pkg/config/logcontroller.go - voltha-lib-go - Gitiles

 /*
  * Copyright 2018-present Open Networking Foundation

  * 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 Config provides dynamic logging configuration for specific Voltha component with loglevel lookup
 // from etcd kvstore implemented using Backend.
 // Any Voltha component can start utilizing dynamic logging by starting goroutine of StartLogLevelConfigProcessing after
 // starting kvClient for the component.

 package config

 import (
 	"context"
 	"crypto/md5"
 	"encoding/json"
 	"errors"
 	"os"
 	"sort"
 	"strings"

 	"github.com/opencord/voltha-lib-go/v7/pkg/log"
 )

 const (
 	defaultLogLevelKey                = "default"          // kvstore key containing default loglevel
 	globalConfigRootNode              = "global"           // Root Node in kvstore containing global config
 	initialGlobalDefaultLogLevelValue = "WARN"             // Hard-coded Global Default loglevel pushed at PoD startup
 	logPackagesListKey                = "log_package_list" // kvstore key containing list of allowed log packages
 )

 // ComponentLogController represents a Configuration for Logging Config of specific Voltha component type
 // It stores ComponentConfig and GlobalConfig of loglevel config of specific Voltha component type
 // For example,ComponentLogController instance will be created for rw-core component
 type ComponentLogController struct {
 	ComponentName       string
 	componentNameConfig *ComponentConfig
 	GlobalConfig        *ComponentConfig
 	configManager       *ConfigManager
 	logHash             [16]byte
 	initialLogLevel     string // Initial default log level set by helm chart
 }

 func NewComponentLogController(ctx context.Context, cm *ConfigManager) (*ComponentLogController, error) {
 	logger.Debug(ctx, "creating-new-component-log-controller")
 	componentName := os.Getenv("COMPONENT_NAME")
 	if componentName == "" {
 		return nil, errors.New("Unable to retrieve PoD Component Name from Runtime env")
 	}

 	var defaultLogLevel string
 	var err error
 	// Retrieve and save default log level; used for fallback if all loglevel config is cleared in etcd
 	if defaultLogLevel, err = log.LogLevelToString(log.GetDefaultLogLevel()); err != nil {
 		defaultLogLevel = "DEBUG"
 	}

 	return &ComponentLogController{
 		ComponentName:       componentName,
 		componentNameConfig: nil,
 		GlobalConfig:        nil,
 		configManager:       cm,
 		initialLogLevel:     defaultLogLevel,
 	}, nil

 }

 // StartLogLevelConfigProcessing initialize component config and global config
 // Then, it persists initial default Loglevels into Config Store before
 // starting the loading and processing of all Log Configuration
 func StartLogLevelConfigProcessing(cm *ConfigManager, ctx context.Context) {
 	cc, err := NewComponentLogController(ctx, cm)
 	if err != nil {
 		logger.Errorw(ctx, "unable-to-construct-component-log-controller-instance-for-log-config-monitoring", log.Fields{"error": err})
 		return
 	}

 	cc.GlobalConfig = cm.InitComponentConfig(globalConfigRootNode, ConfigTypeLogLevel)
 	logger.Debugw(ctx, "global-log-config", log.Fields{"cc-global-config": cc.GlobalConfig})

 	cc.componentNameConfig = cm.InitComponentConfig(cc.ComponentName, ConfigTypeLogLevel)
 	logger.Debugw(ctx, "component-log-config", log.Fields{"cc-component-name-config": cc.componentNameConfig})

 	cc.persistInitialDefaultLogConfigs(ctx)

 	cc.persistRegisteredLogPackageList(ctx)

 	cc.processLogConfig(ctx)
 }

 // Method to persist Global default loglevel into etcd, if not set yet
 // It also checks and set Component default loglevel into etcd with initial loglevel set from command line
 func (c *ComponentLogController) persistInitialDefaultLogConfigs(ctx context.Context) {

