internal/pkg/commands/loglevel.go - voltctl - Gitiles

 /*
  * Copyright 2019-present Ciena Corporation
  *
  * 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 commands

 import (
 	"context"
 	"fmt"
 	"github.com/fullstorydev/grpcurl"
 	flags "github.com/jessevdk/go-flags"
 	"github.com/jhump/protoreflect/dynamic"
 	"github.com/opencord/voltctl/pkg/format"
 	"github.com/opencord/voltctl/pkg/model"
 	"google.golang.org/grpc"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/clientcmd"
 	"strings"
 )

 type SetLogLevelOutput struct {
 	ComponentName string
 	Status        string
 	Error         string
 }

 type SetLogLevelOpts struct {
 	OutputOptions
 	Package string `short:"p" long:"package" description:"Package name to set log level"`
 	Args    struct {
 		Level     string
 		Component []string
 	} `positional-args:"yes" required:"yes"`
 }

 type GetLogLevelsOpts struct {
 	ListOutputOptions
 	Args struct {
 		Component []string
 	} `positional-args:"yes" required:"yes"`
 }

 type ListLogLevelsOpts struct {
 	ListOutputOptions
 }

 type LogLevelOpts struct {
 	SetLogLevel   SetLogLevelOpts   `command:"set"`
 	GetLogLevels  GetLogLevelsOpts  `command:"get"`
 	ListLogLevels ListLogLevelsOpts `command:"list"`
 }

 var logLevelOpts = LogLevelOpts{}

 const (
 	DEFAULT_LOGLEVELS_FORMAT   = "table{{ .ComponentName }}\t{{.PackageName}}\t{{.Level}}"
 	DEFAULT_SETLOGLEVEL_FORMAT = "table{{ .ComponentName }}\t{{.Status}}\t{{.Error}}"
 )

 func RegisterLogLevelCommands(parent *flags.Parser) {
 	_, err := parent.AddCommand("loglevel", "loglevel commands", "Get and set log levels", &logLevelOpts)
 	if err != nil {
 		panic(err)
 	}
 }

 func MapListAppend(m map[string][]string, name string, item string) {
 	list, okay := m[name]
 	if okay {
 		m[name] = append(list, item)
 	} else {
 		m[name] = []string{item}
 	}
 }

 /*
  * A roundabout way of going of using the LogLevel enum to map from
  * a string to an integer that we can pass into the dynamic
  * proto.
  *
  * TODO: There's probably an easier way.
  */
 func LogLevelStringToInt(logLevelString string) (int32, error) {
 	ProcessGlobalOptions() // required for GetMethod()

 	/*
 	 * Use GetMethod() to get us a descriptor on the proto file we're
 	 * interested in.
 	 */

 	descriptor, _, err := GetMethod("update-log-level")
 	if err != nil {
 		return 0, err
 	}

 	/*
 	 * Map string LogLevel to enumerated type LogLevel
 	 * We have descriptor from above, which is a DescriptorSource
 	 * We can use FindSymbol to get at the message
 	 */

 	loggingSymbol, err := descriptor.FindSymbol("common.LogLevel")
 	if err != nil {
 		return 0, err
 	}

 	/*
 	 * LoggingSymbol is a Descriptor, but not a MessageDescrptior,
 	 * so we can't look at it's fields yet. Go back to the file,
 	 * call FindMessage to get the Message, then we can get the
 	 * embedded enum.
 	 */

 	loggingFile := loggingSymbol.GetFile()
 	logLevelMessage := loggingFile.FindMessage("common.LogLevel")
 	logLevelEnumType := logLevelMessage.GetNestedEnumTypes()[0]
 	enumLogLevel := logLevelEnumType.FindValueByName(logLevelString)

 	if enumLogLevel == nil {
 		return 0, fmt.Errorf("Unknown log level %s", logLevelString)
 	}

