feat: improve configuration parsing (#24)

This PR ensures, that the configuration of the garm-operator can be done
with `ENVs`, `Flags` and `Config File (yaml)`

---------

Co-authored-by: bavarianbidi <mario.constanti@mercedes-benz.com>

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
 
       - uses: actions/setup-go@v4
         with:
-          go-version: '1.21.3'
+          go-version: '1.21.4'
 
       - name: make verify
         run: make verify

.github/workflows/foss.yaml

@@ -16,7 +16,7 @@ jobs:
     - name: Set up Go 1.x
       uses: actions/setup-go@v4
       with:
-        go-version: '1.21.3'
+        go-version: '1.21.4'
       id: go
 
     - name: Checkout code

.github/workflows/release.yml

@@ -29,7 +29,7 @@ jobs:
       - run: git fetch --force --tags
       - uses: actions/setup-go@v4
         with:
-          go-version: '1.21.3'
+          go-version: '1.21.4'
 
       - name: Synopsys Detect
         run: |

Dockerfile

@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: MIT
 # Build the manager binary
-FROM golang:1.21.3 as builder
+FROM golang:1.21.4 as builder
 ARG TARGETOS
 ARG TARGETARCH
 

README.md

@@ -61,9 +61,12 @@ export GARM_OPERATOR_VERSION=<garm-operator-version>
 export GARM_SERVER_URL=<garm-server-url> 
 export GARM_SERVER_USERNAME=<garm-server-username>
 export GARM_SERVER_PASSWORD=<garm-server-password>
+export OPERATOR_WATCH_NAMESPACE=<operator-watch-namespace>
 curl -L https://github.com/mercedes-benz/garm-operator/releases/download/${GARM_OPERATOR_VERSION}/garm-operator-all.yaml | envsubst | kubectl apply -f -
 ```
 
+The full configuration parsing documentation can be found in the [configuration parsing guide](./docs/config/configuration-parsing.md)
+
 #### Custom Resources
 
 The CRD documentation can be also seen via [docs.crds.dev](https://doc.crds.dev/github.com/mercedes-benz/garm-operator).

cmd/main.go

@@ -3,24 +3,23 @@
 package main
 
 import (
-	"errors"
-	"flag"
+	"fmt"
 	"os"
-	"time"
 
-	"github.com/spf13/pflag"
+	"gopkg.in/yaml.v2"
 	"k8s.io/apimachinery/pkg/runtime"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
-	"k8s.io/klog/v2"
 	"k8s.io/klog/v2/klogr"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/cache"
 	"sigs.k8s.io/controller-runtime/pkg/healthz"
 
 	garmoperatorv1alpha1 "github.com/mercedes-benz/garm-operator/api/v1alpha1"
 	"github.com/mercedes-benz/garm-operator/internal/controller"
+	"github.com/mercedes-benz/garm-operator/pkg/config"
+	"github.com/mercedes-benz/garm-operator/pkg/flags"
 )
 
 var (
@@ -36,68 +35,45 @@ func init() {
 }
 
 func main() {
-	var (
-		metricsAddr          string
-		enableLeaderElection bool
-		probeAddr            string
-		syncPeriod           time.Duration
-
-		watchNamespace string
-
-		garmServer   string
-		garmUsername string
-		garmPassword string
-	)
-
-	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.DurationVar(&syncPeriod, "sync-period", 5*time.Minute,
-		"The minimum interval at which watched resources are reconciled (e.g. 15m)")
-
-	flag.StringVar(&watchNamespace, "namespace", "",
-		"Namespace that the controller watches to reconcile garm objects. If unspecified, the controller watches for garm objects across all namespaces.")
-
-	flag.StringVar(&garmServer, "garm-server", "", "The address of the GARM server")
-	flag.StringVar(&garmUsername, "garm-username", "", "The username for the GARM server")