 	_, err := c.GlobalConfig.Retrieve(ctx, defaultLogLevelKey)
 	if err != nil {
 		logger.Debugw(ctx, "failed-to-retrieve-global-default-log-config-at-startup", log.Fields{"error": err})

 		err = c.GlobalConfig.Save(ctx, defaultLogLevelKey, initialGlobalDefaultLogLevelValue)
 		if err != nil {
 			logger.Errorw(ctx, "failed-to-persist-global-default-log-config-at-startup", log.Fields{"error": err, "loglevel": initialGlobalDefaultLogLevelValue})
 		}
 	}

 	_, err = c.componentNameConfig.Retrieve(ctx, defaultLogLevelKey)
 	if err != nil {
 		logger.Debugw(ctx, "failed-to-retrieve-component-default-log-config-at-startup", log.Fields{"error": err})

 		err = c.componentNameConfig.Save(ctx, defaultLogLevelKey, c.initialLogLevel)
 		if err != nil {
 			logger.Errorw(ctx, "failed-to-persist-component-default-log-config-at-startup", log.Fields{"error": err, "loglevel": c.initialLogLevel})
 		}
 	}
 }

 // Method to save list of all registered packages for component into config kvstore. A single string
 // is constructed with comma-separated package names in sorted order and persisted
 func (c *ComponentLogController) persistRegisteredLogPackageList(ctx context.Context) {

 	componentMetadataConfig := c.configManager.InitComponentConfig(c.ComponentName, ConfigTypeMetadata)
 	logger.Debugw(ctx, "component-metadata-config", log.Fields{"component-metadata-config": componentMetadataConfig})

 	packageList := log.GetPackageNames()
 	packageList = append(packageList, defaultLogLevelKey)
 	sort.Strings(packageList)

 	packageNames, err := json.Marshal(packageList)
 	if err != nil {
 		logger.Errorw(ctx, "failed-to-marshal-log-package-list-for-storage", log.Fields{"error": err, "packageList": packageList})
 		return
 	}

 	if err := componentMetadataConfig.Save(ctx, logPackagesListKey, string(packageNames)); err != nil {
 		logger.Errorw(ctx, "failed-to-persist-component-registered-log-package-list-at-startup", log.Fields{"error": err, "packageNames": packageNames})
 	}
 }

 // ProcessLogConfig will first load and apply log config and then start waiting on component config and global config
 // channels for any changes. Event channel will be recieved from Backend for valid change type
 // Then data for componentn log config and global log config will be retrieved from Backend and stored in updatedLogConfig in precedence order
 // If any changes in updatedLogConfig will be applied on component
 func (c *ComponentLogController) processLogConfig(ctx context.Context) {

 	// Load and apply Log Config for first time
 	initialLogConfig, err := c.buildUpdatedLogConfig(ctx)
 	if err != nil {
 		logger.Warnw(ctx, "unable-to-load-log-config-at-startup", log.Fields{"error": err})
 	} else {
 		if err := c.loadAndApplyLogConfig(ctx, initialLogConfig); err != nil {
 			logger.Warnw(ctx, "unable-to-apply-log-config-at-startup", log.Fields{"error": err})
 		}
 	}

 	componentConfigEventChan := c.componentNameConfig.MonitorForConfigChange(ctx)

 	globalConfigEventChan := c.GlobalConfig.MonitorForConfigChange(ctx)

 	// process the events for componentName and  global config
 	var configEvent *ConfigChangeEvent
 	for {
 		select {
 		case configEvent = <-globalConfigEventChan:
 		case configEvent = <-componentConfigEventChan:

 		}
 		logger.Debugw(ctx, "processing-log-config-change", log.Fields{"ChangeType": configEvent.ChangeType, "Package": configEvent.ConfigAttribute})

 		updatedLogConfig, err := c.buildUpdatedLogConfig(ctx)
 		if err != nil {
 			logger.Warnw(ctx, "unable-to-fetch-updated-log-config", log.Fields{"error": err})
 			continue
 		}

 		logger.Debugw(ctx, "applying-updated-log-config", log.Fields{"updated-log-config": updatedLogConfig})

 		if err := c.loadAndApplyLogConfig(ctx, updatedLogConfig); err != nil {
 			logger.Warnw(ctx, "unable-to-load-and-apply-log-config", log.Fields{"error": err})
 		}
 	}