 	return enumLogLevel.GetNumber(), nil
 }

 // Validate a list of component names and throw an error if any one of them is bad.
 func ValidateComponentNames(kube_to_arouter map[string][]string, names []string) error {
 	var badNames []string
 	for _, name := range names {
 		_, ok := kube_to_arouter[name]
 		if !ok {
 			badNames = append(badNames, name)
 		}
 	}

 	if len(badNames) > 0 {
 		allowedNames := make([]string, len(kube_to_arouter))
 		i := 0
 		for k := range kube_to_arouter {
 			allowedNames[i] = k
 			i++
 		}

 		return fmt.Errorf("Unknown component(s): %s.\n  (Allowed values for component names: \n    %s)",
 			strings.Join(badNames, ", "),
 			strings.Join(allowedNames, ",\n    "))
 	} else {
 		return nil
 	}
 }

 func BuildKubernetesNameMap() (map[string][]string, map[string]string, error) {
 	kube_to_arouter := make(map[string][]string)
 	arouter_to_kube := make(map[string]string)

 	// use the current context in kubeconfig
 	config, err := clientcmd.BuildConfigFromFlags("", GlobalOptions.K8sConfig)
 	if err != nil {
 		return nil, nil, err
 	}

 	// create the clientset
 	clientset, err := kubernetes.NewForConfig(config)
 	if err != nil {
 		return nil, nil, err
 	}

 	pods, err := clientset.CoreV1().Pods("").List(metav1.ListOptions{
 		LabelSelector: "app.kubernetes.io/part-of=voltha",
 	})
 	if err != nil {
 		return nil, nil, err
 	}

 	if len(pods.Items) == 0 {
 		return nil, nil, fmt.Errorf("No Voltha pods found in Kubernetes -- verify pod is setup")
 	}

 	for _, pod := range pods.Items {
 		app, ok := pod.Labels["app"]
 		if !ok {
 			continue
 		}

 		var arouter_name string

 		switch app {
 		case "voltha-api-server":
 			/*
 			 * Assumes a single api_server for now.
 			 * TODO: Make labeling changes in charts to be able to derive name from labels
 			 */
 			arouter_name = "api_server0.api_server01"
 		case "rw-core":
 			affinity_group, ok := pod.Labels["affinity-group"]
 			if !ok {
 				Warn.Printf("rwcore %s lacks affinity-group label", pod.Name)
 				continue
 			}
 			affinity_group_core_id, ok := pod.Labels["affinity-group-core-id"]
 			if !ok {
 				Warn.Printf("rwcore %s lacks affinity-group-core-id label", pod.Name)
 				continue
 			}
 			arouter_name = "vcore" + affinity_group + ".vcore" + affinity_group + affinity_group_core_id
 		case "ro-core":
 			/*
 			 * Assumes a single rocore for now.
 			 * TODO: Make labeling changes in charts to be able to derive name from labels
 			 */
 			arouter_name = "ro_vcore0.ro_vcore01"
 		default:
 			// skip this pod as it's not relevant
 			continue
 		}

 		// Multiple ways to identify the component

 		// 1) The pod name. One pod name maps to exactly one pod.

 		arouter_to_kube[arouter_name] = pod.Name
 		MapListAppend(kube_to_arouter, pod.Name, arouter_name)

 		// 2) The kubernetes component name. A single component (i.e. "core") may map to multiple pods.

 		component, ok := pod.Labels["app.kubernetes.io/component"]
 		if ok {
 			MapListAppend(kube_to_arouter, component, arouter_name)
 		}

 		// 3) The voltha app label. A single app (i.e. "rwcore") may map to multiple pods.

