main.go

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright (c) 2024 Matthew Penner

package main

import (
	"crypto/tls"
	"flag"
	"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.
	_ "k8s.io/client-go/plugin/pkg/client/auth"
	gatewayv1 "sigs.k8s.io/gateway-api/apis/v1"
	gatewayv1alpha2 "sigs.k8s.io/gateway-api/apis/v1alpha2"
	gatewayv1alpha3 "sigs.k8s.io/gateway-api/apis/v1alpha3"
	gatewayv1beta1 "sigs.k8s.io/gateway-api/apis/v1beta1"

	"k8s.io/apimachinery/pkg/runtime"
	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/healthz"
	"sigs.k8s.io/controller-runtime/pkg/log/zap"
	metricsserver "sigs.k8s.io/controller-runtime/pkg/metrics/server"
	"sigs.k8s.io/controller-runtime/pkg/webhook"

	//+kubebuilder:scaffold:imports

	"github.com/caddyserver/gateway/internal/controller"
)

var (
	scheme   = runtime.NewScheme()
	setupLog = ctrl.Log.WithName("setup")
)

func init() {
	utilruntime.Must(clientgoscheme.AddToScheme(scheme))

	utilruntime.Must(gatewayv1.Install(scheme))
	utilruntime.Must(gatewayv1alpha2.Install(scheme))
	utilruntime.Must(gatewayv1alpha3.Install(scheme))
	utilruntime.Must(gatewayv1beta1.Install(scheme))
	//+kubebuilder:scaffold:scheme
}

func main() {
	var metricsAddr string
	var enableLeaderElection bool
	var probeAddr string
	var secureMetrics bool
	var enableHTTP2 bool
	flag.StringVar(&metricsAddr, "metrics-bind-address", ":8080", "The address the metric endpoint binds to.")
	flag.StringVar(&probeAddr, "health-probe-bind-address", ":8081", "The address the probe endpoint binds to.")
	flag.BoolVar(&enableLeaderElection, "leader-elect", false,
		"Enable leader election for controller manager. "+
			"Enabling this will ensure there is only one active controller manager.")
	flag.BoolVar(&secureMetrics, "metrics-secure", false,
		"If set the metrics endpoint is served securely")
	flag.BoolVar(&enableHTTP2, "enable-http2", false,
		"If set, HTTP/2 will be enabled for the metrics and webhook servers")
	opts := zap.Options{
		Development: true,
	}
	opts.BindFlags(flag.CommandLine)
	flag.Parse()

	ctrl.SetLogger(zap.New(zap.UseFlagOptions(&opts)))

	// if the enable-http2 flag is false (the default), http/2 should be disabled
	// due to its vulnerabilities. More specifically, disabling http/2 will
	// prevent from being vulnerable to the HTTP/2 Stream Cancellation and
	// Rapid Reset CVEs. For more information see:
	// - https://github.com/advisories/GHSA-qppj-fm5r-hxr3
	// - https://github.com/advisories/GHSA-4374-p667-p6c8
	disableHTTP2 := func(c *tls.Config) {
		setupLog.Info("disabling http/2")
		c.NextProtos = []string{"http/1.1"}
	}

	tlsOpts := []func(*tls.Config){}
	if !enableHTTP2 {
		tlsOpts = append(tlsOpts, disableHTTP2)
	}

	webhookServer := webhook.NewServer(webhook.Options{
		TLSOpts: tlsOpts,
	})

	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
		Scheme: scheme,
		Metrics: metricsserver.Options{
			BindAddress:   metricsAddr,
			SecureServing: secureMetrics,
			TLSOpts:       tlsOpts,
		},
		WebhookServer:          webhookServer,
		HealthProbeBindAddress: probeAddr,
		LeaderElection:         enableLeaderElection,
		LeaderElectionID:       "657d83d7.caddyserver.com",

		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
		// when the Manager ends. This requires the binary to immediately end when the
		// Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
		// speeds up voluntary leader transitions as the new leader don't have to wait
		// LeaseDuration time first.
		//
		// In the default scaffold provided, the program ends immediately after
		// the manager stops, so would be fine to enable this option. However,
		// if you are doing or is intended to do any operation such as perform cleanups
		// after the manager stops then its usage might be unsafe.
		LeaderElectionReleaseOnCancel: true,
	})
	if err != nil {
		setupLog.Error(err, "unable to start manager")
		os.Exit(1)
		return
	}

	client := mgr.GetClient()
	scheme := mgr.GetScheme()
	recorder := mgr.GetEventRecorderFor("caddy-gateway")

	if err = (&controller.GatewayReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "Gateway")
		os.Exit(1)
		return
	}
	if err = (&controller.GatewayClassReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "GatewayClass")
		os.Exit(1)
		return
	}
	//if err = (&controller.GRPCRouteReconciler{
	//	Client:   client,
	//	Scheme:   scheme,
	//	Recorder: recorder,
	//}).SetupWithManager(mgr); err != nil {
	//	setupLog.Error(err, "unable to create controller", "controller", "GRPCRoute")
	//	os.Exit(1)
	//	return
	//}
	if err = (&controller.HTTPRouteReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "HTTPRoute")
		os.Exit(1)
		return
	}
	if err = (&controller.TCPRouteReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "TCPRoute")
		os.Exit(1)
		return
	}
	if err = (&controller.TLSRouteReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "TLSRoute")
		os.Exit(1)
		return
	}
	if err = (&controller.UDPRouteReconciler{
		Client:   client,
		Scheme:   scheme,
		Recorder: recorder,
	}).SetupWithManager(mgr); err != nil {
		setupLog.Error(err, "unable to create controller", "controller", "UDPRoute")
		os.Exit(1)
		return
	}
	//+kubebuilder:scaffold:builder

	if err := mgr.AddHealthzCheck("healthz", healthz.Ping); err != nil {
		setupLog.Error(err, "unable to set up health check")
		os.Exit(1)
	}
	if err := mgr.AddReadyzCheck("readyz", healthz.Ping); err != nil {
		setupLog.Error(err, "unable to set up ready check")
		os.Exit(1)
	}

	setupLog.Info("starting manager")
	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
		setupLog.Error(err, "problem running manager")
		os.Exit(1)
	}
}