 }

 // get active loglevel from the zap logger
 func getActiveLogLevels(ctx context.Context) map[string]string {
 	loglevels := make(map[string]string)

 	// now do the default log level
 	if level, err := log.LogLevelToString(log.GetDefaultLogLevel()); err == nil {
 		loglevels[defaultLogLevelKey] = level
 	}

 	// do the per-package log levels
 	for _, packageName := range log.GetPackageNames() {
 		level, err := log.GetPackageLogLevel(packageName)
 		if err != nil {
 			logger.Warnw(ctx, "unable-to-fetch-current-active-loglevel-for-package-name", log.Fields{"package-name": packageName, "error": err})
 			continue
 		}

 		if l, err := log.LogLevelToString(level); err == nil {
 			loglevels[packageName] = l
 		}
 	}

 	logger.Debugw(ctx, "retreived-log-levels-from-zap-logger", log.Fields{"loglevels": loglevels})

 	return loglevels
 }

 func (c *ComponentLogController) getGlobalLogConfig(ctx context.Context) (string, error) {

 	globalDefaultLogLevel, err := c.GlobalConfig.Retrieve(ctx, defaultLogLevelKey)
 	if err != nil {
 		return "", err
 	}

 	// Handle edge cases when global default loglevel is deleted directly from etcd or set to a invalid value
 	// We should use hard-coded initial default value in such cases
 	if globalDefaultLogLevel == "" {
 		logger.Warn(ctx, "global-default-loglevel-not-found-in-config-store")
 		globalDefaultLogLevel = initialGlobalDefaultLogLevelValue
 	}

 	if _, err := log.StringToLogLevel(globalDefaultLogLevel); err != nil {
 		logger.Warnw(ctx, "unsupported-loglevel-config-defined-at-global-default", log.Fields{"log-level": globalDefaultLogLevel})
 		globalDefaultLogLevel = initialGlobalDefaultLogLevelValue
 	}

 	logger.Debugw(ctx, "retrieved-global-default-loglevel", log.Fields{"level": globalDefaultLogLevel})

 	return globalDefaultLogLevel, nil
 }

 func (c *ComponentLogController) getComponentLogConfig(ctx context.Context, globalDefaultLogLevel string) (map[string]string, error) {
 	componentLogConfig, err := c.componentNameConfig.RetrieveAll(ctx)
 	if err != nil {
 		return nil, err
 	}

 	effectiveDefaultLogLevel := ""
 	for logConfigKey, logConfigValue := range componentLogConfig {
 		if _, err := log.StringToLogLevel(logConfigValue); err != nil || logConfigKey == "" {
 			logger.Warnw(ctx, "unsupported-loglevel-config-defined-at-component-context", log.Fields{"package-name": logConfigKey, "log-level": logConfigValue})
 			delete(componentLogConfig, logConfigKey)
 		} else {
 			if logConfigKey == defaultLogLevelKey {
 				effectiveDefaultLogLevel = componentLogConfig[defaultLogLevelKey]
 			}
 		}
 	}

 	// if default loglevel is not configured for the component, component should use
 	// default loglevel configured at global level
 	if effectiveDefaultLogLevel == "" {
 		effectiveDefaultLogLevel = globalDefaultLogLevel
 	}

 	componentLogConfig[defaultLogLevelKey] = effectiveDefaultLogLevel

 	logger.Debugw(ctx, "retrieved-component-log-config", log.Fields{"component-log-level": componentLogConfig})

 	return componentLogConfig, nil
 }

 // buildUpdatedLogConfig retrieve the global logConfig and component logConfig  from Backend
 // component logConfig stores the log config with precedence order
 // For example, If the global logConfig is set and component logConfig is set only for specific package then
 // component logConfig is stored with global logConfig  and component logConfig of specific package
 // For example, If the global logConfig is set and component logConfig is set for specific package and as well as for default then
 // component logConfig is stored with  component logConfig data only
 func (c *ComponentLogController) buildUpdatedLogConfig(ctx context.Context) (map[string]string, error) {
 	globalLogLevel, err := c.getGlobalLogConfig(ctx)
 	if err != nil {
 		logger.Errorw(ctx, "unable-to-retrieve-global-log-config", log.Fields{"err": err})
 	}