 		MapListAppend(kube_to_arouter, app, arouter_name)

 	}

 	return kube_to_arouter, arouter_to_kube, nil
 }

 func (options *SetLogLevelOpts) Execute(args []string) error {
 	if len(options.Args.Component) == 0 {
 		return fmt.Errorf("Please specify at least one component")
 	}

 	kube_to_arouter, arouter_to_kube, err := BuildKubernetesNameMap()
 	if err != nil {
 		return err
 	}

 	var output []SetLogLevelOutput

 	// Validate component names, throw error now to avoid doing partial work
 	err = ValidateComponentNames(kube_to_arouter, options.Args.Component)
 	if err != nil {
 		return err
 	}

 	// Validate and map the logLevel string to an integer, throw error now to avoid doing partial work
 	intLogLevel, err := LogLevelStringToInt(options.Args.Level)
 	if err != nil {
 		return err
 	}

 	for _, kubeComponentName := range options.Args.Component {
 		var descriptor grpcurl.DescriptorSource
 		var conn *grpc.ClientConn
 		var method string

 		componentNameList := kube_to_arouter[kubeComponentName]

 		for _, componentName := range componentNameList {
 			conn, err = NewConnection()
 			if err != nil {
 				return err
 			}
 			defer conn.Close()
 			if strings.HasPrefix(componentName, "api_server") {
 				// apiserver's UpdateLogLevel is in the afrouter.Configuration gRPC package
 				descriptor, method, err = GetMethod("apiserver-update-log-level")
 			} else {
 				descriptor, method, err = GetMethod("update-log-level")
 			}
 			if err != nil {
 				return err
 			}

 			ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
 			defer cancel()

 			ll := make(map[string]interface{})
 			ll["component_name"] = componentName
 			ll["package_name"] = options.Package
 			ll["level"] = intLogLevel

 			h := &RpcEventHandler{
 				Fields: map[string]map[string]interface{}{"common.Logging": ll},
 			}
 			err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
 			if err != nil {
 				return err
 			}

 			if h.Status != nil && h.Status.Err() != nil {
 				output = append(output, SetLogLevelOutput{ComponentName: arouter_to_kube[componentName], Status: "Failure", Error: h.Status.Err().Error()})
 				continue
 			}

 			output = append(output, SetLogLevelOutput{ComponentName: arouter_to_kube[componentName], Status: "Success"})
 		}
 	}

 	outputFormat := CharReplacer.Replace(options.Format)
 	if outputFormat == "" {
 		outputFormat = GetCommandOptionWithDefault("loglevel-set", "format", DEFAULT_SETLOGLEVEL_FORMAT)
 	}

 	result := CommandResult{
 		Format:    format.Format(outputFormat),
 		OutputAs:  toOutputType(options.OutputAs),
 		NameLimit: options.NameLimit,
 		Data:      output,
 	}

 	GenerateOutput(&result)
 	return nil
 }

 func (options *GetLogLevelsOpts) getLogLevels(methodName string, args []string) error {
 	if len(options.Args.Component) == 0 {
 		return fmt.Errorf("Please specify at least one component")
 	}

 	kube_to_arouter, arouter_to_kube, err := BuildKubernetesNameMap()
 	if err != nil {
 		return err
 	}

 	var data []model.LogLevel

 	// Validate component names, throw error now to avoid doing partial work
 	err = ValidateComponentNames(kube_to_arouter, options.Args.Component)
 	if err != nil {
 		return err
 	}

 	for _, kubeComponentName := range options.Args.Component {
 		var descriptor grpcurl.DescriptorSource
 		var conn *grpc.ClientConn
 		var method string

 		componentNameList := kube_to_arouter[kubeComponentName]

 		for _, componentName := range componentNameList {
 			conn, err = NewConnection()
 			if err != nil {
 				return err
 			}
 			defer conn.Close()
 			if strings.HasPrefix(componentName, "api_server") {
 				// apiserver's UpdateLogLevel is in the afrouter.Configuration gRPC package
 				descriptor, method, err = GetMethod("apiserver-get-log-levels")
 			} else {
 				descriptor, method, err = GetMethod("get-log-levels")
 			}
 			if err != nil {
 				return err
 			}