-	flag.StringVar(&garmPassword, "garm-password", "", "The password for the GARM server")
-
-	klog.InitFlags(flag.CommandLine)
-	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
-	pflag.Parse()
 	ctrl.SetLogger(klogr.New())
 
-	// configure garm client from environment variables
-	if len(os.Getenv("GARM_SERVER")) > 0 {
-		setupLog.Info("Using garm-server from environment variable")
-		garmServer = os.Getenv("GARM_SERVER")
-	}
-	if len(os.Getenv("GARM_USERNAME")) > 0 {
-		setupLog.Info("Using garm-username from environment variable")
-		garmUsername = os.Getenv("GARM_USERNAME")
-	}
-	if len(os.Getenv("GARM_PASSWORD")) > 0 {
-		setupLog.Info("Using garm-password from environment variable")
-		garmPassword = os.Getenv("GARM_PASSWORD")
+	// initiate flags
+	f := flags.InitiateFlags()
+
+	// retrieve config flag value for GenerateConfig() function
+	configFile := f.Lookup("config").Value.String()
+
+	// call GenerateConfig() function from config package
+	if err := config.GenerateConfig(f, configFile); err != nil {
+		setupLog.Error(err, "failed to read config")
+		os.Exit(1)
 	}
-	if len(os.Getenv("WATCH_NAMESPACE")) > 0 {
-		setupLog.Info("using watch-namespace from environment variable")
-		watchNamespace = os.Getenv("WATCH_NAMESPACE")
+
+	// check if dry-run flag is set to true
+	dryRun, _ := f.GetBool("dry-run")
+
+	// perform dry-run if enabled and print out the generated Config as yaml
+	if dryRun {
+		yamlConfig, err := yaml.Marshal(config.Config)
+		if err != nil {
+			setupLog.Error(err, "failed to marshal config as yaml")
+			os.Exit(1)
+		}
+		fmt.Printf("generated Config as yaml:\n%s\n", yamlConfig)
+		os.Exit(0)
 	}
 
 	var watchNamespaces []string
-	if watchNamespace != "" {
-		watchNamespaces = []string{watchNamespace}
+	if config.Config.Operator.WatchNamespace != "" {
+		watchNamespaces = []string{config.Config.Operator.WatchNamespace}
 	}
 
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
 		Scheme:                 scheme,
-		MetricsBindAddress:     metricsAddr,
+		MetricsBindAddress:     config.Config.Operator.MetricsBindAddress,
 		Port:                   9443,
-		HealthProbeBindAddress: probeAddr,
-		LeaderElection:         enableLeaderElection,
+		HealthProbeBindAddress: config.Config.Operator.HealthProbeBindAddress,
+		LeaderElection:         config.Config.Operator.LeaderElection,
 		LeaderElectionID:       "b608d8b3.mercedes-benz.com",
 		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
 		// when the Manager ends. This requires the binary to immediately end when the
@@ -113,38 +89,25 @@ func main() {
 		//
 		// Default Sync Period = 10 hours.
 		// Set default via flag to 5 minutes
-		SyncPeriod: &syncPeriod,
+		SyncPeriod: &config.Config.Operator.SyncPeriod,
 		Cache: cache.Options{
 			Namespaces: watchNamespaces,
-			SyncPeriod: &syncPeriod,
+			SyncPeriod: &config.Config.Operator.SyncPeriod,
 		},
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")
 		os.Exit(1)
 	}
 
-	if garmServer == "" {
-		setupLog.Error(errors.New("unable to fetch garm server from either flag or os_env"), "unable to start manager")
-		os.Exit(1)
-	}
-	if garmUsername == "" {
-		setupLog.Error(errors.New("unable to fetch garm username from either flag or os_env"), "unable to start manager")
-		os.Exit(1)
-	}
-	if garmPassword == "" {
-		setupLog.Error(errors.New("unable to fetch garm password from either flag or os_env"), "unable to start manager")
-		os.Exit(1)
