[SREP-609] POC adding a Golang scripts

Dockerfile

@@ -122,6 +122,15 @@ RUN OUT_DIR=/out make hypershift
 # Make binaries executable
 RUN chmod -R +x /out
 
+# build the golang scripts
+COPY goapp /goapp
+COPY scripts /scripts
+WORKDIR /goapp
+RUN go build -o /out/goapp main.go
+RUN chmod -R +x /out
+
+
+
 FROM registry.access.redhat.com/ubi8/ubi:8.9
 RUN  yum -y install --disableplugin=subscription-manager \
      python3.11 python3.11-pip jq openssh-clients sshpass \
@@ -133,6 +142,7 @@ COPY --from=build-stage0 /aws/bin/  /usr/local/bin
 COPY --from=build-stage0 /usr/local/aws-cli /usr/local/aws-cli
 COPY --from=build-stage0 /out/hypershift /usr/local/bin
 COPY --from=build-stage0 /out/ocm /usr/local/bin
+COPY --from=build-stage0 /out/goapp /usr/local/bin
 COPY scripts /managed-scripts
 
 # Install python packages

goapp/cmd/cmd.go

@@ -0,0 +1,22 @@
+// Assisted by GenAI
+
+package cmd
+
+import (
+	"github.com/openshift/managed-scripts/goapp/internal/cli"
+)
+
+var moduleRegistry map[string]cli.CommandModule
+
+// Allow runtime injection of module registry
+func SetModuleRegistry(m map[string]cli.CommandModule) {
+	moduleRegistry = m
+}
+
+// Add all registered modules to RootCmd using cli.WrapModule
+func AddModuleCommands() {
+	for _, module := range moduleRegistry {
+		cmd := cli.WrapModule(module) // This builds the Cobra command with flag/env/param loading
+		RootCmd.AddCommand(cmd)
+	}
+}

goapp/cmd/root.go

@@ -0,0 +1,19 @@
+package cmd
+
+import (
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var RootCmd = &cobra.Command{
+	Use:   "goapp",
+	Short: "entry point for running golang managed-scripts",
+}
+
+func Execute() {
+	if err := RootCmd.Execute(); err != nil {
+		os.Exit(1)
+	}
+}
+

goapp/go.mod

@@ -0,0 +1,62 @@
+module github.com/openshift/managed-scripts/goapp
+
+go 1.24.1
+
+require (
+	github.com/spf13/cobra v1.9.1
+	github.com/spf13/viper v1.20.1
+	k8s.io/api v0.33.1
+	k8s.io/apimachinery v0.33.1
+	k8s.io/client-go v0.33.1
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.11.0 // indirect
+	github.com/fsnotify/fsnotify v1.8.0 // indirect
+	github.com/fxamacker/cbor/v2 v2.7.0 // indirect
+	github.com/go-logr/logr v1.4.2 // indirect
+	github.com/go-openapi/jsonpointer v0.21.0 // indirect
+	github.com/go-openapi/jsonreference v0.20.2 // indirect
+	github.com/go-openapi/swag v0.23.0 // indirect
+	github.com/go-viper/mapstructure/v2 v2.2.1 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/google/gnostic-models v0.6.9 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.3 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/sagikazarmark/locafero v0.7.0 // indirect
+	github.com/sourcegraph/conc v0.3.0 // indirect
+	github.com/spf13/afero v1.12.0 // indirect
+	github.com/spf13/cast v1.7.1 // indirect
+	github.com/spf13/pflag v1.0.6 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
+	github.com/x448/float16 v0.8.4 // indirect
+	go.uber.org/atomic v1.9.0 // indirect
+	go.uber.org/multierr v1.9.0 // indirect
+	golang.org/x/net v0.38.0 // indirect
+	golang.org/x/oauth2 v0.27.0 // indirect
+	golang.org/x/sys v0.31.0 // indirect
+	golang.org/x/term v0.30.0 // indirect
+	golang.org/x/text v0.23.0 // indirect
+	golang.org/x/time v0.9.0 // indirect
+	google.golang.org/protobuf v1.36.5 // indirect
+	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/klog/v2 v2.130.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20250318190949-c8a335a9a2ff // indirect
+	k8s.io/utils v0.0.0-20241104100929-3ea5e8cea738 // indirect
+	sigs.k8s.io/json v0.0.0-20241010143419-9aa6b5e7a4b3 // indirect
+	sigs.k8s.io/randfill v1.0.0 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.6.0 // indirect
+	sigs.k8s.io/yaml v1.4.0 // indirect
+)