 			ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
 			defer cancel()

 			ll := make(map[string]interface{})
 			ll["component_name"] = componentName

 			h := &RpcEventHandler{
 				Fields: map[string]map[string]interface{}{"common.LoggingComponent": ll},
 			}
 			err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
 			if err != nil {
 				return err
 			}

 			if h.Status != nil && h.Status.Err() != nil {
 				return h.Status.Err()
 			}

 			d, err := dynamic.AsDynamicMessage(h.Response)
 			if err != nil {
 				return err
 			}
 			items, err := d.TryGetFieldByName("items")
 			if err != nil {
 				return err
 			}

 			for _, item := range items.([]interface{}) {
 				logLevel := model.LogLevel{}
 				logLevel.PopulateFrom(item.(*dynamic.Message))
 				logLevel.ComponentName = arouter_to_kube[logLevel.ComponentName]

 				data = append(data, logLevel)
 			}
 		}
 	}

 	outputFormat := CharReplacer.Replace(options.Format)
 	if outputFormat == "" {
 		outputFormat = GetCommandOptionWithDefault(methodName, "format", DEFAULT_LOGLEVELS_FORMAT)
 	}
 	orderBy := options.OrderBy
 	if orderBy == "" {
 		orderBy = GetCommandOptionWithDefault(methodName, "order", "")
 	}

 	result := CommandResult{
 		Format:    format.Format(outputFormat),
 		Filter:    options.Filter,
 		OrderBy:   orderBy,
 		OutputAs:  toOutputType(options.OutputAs),
 		NameLimit: options.NameLimit,
 		Data:      data,
 	}
 	GenerateOutput(&result)
 	return nil
 }

 func (options *GetLogLevelsOpts) Execute(args []string) error {
 	return options.getLogLevels("loglevel-get", args)
 }

 func (options *ListLogLevelsOpts) Execute(args []string) error {
 	var getOptions GetLogLevelsOpts
 	var podNames []string

 	_, arouter_to_kube, err := BuildKubernetesNameMap()
 	if err != nil {
 		return err
 	}

 	for _, podName := range arouter_to_kube {
 		podNames = append(podNames, podName)
 	}

 	// Just call GetLogLevels with a list of podnames that includes everything relevant.

 	getOptions.ListOutputOptions = options.ListOutputOptions
 	getOptions.Args.Component = podNames

 	return getOptions.getLogLevels("loglevel-list", args)
 }
	/*
	* Copyright 2019-present Ciena Corporation
	*
	* 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 commands

	import (
	"context"
	"fmt"
	"github.com/fullstorydev/grpcurl"
	flags "github.com/jessevdk/go-flags"
	"github.com/jhump/protoreflect/dynamic"
	"github.com/opencord/voltctl/pkg/format"
	"github.com/opencord/voltctl/pkg/model"
	"google.golang.org/grpc"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/tools/clientcmd"
	"strings"
	)

	type SetLogLevelOutput struct {
	ComponentName string
	Status string
	Error string
	}

	type SetLogLevelOpts struct {
	OutputOptions
	Package string `short:"p" long:"package" description:"Package name to set log level"`
	Args struct {
	Level string
	Component []string
	} `positional-args:"yes" required:"yes"`
	}

	type GetLogLevelsOpts struct {
	ListOutputOptions
	Args struct {
	Component []string
	} `positional-args:"yes" required:"yes"`
	}

	type ListLogLevelsOpts struct {
	ListOutputOptions
	}

	type LogLevelOpts struct {
	SetLogLevel SetLogLevelOpts `command:"set"`
	GetLogLevels GetLogLevelsOpts `command:"get"`
	ListLogLevels ListLogLevelsOpts `command:"list"`
	}