 	componentLogConfig, err := c.getComponentLogConfig(ctx, globalLogLevel)
 	if err != nil {
 		return nil, err
 	}

 	finalLogConfig := make(map[string]string)
 	for packageName, logLevel := range componentLogConfig {
 		finalLogConfig[strings.ReplaceAll(packageName, "#", "/")] = logLevel
 	}

 	return finalLogConfig, nil
 }

 // load and apply the current configuration for component name
 // create hash of loaded configuration using GenerateLogConfigHash
 // if there is previous hash stored, compare the hash to stored hash
 // if there is any change will call UpdateLogLevels
 func (c *ComponentLogController) loadAndApplyLogConfig(ctx context.Context, logConfig map[string]string) error {
 	currentLogHash, err := GenerateLogConfigHash(logConfig)
 	if err != nil {
 		return err
 	}

 	if c.logHash != currentLogHash {
 		updateLogLevels(ctx, logConfig)
 		c.logHash = currentLogHash
 	} else {
 		logger.Debug(ctx, "effective-loglevel-config-same-as-currently-active")
 	}

 	return nil
 }

 // createModifiedLogLevels loops through the activeLogLevels recieved from zap logger and updatedLogLevels recieved from buildUpdatedLogConfig
 // to identify and create map of modified Log Levels of 2 types:
 // - Packages for which log level has been changed
 // - Packages for which log level config has been cleared - set to default log level
 func createModifiedLogLevels(ctx context.Context, activeLogLevels, updatedLogLevels map[string]string) map[string]string {
 	defaultLevel := updatedLogLevels[defaultLogLevelKey]

 	modifiedLogLevels := make(map[string]string)
 	for activeKey, activeLevel := range activeLogLevels {
 		if _, exist := updatedLogLevels[activeKey]; !exist {
 			if activeLevel != defaultLevel {
 				modifiedLogLevels[activeKey] = defaultLevel
 			}
 		} else if activeLevel != updatedLogLevels[activeKey] {
 			modifiedLogLevels[activeKey] = updatedLogLevels[activeKey]
 		}
 	}

 	// Log warnings for all invalid packages for which log config has been set
 	for key, value := range updatedLogLevels {
 		if _, exist := activeLogLevels[key]; !exist {
 			logger.Warnw(ctx, "ignoring-loglevel-set-for-invalid-package", log.Fields{"package": key, "log-level": value})
 		}
 	}

 	return modifiedLogLevels
 }

 // updateLogLevels update the loglevels for the component
 // retrieve active confguration from logger
 // compare with entries one by one and apply
 func updateLogLevels(ctx context.Context, updatedLogConfig map[string]string) {

 	activeLogLevels := getActiveLogLevels(ctx)
 	changedLogLevels := createModifiedLogLevels(ctx, activeLogLevels, updatedLogConfig)

 	// If no changed log levels are found, just return. It may happen on configuration of a invalid package
 	if len(changedLogLevels) == 0 {
 		logger.Debug(ctx, "no-change-in-effective-loglevel-config")
 		return
 	}

 	logger.Debugw(ctx, "applying-log-level-for-modified-packages", log.Fields{"changed-log-levels": changedLogLevels})
 	for key, level := range changedLogLevels {
 		if key == defaultLogLevelKey {
 			if l, err := log.StringToLogLevel(level); err == nil {
 				log.SetDefaultLogLevel(l)
 			}
 		} else {
 			if l, err := log.StringToLogLevel(level); err == nil {
 				log.SetPackageLogLevel(key, l)
 			}
 		}
 	}
 }