goapp/internal/cli/cli.go

@@ -0,0 +1,107 @@
+// Assisted by GenAI
+
+package cli
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+type Params interface{}
+
+type CommandModule interface {
+	Name() string    // return the name of the subcommand (script).
+	Summary() string // return a short summary of what this subcommand does.
+	Params() Params  // return a pointer to a struct of needed parameters.
+	Execute() error  // main logic goes here.
+}
+
+func WrapModule(module CommandModule) *cobra.Command {
+	params := module.Params()
+
+	cmd := &cobra.Command{
+		Use:   module.Name(),
+		Short: module.Summary(),
+		PreRunE: func(cmd *cobra.Command, args []string) error {
+			return LoadParamsFromViper(params)
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return module.Execute()
+		},
+	}
+
+	BindFlagsWithViper(cmd, params)
+	return cmd
+}
+
+func BindFlagsWithViper(cmd *cobra.Command, params Params) {
+	if params == nil {
+		return // nothing to bind
+	}
+
+	v := reflect.ValueOf(params).Elem()
+	t := v.Type()
+
+	viper.AutomaticEnv()
+	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
+
+	for i := 0; i < t.NumField(); i++ {
+		field := t.Field(i)
+		flag := field.Tag.Get("flag")
+		env := field.Tag.Get("env")
+		usage := field.Tag.Get("usage")
+		def := field.Tag.Get("default")
+
+		if flag == "" {
+			flag = strings.ToLower(field.Name)
+		}
+		if env == "" {
+			env = strings.ToUpper(flag)
+		}
+
+		key := flag // same key for flag/env/viper
+
+		switch field.Type.Kind() {
+		case reflect.String:
+			cmd.Flags().String(flag, def, usage)
+			viper.BindPFlag(key, cmd.Flags().Lookup(flag))
+			viper.BindEnv(key, env)
+		case reflect.Bool:
+			cmd.Flags().Bool(flag, def == "true", usage)
+			viper.BindPFlag(key, cmd.Flags().Lookup(flag))
+			viper.BindEnv(key, env)
+		}
+	}
+}
+
+func LoadParamsFromViper(params Params) error {
+	if params == nil {
+		return nil // nothing to load
+	}
+
+	v := reflect.ValueOf(params).Elem()
+	t := v.Type()
+
+	for i := 0; i < t.NumField(); i++ {
+		field := t.Field(i)
+		key := field.Tag.Get("flag")
+		if key == "" {
+			key = strings.ToLower(field.Name)
+		}
+		val := v.Field(i)
+
+		switch field.Type.Kind() {
+		case reflect.String:
+			val.SetString(viper.GetString(key))
+		case reflect.Bool:
+			val.SetBool(viper.GetBool(key))
+		default:
+			return fmt.Errorf("unsupported param type: %s", field.Type.Kind())
+		}
+	}
+	return nil
+}