	var logLevelOpts = LogLevelOpts{}

	const (
	DEFAULT_LOGLEVELS_FORMAT = "table{{ .ComponentName }}\t{{.PackageName}}\t{{.Level}}"
	DEFAULT_SETLOGLEVEL_FORMAT = "table{{ .ComponentName }}\t{{.Status}}\t{{.Error}}"
	)

	func RegisterLogLevelCommands(parent *flags.Parser) {
	_, err := parent.AddCommand("loglevel", "loglevel commands", "Get and set log levels", &logLevelOpts)
	if err != nil {
	panic(err)
	}
	}

	func MapListAppend(m map[string][]string, name string, item string) {
	list, okay := m[name]
	if okay {
	m[name] = append(list, item)
	} else {
	m[name] = []string{item}
	}
	}

	/*
	* A roundabout way of going of using the LogLevel enum to map from
	* a string to an integer that we can pass into the dynamic
	* proto.
	*
	* TODO: There's probably an easier way.
	*/
	func LogLevelStringToInt(logLevelString string) (int32, error) {
	ProcessGlobalOptions() // required for GetMethod()

	/*
	* Use GetMethod() to get us a descriptor on the proto file we're
	* interested in.
	*/

	descriptor, _, err := GetMethod("update-log-level")
	if err != nil {
	return 0, err
	}

	/*
	* Map string LogLevel to enumerated type LogLevel
	* We have descriptor from above, which is a DescriptorSource
	* We can use FindSymbol to get at the message
	*/

	loggingSymbol, err := descriptor.FindSymbol("common.LogLevel")
	if err != nil {
	return 0, err
	}

	/*
	* LoggingSymbol is a Descriptor, but not a MessageDescrptior,
	* so we can't look at it's fields yet. Go back to the file,
	* call FindMessage to get the Message, then we can get the
	* embedded enum.
	*/

	loggingFile := loggingSymbol.GetFile()
	logLevelMessage := loggingFile.FindMessage("common.LogLevel")
	logLevelEnumType := logLevelMessage.GetNestedEnumTypes()[0]
	enumLogLevel := logLevelEnumType.FindValueByName(logLevelString)

	if enumLogLevel == nil {
	return 0, fmt.Errorf("Unknown log level %s", logLevelString)
	}

	return enumLogLevel.GetNumber(), nil
	}

	// Validate a list of component names and throw an error if any one of them is bad.
	func ValidateComponentNames(kube_to_arouter map[string][]string, names []string) error {
	var badNames []string
	for _, name := range names {
	_, ok := kube_to_arouter[name]
	if !ok {
	badNames = append(badNames, name)
	}
	}

	if len(badNames) > 0 {
	allowedNames := make([]string, len(kube_to_arouter))
	i := 0
	for k := range kube_to_arouter {
	allowedNames[i] = k
	i++
	}

	return fmt.Errorf("Unknown component(s): %s.\n (Allowed values for component names: \n %s)",
	strings.Join(badNames, ", "),
	strings.Join(allowedNames, ",\n "))
	} else {
	return nil
	}
	}

	func BuildKubernetesNameMap() (map[string][]string, map[string]string, error) {
	kube_to_arouter := make(map[string][]string)
	arouter_to_kube := make(map[string]string)

	// use the current context in kubeconfig
	config, err := clientcmd.BuildConfigFromFlags("", GlobalOptions.K8sConfig)
	if err != nil {
	return nil, nil, err
	}

	// create the clientset
	clientset, err := kubernetes.NewForConfig(config)
	if err != nil {
	return nil, nil, err
	}

	pods, err := clientset.CoreV1().Pods("").List(metav1.ListOptions{
	LabelSelector: "app.kubernetes.io/part-of=voltha",
	})
	if err != nil {
	return nil, nil, err
	}

	if len(pods.Items) == 0 {
	return nil, nil, fmt.Errorf("No Voltha pods found in Kubernetes -- verify pod is setup")
	}

	for _, pod := range pods.Items {
	app, ok := pod.Labels["app"]
	if !ok {
	continue
	}

