)
+
+var types = map[schema.GroupVersionKind]resourcesemantics.GenericCRD{
+	sourcev1alpha1.SchemeGroupVersion.WithKind("PrometheusSource"): &sourcev1alpha1.PrometheusSource{},
+}
+
+var callbacks = map[schema.GroupVersionKind]validation.Callback{}
+
+func NewDefaultingAdmissionController(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
+	return defaulting.NewAdmissionController(ctx,
+
+		// Name of the resource webhook.
+		"defaulting.webhook.prometheus.sources.knative.dev",
+
+		// The path on which to serve the webhook.
+		"/defaulting",
+
+		// The resources to validate and default.
+		types,
+
+		// A function that infuses the context passed to Validate/SetDefaults with custom metadata.
+		func(ctx context.Context) context.Context {
+			// Here is where you would infuse the context with state
+			// (e.g. attach a store with configmap data)
+			return ctx
+		},
+
+		// Whether to disallow unknown fields.
+		true,
+	)
+}
+
+func NewValidationAdmissionController(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
+	return validation.NewAdmissionController(ctx,
+
+		// Name of the resource webhook.
+		"validation.webhook.prometheus.sources.knative.dev",
+
+		// The path on which to serve the webhook.
+		"/resource-validation",
+
+		// The resources to validate and default.
+		types,
+
+		// A function that infuses the context passed to Validate/SetDefaults with custom metadata.
+		func(ctx context.Context) context.Context {
+			// Here is where you would infuse the context with state
+			// (e.g. attach a store with configmap data)
+			return ctx
+		},
+
+		// Whether to disallow unknown fields.
+		true,
+
+		// Extra validating callbacks to be applied to resources.
+		callbacks,
+	)
+}
+
+func main() {
+	ctx := webhook.WithOptions(signals.NewContext(), webhook.Options{
+		ServiceName: logconfig.WebhookName(),
+		Port:        8443,
+		SecretName:  "prometheus-source-webhook-certs",
+	})
+
+	sharedmain.WebhookMainWithContext(ctx, logconfig.WebhookName(),
+		certificates.NewController,
+		NewDefaultingAdmissionController,
+		NewValidationAdmissionController,
+	)
+}

prometheus/config/200-serviceaccount.yaml

@@ -17,3 +17,13 @@ kind: ServiceAccount
 metadata:
   name: prometheus-controller-manager
   namespace: knative-sources
+
+---
+
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: prometheus-source-webhook
+  namespace: knative-sources
+  labels:
+    contrib.eventing.knative.dev/release: devel

prometheus/config/202-clusterrolebinding.yaml

@@ -42,3 +42,19 @@ roleRef:
   kind: ClusterRole
   name: addressable-resolver
 
+---
+
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: eventing-sources-prometheus-webhook
+  labels:
+    contrib.eventing.knative.dev/release: devel
+subjects:
+  - kind: ServiceAccount
+    name: prometheus-source-webhook
+    namespace: knative-sources
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: prometheus-source-webhook

prometheus/config/203-webhook-clusterrole.yaml

@@ -0,0 +1,122 @@
+# Copyright 2020 The Knative Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: prometheus-source-webhook
+  labels:
+    contrib.eventing.knative.dev/release: devel
+rules:
+  # Sources admin
+  - apiGroups:
+      - sources.knative.dev
+    resources:
+      - prometheussources
+    verbs: &everything
+      - get
+      - list
+      - watch
+      - create
+      - update
+      - patch
+      - delete
+
+  # Sources finalizer
+  - apiGroups:
+      - sources.knative.dev
+    resources:
+      - prometheussources/finalizers
+    verbs: *everything
+
+  # Source statuses update
+  - apiGroups:
+      - sources.knative.dev
+    resources:
+      - prometheussources/status
+    verbs:
+      - get
+      - update
+      - patch
+
+  # Deployments admin
+  - apiGroups:
+      - apps
+    resources:
+      - deployments
+    verbs: *everything
+
+  # Knative Services admin
+  - apiGroups:
+      - serving.knative.dev
+    resources:
+      - services
+    verbs: *everything
+
+  # Secrets read
+  - apiGroups:
+      - ""
+    resources:
+      - secrets
+      - services
+    verbs:
+      - get
+      - list
+      - watch
+
+  # Namespace labelling for webhook
+  - apiGroups:
+      - ""
+    resources:
+      - namespaces
+    verbs:
+      - get
+      - list
+      - watch
+      - patch
+
+  # Events admin
+  - apiGroups:
+      - ""
+    resources:
+      - events
+      - configmaps
+    verbs: *everything
+
+  # EventTypes admin
+  - apiGroups:
+      - eventing.knative.dev
+    resources:
+      - eventtypes
+    verbs: *everything
+
+  # For manipulating certs into secrets.
+  - apiGroups:
+      - ""
+    resources:
+      - "secrets"
+    verbs:
+      - "get"
+      - "create"
+      - "update"
+      - "list"
+      - "watch"
+
+  # For actually registering our webhook.
+  - apiGroups:
+      - "admissionregistration.k8s.io"
+    resources:
+      - "mutatingwebhookconfigurations"
+      - "validatingwebhookconfigurations"
+    verbs: *everything