 // generate md5 hash of key value pairs appended into a single string
 // in order by key name
 func GenerateLogConfigHash(createHashLog map[string]string) ([16]byte, error) {
 	createHashLogBytes := []byte{}
 	levelData, err := json.Marshal(createHashLog)
 	if err != nil {
 		return [16]byte{}, err
 	}
 	createHashLogBytes = append(createHashLogBytes, levelData...)
 	return md5.Sum(createHashLogBytes), nil
 }
	/*
	* Copyright 2018-present Open Networking Foundation

	* 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 Config provides dynamic logging configuration for specific Voltha component with loglevel lookup
	// from etcd kvstore implemented using Backend.
	// Any Voltha component can start utilizing dynamic logging by starting goroutine of StartLogLevelConfigProcessing after
	// starting kvClient for the component.

	package config

	import (
	"context"
	"crypto/md5"
	"encoding/json"
	"errors"
	"os"
	"sort"
	"strings"

	"github.com/opencord/voltha-lib-go/v7/pkg/log"
	)

	const (
	defaultLogLevelKey = "default" // kvstore key containing default loglevel
	globalConfigRootNode = "global" // Root Node in kvstore containing global config
	initialGlobalDefaultLogLevelValue = "WARN" // Hard-coded Global Default loglevel pushed at PoD startup
	logPackagesListKey = "log_package_list" // kvstore key containing list of allowed log packages
	)

	// ComponentLogController represents a Configuration for Logging Config of specific Voltha component type
	// It stores ComponentConfig and GlobalConfig of loglevel config of specific Voltha component type
	// For example,ComponentLogController instance will be created for rw-core component
	type ComponentLogController struct {
	ComponentName string
	componentNameConfig *ComponentConfig
	GlobalConfig *ComponentConfig
	configManager *ConfigManager
	logHash [16]byte
	initialLogLevel string // Initial default log level set by helm chart
	}

	func NewComponentLogController(ctx context.Context, cm ConfigManager) (ComponentLogController, error) {
	logger.Debug(ctx, "creating-new-component-log-controller")
	componentName := os.Getenv("COMPONENT_NAME")
	if componentName == "" {
	return nil, errors.New("Unable to retrieve PoD Component Name from Runtime env")
	}

	var defaultLogLevel string
	var err error
	// Retrieve and save default log level; used for fallback if all loglevel config is cleared in etcd
	if defaultLogLevel, err = log.LogLevelToString(log.GetDefaultLogLevel()); err != nil {
	defaultLogLevel = "DEBUG"
	}

	return &ComponentLogController{
	ComponentName: componentName,
	componentNameConfig: nil,
	GlobalConfig: nil,
	configManager: cm,
	initialLogLevel: defaultLogLevel,
	}, nil

	}

	// StartLogLevelConfigProcessing initialize component config and global config
	// Then, it persists initial default Loglevels into Config Store before
	// starting the loading and processing of all Log Configuration
	func StartLogLevelConfigProcessing(cm *ConfigManager, ctx context.Context) {
	cc, err := NewComponentLogController(ctx, cm)
	if err != nil {
	logger.Errorw(ctx, "unable-to-construct-component-log-controller-instance-for-log-config-monitoring", log.Fields{"error": err})
	return
	}

	cc.GlobalConfig = cm.InitComponentConfig(globalConfigRootNode, ConfigTypeLogLevel)
	logger.Debugw(ctx, "global-log-config", log.Fields{"cc-global-config": cc.GlobalConfig})

	cc.componentNameConfig = cm.InitComponentConfig(cc.ComponentName, ConfigTypeLogLevel)
	logger.Debugw(ctx, "component-log-config", log.Fields{"cc-component-name-config": cc.componentNameConfig})

	cc.persistInitialDefaultLogConfigs(ctx)

	cc.persistRegisteredLogPackageList(ctx)

	cc.processLogConfig(ctx)
	}

	// Method to persist Global default loglevel into etcd, if not set yet
	// It also checks and set Component default loglevel into etcd with initial loglevel set from command line
	func (c *ComponentLogController) persistInitialDefaultLogConfigs(ctx context.Context) {