	var arouter_name string

	switch app {
	case "voltha-api-server":
	/*
	* Assumes a single api_server for now.
	* TODO: Make labeling changes in charts to be able to derive name from labels
	*/
	arouter_name = "api_server0.api_server01"
	case "rw-core":
	affinity_group, ok := pod.Labels["affinity-group"]
	if !ok {
	Warn.Printf("rwcore %s lacks affinity-group label", pod.Name)
	continue
	}
	affinity_group_core_id, ok := pod.Labels["affinity-group-core-id"]
	if !ok {
	Warn.Printf("rwcore %s lacks affinity-group-core-id label", pod.Name)
	continue
	}
	arouter_name = "vcore" + affinity_group + ".vcore" + affinity_group + affinity_group_core_id
	case "ro-core":
	/*
	* Assumes a single rocore for now.
	* TODO: Make labeling changes in charts to be able to derive name from labels
	*/
	arouter_name = "ro_vcore0.ro_vcore01"
	default:
	// skip this pod as it's not relevant
	continue
	}

	// Multiple ways to identify the component

	// 1) The pod name. One pod name maps to exactly one pod.

	arouter_to_kube[arouter_name] = pod.Name
	MapListAppend(kube_to_arouter, pod.Name, arouter_name)

	// 2) The kubernetes component name. A single component (i.e. "core") may map to multiple pods.

	component, ok := pod.Labels["app.kubernetes.io/component"]
	if ok {
	MapListAppend(kube_to_arouter, component, arouter_name)
	}

	// 3) The voltha app label. A single app (i.e. "rwcore") may map to multiple pods.

	MapListAppend(kube_to_arouter, app, arouter_name)

	}

	return kube_to_arouter, arouter_to_kube, nil
	}

	func (options *SetLogLevelOpts) Execute(args []string) error {
	if len(options.Args.Component) == 0 {
	return fmt.Errorf("Please specify at least one component")
	}

	kube_to_arouter, arouter_to_kube, err := BuildKubernetesNameMap()
	if err != nil {
	return err
	}

	var output []SetLogLevelOutput

	// Validate component names, throw error now to avoid doing partial work
	err = ValidateComponentNames(kube_to_arouter, options.Args.Component)
	if err != nil {
	return err
	}

	// Validate and map the logLevel string to an integer, throw error now to avoid doing partial work
	intLogLevel, err := LogLevelStringToInt(options.Args.Level)
	if err != nil {
	return err
	}

	for _, kubeComponentName := range options.Args.Component {
	var descriptor grpcurl.DescriptorSource
	var conn *grpc.ClientConn
	var method string

	componentNameList := kube_to_arouter[kubeComponentName]

	for _, componentName := range componentNameList {
	conn, err = NewConnection()
	if err != nil {
	return err
	}
	defer conn.Close()
	if strings.HasPrefix(componentName, "api_server") {
	// apiserver's UpdateLogLevel is in the afrouter.Configuration gRPC package
	descriptor, method, err = GetMethod("apiserver-update-log-level")
	} else {
	descriptor, method, err = GetMethod("update-log-level")
	}
	if err != nil {
	return err
	}

	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
	defer cancel()

	ll := make(map[string]interface{})
	ll["component_name"] = componentName
	ll["package_name"] = options.Package
	ll["level"] = intLogLevel

	h := &RpcEventHandler{
	Fields: map[string]map[string]interface{}{"common.Logging": ll},
	}
	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
	if err != nil {
	return err
	}

	if h.Status != nil && h.Status.Err() != nil {
	output = append(output, SetLogLevelOutput{ComponentName: arouter_to_kube[componentName], Status: "Failure", Error: h.Status.Err().Error()})
	continue
	}

	output = append(output, SetLogLevelOutput{ComponentName: arouter_to_kube[componentName], Status: "Success"})
	}
	}

	outputFormat := CharReplacer.Replace(options.Format)
	if outputFormat == "" {
	outputFormat = GetCommandOptionWithDefault("loglevel-set", "format", DEFAULT_SETLOGLEVEL_FORMAT)
	}

	result := CommandResult{
	Format: format.Format(outputFormat),
	OutputAs: toOutputType(options.OutputAs),
	NameLimit: options.NameLimit,
	Data: output,
	}