-	}
-
 	if err = (&controller.EnterpriseReconciler{
 		Client:   mgr.GetClient(),
 		Scheme:   mgr.GetScheme(),
 		Recorder: mgr.GetEventRecorderFor("enterprise-controller"),
 
-		BaseURL:  garmServer,
-		Username: garmUsername,
-		Password: garmPassword,
+		BaseURL:  config.Config.Garm.Server,
+		Username: config.Config.Garm.Username,
+		Password: config.Config.Garm.Password,
 	}).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "Enterprise")
 		os.Exit(1)
@@ -154,37 +117,35 @@ func main() {
 		Scheme:   mgr.GetScheme(),
 		Recorder: mgr.GetEventRecorderFor("pool-controller"),
 
-		BaseURL:  garmServer,
-		Username: garmUsername,
-		Password: garmPassword,
+		BaseURL:  config.Config.Garm.Server,
+		Username: config.Config.Garm.Username,
+		Password: config.Config.Garm.Password,
 	}).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "Pool")
 		os.Exit(1)
 	}
 
-	if os.Getenv("CREATE_WEBHOOK") == "true" {
-		if err = (&garmoperatorv1alpha1.Pool{}).SetupWebhookWithManager(mgr); err != nil {
-			setupLog.Error(err, "unable to create webhook", "webhook", "Pool")
-			os.Exit(1)
-		}
-		if err = (&garmoperatorv1alpha1.Image{}).SetupWebhookWithManager(mgr); err != nil {
-			setupLog.Error(err, "unable to create webhook", "webhook", "Image")
-			os.Exit(1)
-		}
-		if err = (&garmoperatorv1alpha1.Repository{}).SetupWebhookWithManager(mgr); err != nil {
-			setupLog.Error(err, "unable to create webhook", "webhook", "Repository")
-			os.Exit(1)
-		}
+	if err = (&garmoperatorv1alpha1.Pool{}).SetupWebhookWithManager(mgr); err != nil {
+		setupLog.Error(err, "unable to create webhook", "webhook", "Pool")
+		os.Exit(1)
+	}
+	if err = (&garmoperatorv1alpha1.Image{}).SetupWebhookWithManager(mgr); err != nil {
+		setupLog.Error(err, "unable to create webhook", "webhook", "Image")
+		os.Exit(1)
+	}
+	if err = (&garmoperatorv1alpha1.Repository{}).SetupWebhookWithManager(mgr); err != nil {
+		setupLog.Error(err, "unable to create webhook", "webhook", "Repository")
+		os.Exit(1)
 	}
 
 	if err = (&controller.OrganizationReconciler{
 		Client:   mgr.GetClient(),
 		Scheme:   mgr.GetScheme(),
 		Recorder: mgr.GetEventRecorderFor("organization-controller"),
 
-		BaseURL:  garmServer,
-		Username: garmUsername,
-		Password: garmPassword,
+		BaseURL:  config.Config.Garm.Server,
+		Username: config.Config.Garm.Username,
+		Password: config.Config.Garm.Password,
 	}).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "Organization")
 		os.Exit(1)
@@ -195,9 +156,9 @@ func main() {
 		Scheme:   mgr.GetScheme(),
 		Recorder: mgr.GetEventRecorderFor("repository-controller"),
 
-		BaseURL:  garmServer,
-		Username: garmUsername,
-		Password: garmPassword,
+		BaseURL:  config.Config.Garm.Server,
+		Username: config.Config.Garm.Username,
+		Password: config.Config.Garm.Password,
 	}).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "Repository")
 		os.Exit(1)

config/manager/manager.yaml

@@ -50,14 +50,8 @@ spec:
         - --garm-server=$GARM_SERVER_URL
         - --garm-username=$GARM_SERVER_USERNAME
         - --garm-password=$GARM_SERVER_PASSWORD
+        - --operator-watch-namespace=$OPERATOR_WATCH_NAMESPACE
         image: controller:latest
-        env:
-        - name: CREATE_WEBHOOK
-          value: "true"
-        - name: WATCH_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
         name: manager
         securityContext:
           allowPrivilegeEscalation: false