prometheus/config/500-webhook-config.yaml

@@ -0,0 +1,45 @@
+# Copyright 2020 The Knative Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+apiVersion: admissionregistration.k8s.io/v1beta1
+kind: MutatingWebhookConfiguration
+metadata:
+  name: defaulting.webhook.prometheus.sources.knative.dev
+  labels:
+    contrib.eventing.knative.dev/release: devel
+webhooks:
+  - admissionReviewVersions:
+      - v1beta1
+    clientConfig:
+      service:
+        name: prometheus-source-webhook
+        namespace: knative-sources
+    failurePolicy: Fail
+    name: defaulting.webhook.prometheus.sources.knative.dev
+---
+apiVersion: admissionregistration.k8s.io/v1beta1
+kind: ValidatingWebhookConfiguration
+metadata:
+  name: validation.webhook.prometheus.sources.knative.dev
+  labels:
+    contrib.eventing.knative.dev/release: devel
+webhooks:
+  - admissionReviewVersions:
+      - v1beta1
+    clientConfig:
+      service:
+        name: prometheus-source-webhook
+        namespace: knative-sources
+    failurePolicy: Fail
+    name: validation.webhook.prometheus.sources.knative.dev

prometheus/config/500-webhook.yaml

@@ -0,0 +1,80 @@
+# Copyright 2020 The Knative Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+apiVersion: v1
+kind: Secret
+metadata:
+  name: prometheus-source-webhook-certs
+  namespace: knative-sources
+  labels:
+    contrib.eventing.knative.dev/release: devel
+# The data is populated at install time.
+
+---
+
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: prometheus-source-webhook
+  namespace: knative-sources
+  labels:
+    contrib.eventing.knative.dev/release: devel
+spec:
+  replicas: 1
+  selector:
+    matchLabels: &labels
+      app: prometheus-source-webhook
+      role: prometheus-source-webhook
+  template:
+    metadata:
+      annotations:
+        sidecar.istio.io/inject: "false"
+      labels: *labels
+    spec:
+      serviceAccountName: prometheus-source-webhook
+      containers:
+        - name: prometheus-source-webhook
+          terminationMessagePolicy: FallbackToLogsOnError
+          image: ko://knative.dev/eventing-contrib/prometheus/cmd/webhook
+          env:
+            - name: SYSTEM_NAMESPACE
+              valueFrom:
+                fieldRef:
+                  fieldPath: metadata.namespace
+            - name: CONFIG_LOGGING_NAME
+              value: config-logging
+            - name: METRICS_DOMAIN
+              value: knative.dev/eventing
+            - name: WEBHOOK_NAME
+              value: prometheus-source-webhook
+          ports:
+            - containerPort: 9090
+              name: metrics
+          # TODO set proper resource limits.
+---
+apiVersion: v1
+kind: Service
+metadata:
+  labels:
+    eventing.knative.dev/release: devel
+    role: prometheus-source-webhook
+  name: prometheus-source-webhook
+  namespace: knative-sources
+spec:
+  ports:
+    - name: https-webhook
+      port: 443
+      targetPort: 8443
+  selector:
+    role: prometheus-source-webhook