	_, err := c.GlobalConfig.Retrieve(ctx, defaultLogLevelKey)
	if err != nil {
	logger.Debugw(ctx, "failed-to-retrieve-global-default-log-config-at-startup", log.Fields{"error": err})

	err = c.GlobalConfig.Save(ctx, defaultLogLevelKey, initialGlobalDefaultLogLevelValue)
	if err != nil {
	logger.Errorw(ctx, "failed-to-persist-global-default-log-config-at-startup", log.Fields{"error": err, "loglevel": initialGlobalDefaultLogLevelValue})
	}
	}

	_, err = c.componentNameConfig.Retrieve(ctx, defaultLogLevelKey)
	if err != nil {
	logger.Debugw(ctx, "failed-to-retrieve-component-default-log-config-at-startup", log.Fields{"error": err})

	err = c.componentNameConfig.Save(ctx, defaultLogLevelKey, c.initialLogLevel)
	if err != nil {
	logger.Errorw(ctx, "failed-to-persist-component-default-log-config-at-startup", log.Fields{"error": err, "loglevel": c.initialLogLevel})
	}
	}
	}

	// Method to save list of all registered packages for component into config kvstore. A single string
	// is constructed with comma-separated package names in sorted order and persisted
	func (c *ComponentLogController) persistRegisteredLogPackageList(ctx context.Context) {

	componentMetadataConfig := c.configManager.InitComponentConfig(c.ComponentName, ConfigTypeMetadata)
	logger.Debugw(ctx, "component-metadata-config", log.Fields{"component-metadata-config": componentMetadataConfig})

	packageList := log.GetPackageNames()
	packageList = append(packageList, defaultLogLevelKey)
	sort.Strings(packageList)

	packageNames, err := json.Marshal(packageList)
	if err != nil {
	logger.Errorw(ctx, "failed-to-marshal-log-package-list-for-storage", log.Fields{"error": err, "packageList": packageList})
	return
	}

	if err := componentMetadataConfig.Save(ctx, logPackagesListKey, string(packageNames)); err != nil {
	logger.Errorw(ctx, "failed-to-persist-component-registered-log-package-list-at-startup", log.Fields{"error": err, "packageNames": packageNames})
	}
	}

	// ProcessLogConfig will first load and apply log config and then start waiting on component config and global config
	// channels for any changes. Event channel will be recieved from Backend for valid change type
	// Then data for componentn log config and global log config will be retrieved from Backend and stored in updatedLogConfig in precedence order
	// If any changes in updatedLogConfig will be applied on component
	func (c *ComponentLogController) processLogConfig(ctx context.Context) {

	// Load and apply Log Config for first time
	initialLogConfig, err := c.buildUpdatedLogConfig(ctx)
	if err != nil {
	logger.Warnw(ctx, "unable-to-load-log-config-at-startup", log.Fields{"error": err})
	} else {
	if err := c.loadAndApplyLogConfig(ctx, initialLogConfig); err != nil {
	logger.Warnw(ctx, "unable-to-apply-log-config-at-startup", log.Fields{"error": err})
	}
	}

	componentConfigEventChan := c.componentNameConfig.MonitorForConfigChange(ctx)

	globalConfigEventChan := c.GlobalConfig.MonitorForConfigChange(ctx)

	// process the events for componentName and global config
	var configEvent *ConfigChangeEvent
	for {
	select {
	case configEvent = <-globalConfigEventChan:
	case configEvent = <-componentConfigEventChan:

	}
	logger.Debugw(ctx, "processing-log-config-change", log.Fields{"ChangeType": configEvent.ChangeType, "Package": configEvent.ConfigAttribute})

	updatedLogConfig, err := c.buildUpdatedLogConfig(ctx)
	if err != nil {
	logger.Warnw(ctx, "unable-to-fetch-updated-log-config", log.Fields{"error": err})
	continue
	}

	logger.Debugw(ctx, "applying-updated-log-config", log.Fields{"updated-log-config": updatedLogConfig})

	if err := c.loadAndApplyLogConfig(ctx, updatedLogConfig); err != nil {
	logger.Warnw(ctx, "unable-to-load-and-apply-log-config", log.Fields{"error": err})
	}
	}