	GenerateOutput(&result)
	return nil
	}

	func (options *GetLogLevelsOpts) getLogLevels(methodName string, args []string) error {
	if len(options.Args.Component) == 0 {
	return fmt.Errorf("Please specify at least one component")
	}

	kube_to_arouter, arouter_to_kube, err := BuildKubernetesNameMap()
	if err != nil {
	return err
	}

	var data []model.LogLevel

	// Validate component names, throw error now to avoid doing partial work
	err = ValidateComponentNames(kube_to_arouter, options.Args.Component)
	if err != nil {
	return err
	}

	for _, kubeComponentName := range options.Args.Component {
	var descriptor grpcurl.DescriptorSource
	var conn *grpc.ClientConn
	var method string

	componentNameList := kube_to_arouter[kubeComponentName]

	for _, componentName := range componentNameList {
	conn, err = NewConnection()
	if err != nil {
	return err
	}
	defer conn.Close()
	if strings.HasPrefix(componentName, "api_server") {
	// apiserver's UpdateLogLevel is in the afrouter.Configuration gRPC package
	descriptor, method, err = GetMethod("apiserver-get-log-levels")
	} else {
	descriptor, method, err = GetMethod("get-log-levels")
	}
	if err != nil {
	return err
	}

	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
	defer cancel()

	ll := make(map[string]interface{})
	ll["component_name"] = componentName

	h := &RpcEventHandler{
	Fields: map[string]map[string]interface{}{"common.LoggingComponent": ll},
	}
	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
	if err != nil {
	return err
	}

	if h.Status != nil && h.Status.Err() != nil {
	return h.Status.Err()
	}

	d, err := dynamic.AsDynamicMessage(h.Response)
	if err != nil {
	return err
	}
	items, err := d.TryGetFieldByName("items")
	if err != nil {
	return err
	}

	for _, item := range items.([]interface{}) {
	logLevel := model.LogLevel{}
	logLevel.PopulateFrom(item.(*dynamic.Message))
	logLevel.ComponentName = arouter_to_kube[logLevel.ComponentName]

	data = append(data, logLevel)
	}
	}
	}

	outputFormat := CharReplacer.Replace(options.Format)
	if outputFormat == "" {
	outputFormat = GetCommandOptionWithDefault(methodName, "format", DEFAULT_LOGLEVELS_FORMAT)
	}
	orderBy := options.OrderBy
	if orderBy == "" {
	orderBy = GetCommandOptionWithDefault(methodName, "order", "")
	}

	result := CommandResult{
	Format: format.Format(outputFormat),
	Filter: options.Filter,
	OrderBy: orderBy,
	OutputAs: toOutputType(options.OutputAs),
	NameLimit: options.NameLimit,
	Data: data,
	}
	GenerateOutput(&result)
	return nil
	}

	func (options *GetLogLevelsOpts) Execute(args []string) error {
	return options.getLogLevels("loglevel-get", args)
	}

	func (options *ListLogLevelsOpts) Execute(args []string) error {
	var getOptions GetLogLevelsOpts
	var podNames []string

	_, arouter_to_kube, err := BuildKubernetesNameMap()
	if err != nil {
	return err
	}

	for _, podName := range arouter_to_kube {
	podNames = append(podNames, podName)
	}

	// Just call GetLogLevels with a list of podnames that includes everything relevant.

	getOptions.ListOutputOptions = options.ListOutputOptions
	getOptions.Args.Component = podNames

	return getOptions.getLogLevels("loglevel-list", args)
	}