Add validation/mutating webhook server for Fission custom resources (#2608)

* add webhook server
* add metrics port
* Add self-signed cert generation in helm chart for webhooks (#2611)
* remove cert-manager installation
* update fission webhook charts
* remove extra cluster role
* add mutating webhook for pkg creation
* Service name and bundle fixes (#2614)
* caBundle templating
* Rename fission.svc to fission-webhook.svc
* update package build status

Co-authored-by: shaunak_deshmukh <shaunak@infracloud.io>

pkg/webhook/admission-webhook.go

@@ -0,0 +1,85 @@
+/*
+Copyright 2022.
+
+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 webhook
+
+import (
+	"context"
+	"os"
+
+	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
+	// to ensure that exec-entrypoint and run can make use of them.
+
+	"go.uber.org/zap"
+	_ "k8s.io/client-go/plugin/pkg/client/auth"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+
+	v1 "github.com/fission/fission/pkg/apis/core/v1"
+	"github.com/fission/fission/pkg/generated/clientset/versioned/scheme"
+	//+kubebuilder:scaffold:imports
+)
+
+type WebhookInjector interface {
+	SetupWebhookWithManager(mgr manager.Manager) error
+}
+
+func Start(ctx context.Context, logger *zap.Logger, port int) (err error) {
+
+	wLogger := logger.Named("webhook")
+
+	metricsAddr := os.Getenv("METRICS_ADDR")
+	if metricsAddr == "" {
+		metricsAddr = ":8080"
+	}
+	// Setup a Manager
+	mgr, err := manager.New(config.GetConfigOrDie(), manager.Options{
+		Scheme:             scheme.Scheme,
+		Port:               port,
+		MetricsBindAddress: metricsAddr,
+	})
+	if err != nil {
+		wLogger.Error("unable to set up overall controller manager", zap.Error(err))
+		return err
+	}
+
+	// Setup webhooks
+
+	webhookInjectors := []WebhookInjector{
+		&v1.CanaryConfig{},
+		&v1.Environment{},
+		&v1.Package{},
+		&v1.Function{},
+		&v1.HTTPTrigger{},
+		&v1.MessageQueueTrigger{},
+		&v1.TimeTrigger{},
+		&v1.KubernetesWatchTrigger{},
+	}
+
+	for _, injector := range webhookInjectors {
+		if err := injector.SetupWebhookWithManager(mgr); err != nil {
+			wLogger.Error("unable to create webhook", zap.Error(err))
+			return err
+		}
+	}
+
+	wLogger.Info("starting manager")
+	if err := mgr.Start(ctx); err != nil {
+		wLogger.Error("unable to run manager", zap.Error(err))
+		return err
+	}
+	return nil
+}