	}

	// get active loglevel from the zap logger
	func getActiveLogLevels(ctx context.Context) map[string]string {
	loglevels := make(map[string]string)

	// now do the default log level
	if level, err := log.LogLevelToString(log.GetDefaultLogLevel()); err == nil {
	loglevels[defaultLogLevelKey] = level
	}

	// do the per-package log levels
	for _, packageName := range log.GetPackageNames() {
	level, err := log.GetPackageLogLevel(packageName)
	if err != nil {
	logger.Warnw(ctx, "unable-to-fetch-current-active-loglevel-for-package-name", log.Fields{"package-name": packageName, "error": err})
	continue
	}

	if l, err := log.LogLevelToString(level); err == nil {
	loglevels[packageName] = l
	}
	}

	logger.Debugw(ctx, "retreived-log-levels-from-zap-logger", log.Fields{"loglevels": loglevels})

	return loglevels
	}

	func (c *ComponentLogController) getGlobalLogConfig(ctx context.Context) (string, error) {

	globalDefaultLogLevel, err := c.GlobalConfig.Retrieve(ctx, defaultLogLevelKey)
	if err != nil {
	return "", err
	}

	// Handle edge cases when global default loglevel is deleted directly from etcd or set to a invalid value
	// We should use hard-coded initial default value in such cases
	if globalDefaultLogLevel == "" {
	logger.Warn(ctx, "global-default-loglevel-not-found-in-config-store")
	globalDefaultLogLevel = initialGlobalDefaultLogLevelValue
	}

	if _, err := log.StringToLogLevel(globalDefaultLogLevel); err != nil {
	logger.Warnw(ctx, "unsupported-loglevel-config-defined-at-global-default", log.Fields{"log-level": globalDefaultLogLevel})
	globalDefaultLogLevel = initialGlobalDefaultLogLevelValue
	}

	logger.Debugw(ctx, "retrieved-global-default-loglevel", log.Fields{"level": globalDefaultLogLevel})

	return globalDefaultLogLevel, nil
	}

	func (c *ComponentLogController) getComponentLogConfig(ctx context.Context, globalDefaultLogLevel string) (map[string]string, error) {
	componentLogConfig, err := c.componentNameConfig.RetrieveAll(ctx)
	if err != nil {
	return nil, err
	}

	effectiveDefaultLogLevel := ""
	for logConfigKey, logConfigValue := range componentLogConfig {
	if _, err := log.StringToLogLevel(logConfigValue); err != nil \|\| logConfigKey == "" {
	logger.Warnw(ctx, "unsupported-loglevel-config-defined-at-component-context", log.Fields{"package-name": logConfigKey, "log-level": logConfigValue})
	delete(componentLogConfig, logConfigKey)
	} else {
	if logConfigKey == defaultLogLevelKey {
	effectiveDefaultLogLevel = componentLogConfig[defaultLogLevelKey]
	}
	}
	}

	// if default loglevel is not configured for the component, component should use
	// default loglevel configured at global level
	if effectiveDefaultLogLevel == "" {
	effectiveDefaultLogLevel = globalDefaultLogLevel
	}

	componentLogConfig[defaultLogLevelKey] = effectiveDefaultLogLevel

	logger.Debugw(ctx, "retrieved-component-log-config", log.Fields{"component-log-level": componentLogConfig})

	return componentLogConfig, nil
	}

	// buildUpdatedLogConfig retrieve the global logConfig and component logConfig from Backend
	// component logConfig stores the log config with precedence order
	// For example, If the global logConfig is set and component logConfig is set only for specific package then
	// component logConfig is stored with global logConfig and component logConfig of specific package
	// For example, If the global logConfig is set and component logConfig is set for specific package and as well as for default then
	// component logConfig is stored with component logConfig data only
	func (c *ComponentLogController) buildUpdatedLogConfig(ctx context.Context) (map[string]string, error) {
	globalLogLevel, err := c.getGlobalLogConfig(ctx)
	if err != nil {
	logger.Errorw(ctx, "unable-to-retrieve-global-log-config", log.Fields{"err": err})
	}