goapp/internal/cli/cli_test.go

@@ -0,0 +1,34 @@
+// Assisted by GenAI
+package cli
+
+import (
+	"testing"
+
+	"github.com/spf13/cobra"
+)
+
+func TestBindFlagsWithViper_NilParams(t *testing.T) {
+	cmd := &cobra.Command{
+		Use: "test-cmd",
+	}
+
+	// Prevent panic when nil is passed
+	defer func() {
+		if r := recover(); r != nil {
+			t.Errorf("BindFlagsWithViper panicked when params was nil: %v", r)
+		}
+	}()
+
+	BindFlagsWithViper(cmd, nil)
+
+	if cmd.Flags().HasFlags() {
+		t.Errorf("expected no flags to be bound when params is nil")
+	}
+}
+
+func TestLoadParamsFromViper_NilParams(t *testing.T) {
+	err := LoadParamsFromViper(nil)
+	if err != nil {
+		t.Errorf("expected no error when loading nil params, got: %v", err)
+	}
+}

goapp/internal/registry/registry.go

@@ -0,0 +1,20 @@
+// Assisted by GenAI
+
+package registry
+
+// Contributor TODO: import your package here
+import (
+	"github.com/openshift/managed-scripts/goapp/internal/cli"
+	pods "github.com/openshift/managed-scripts/goapp/pkg/ceepod"
+	nodes "github.com/openshift/managed-scripts/goapp/pkg/srepnode"
+	"github.com/openshift/managed-scripts/goapp/pkg/utils"
+)
+
+// Contributor TODO: register your module here.
+// clientFn provides a kube client, you can use it if your code needs to interact with the cluster.
+func NewRegistry(clientFn utils.ClientFactoryFunc) map[string]cli.CommandModule {
+	return map[string]cli.CommandModule{
+		"getnodes": nodes.NewNodeModule(clientFn),
+		"getpods":  pods.NewPodModule(clientFn),
+	}
+}

goapp/main.go

@@ -0,0 +1,20 @@
+// Assisted by GenAI
+package main
+
+import (
+	"github.com/openshift/managed-scripts/goapp/cmd"
+	"github.com/openshift/managed-scripts/goapp/internal/registry"
+	"github.com/openshift/managed-scripts/goapp/pkg/utils"
+)
+
+func main() {
+	// utils.GetOrInitKubeClient is for lazy load
+	// it will only load the kube client when it actual gets called
+	// so that kubeconfig is not a hard requirement for running the root command
+	modules := registry.NewRegistry(utils.GetOrInitKubeClient)
+
+	cmd.SetModuleRegistry(modules)
+	cmd.AddModuleCommands()
+
+	cmd.Execute()
+}

goapp/pkg/ceepod

@@ -0,0 +1 @@
+../../scripts/CEE/get-pods

goapp/pkg/srepnode

@@ -0,0 +1 @@
+../../scripts/SREP/get-nodes

goapp/pkg/utils/kubeclient.go

@@ -0,0 +1,37 @@
+// Assisted-by Generative AI.
+
+package utils
+
+import (
+	"sync"
+
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+)
+
+type ClientFactoryFunc func() (kubernetes.Interface, error)
+
+var (
+	clientOnce   sync.Once
+	cachedClient kubernetes.Interface
+	clientErr    error
+)
+
+func GetOrInitKubeClient() (kubernetes.Interface, error) {
+	clientOnce.Do(func() {
+		cachedClient, clientErr = GetKubeClient(NewDefaultConfigLoader())
+	})
+	return cachedClient, clientErr
+}
+
+type ConfigLoader interface {
+	ClientConfig() (*rest.Config, error)
+}
+
+func GetKubeClient(loader ConfigLoader) (*kubernetes.Clientset, error) {
+	config, err := loader.ClientConfig()
+	if err != nil {
+		return nil, err
+	}
+	return kubernetes.NewForConfig(config)
+}

goapp/pkg/utils/kubeclient_loader.go

@@ -0,0 +1,13 @@
+// Assisted-by Generative AI.
+
+package utils
+
+import (
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+func NewDefaultConfigLoader() ConfigLoader {
+	loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
+	overrides := &clientcmd.ConfigOverrides{}
+	return clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, overrides)
+}