	componentLogConfig, err := c.getComponentLogConfig(ctx, globalLogLevel)
	if err != nil {
	return nil, err
	}

	finalLogConfig := make(map[string]string)
	for packageName, logLevel := range componentLogConfig {
	finalLogConfig[strings.ReplaceAll(packageName, "#", "/")] = logLevel
	}

	return finalLogConfig, nil
	}

	// load and apply the current configuration for component name
	// create hash of loaded configuration using GenerateLogConfigHash
	// if there is previous hash stored, compare the hash to stored hash
	// if there is any change will call UpdateLogLevels
	func (c *ComponentLogController) loadAndApplyLogConfig(ctx context.Context, logConfig map[string]string) error {
	currentLogHash, err := GenerateLogConfigHash(logConfig)
	if err != nil {
	return err
	}

	if c.logHash != currentLogHash {
	updateLogLevels(ctx, logConfig)
	c.logHash = currentLogHash
	} else {
	logger.Debug(ctx, "effective-loglevel-config-same-as-currently-active")
	}

	return nil
	}

	// createModifiedLogLevels loops through the activeLogLevels recieved from zap logger and updatedLogLevels recieved from buildUpdatedLogConfig
	// to identify and create map of modified Log Levels of 2 types:
	// - Packages for which log level has been changed
	// - Packages for which log level config has been cleared - set to default log level
	func createModifiedLogLevels(ctx context.Context, activeLogLevels, updatedLogLevels map[string]string) map[string]string {
	defaultLevel := updatedLogLevels[defaultLogLevelKey]

	modifiedLogLevels := make(map[string]string)
	for activeKey, activeLevel := range activeLogLevels {
	if _, exist := updatedLogLevels[activeKey]; !exist {
	if activeLevel != defaultLevel {
	modifiedLogLevels[activeKey] = defaultLevel
	}
	} else if activeLevel != updatedLogLevels[activeKey] {
	modifiedLogLevels[activeKey] = updatedLogLevels[activeKey]
	}
	}

	// Log warnings for all invalid packages for which log config has been set
	for key, value := range updatedLogLevels {
	if _, exist := activeLogLevels[key]; !exist {
	logger.Warnw(ctx, "ignoring-loglevel-set-for-invalid-package", log.Fields{"package": key, "log-level": value})
	}
	}

	return modifiedLogLevels
	}

	// updateLogLevels update the loglevels for the component
	// retrieve active confguration from logger
	// compare with entries one by one and apply
	func updateLogLevels(ctx context.Context, updatedLogConfig map[string]string) {

	activeLogLevels := getActiveLogLevels(ctx)
	changedLogLevels := createModifiedLogLevels(ctx, activeLogLevels, updatedLogConfig)

	// If no changed log levels are found, just return. It may happen on configuration of a invalid package
	if len(changedLogLevels) == 0 {
	logger.Debug(ctx, "no-change-in-effective-loglevel-config")
	return
	}

	logger.Debugw(ctx, "applying-log-level-for-modified-packages", log.Fields{"changed-log-levels": changedLogLevels})
	for key, level := range changedLogLevels {
	if key == defaultLogLevelKey {
	if l, err := log.StringToLogLevel(level); err == nil {
	log.SetDefaultLogLevel(l)
	}
	} else {
	if l, err := log.StringToLogLevel(level); err == nil {
	log.SetPackageLogLevel(key, l)
	}
	}
	}
	}

	// generate md5 hash of key value pairs appended into a single string
	// in order by key name
	func GenerateLogConfigHash(createHashLog map[string]string) ([16]byte, error) {
	createHashLogBytes := []byte{}
	levelData, err := json.Marshal(createHashLog)
	if err != nil {
	return [16]byte{}, err
	}
	createHashLogBytes = append(createHashLogBytes, levelData...)
	return md5.Sum(createHashLogBytes), nil
	}