Add release level attribute to config option, improve internal handling

config/get.go

@@ -1,14 +1,7 @@
 package config
 
 import (
-	"sync"
-
-	"github.com/tevino/abool"
-)
-
-var (
-	validityFlag     = abool.NewBool(true)
-	validityFlagLock sync.RWMutex
+	"github.com/safing/portbase/log"
 )
 
 type (
@@ -22,19 +15,6 @@ type (
 	BoolOption func() bool
 )
 
-func getValidityFlag() *abool.AtomicBool {
-	validityFlagLock.RLock()
-	defer validityFlagLock.RUnlock()
-	return validityFlag
-}
-
-func resetValidityFlag() {
-	validityFlagLock.Lock()
-	defer validityFlagLock.Unlock()
-	validityFlag.SetTo(false)
-	validityFlag = abool.NewBool(true)
-}
-
 // GetAsString returns a function that returns the wanted string with high performance.
 func GetAsString(name string, fallback string) StringOption {
 	valid := getValidityFlag()
@@ -86,3 +66,127 @@ func GetAsBool(name string, fallback bool) BoolOption {
 		return value
 	}
 }
+
+// findValue find the correct value in the user or default config.
+func findValue(key string) interface{} {
+	optionsLock.RLock()
+	option, ok := options[key]
+	optionsLock.RUnlock()
+	if !ok {
+		log.Errorf("config: request for unregistered option: %s", key)
+		return nil
+	}
+
+	// lock option
+	option.Lock()
+	defer option.Unlock()
+
+	// check if option is active
+	optionActive := true
+	switch getReleaseLevel() {
+	case ReleaseLevelStable:
+		// In stable, only stable is active
+		optionActive = option.ReleaseLevel == ReleaseLevelStable
+	case ReleaseLevelBeta:
+		// In beta, only stable and beta are active
+		optionActive = option.ReleaseLevel == ReleaseLevelStable || option.ReleaseLevel == ReleaseLevelBeta
+	case ReleaseLevelExperimental:
+		// In experimental, everything is active
+		optionActive = true
+	}
+
+	if optionActive && option.activeValue != nil {
+		return option.activeValue
+	}
+
+	if option.activeDefaultValue != nil {
+		return option.activeDefaultValue
+	}
+
+	return option.DefaultValue
+}
+
+// findStringValue validates and returns the value with the given key.
+func findStringValue(key string, fallback string) (value string) {
+	result := findValue(key)
+	if result == nil {
+		return fallback
+	}
+	v, ok := result.(string)
+	if ok {
+		return v
+	}
+	return fallback
+}
+
+// findStringArrayValue validates and returns the value with the given key.
+func findStringArrayValue(key string, fallback []string) (value []string) {
+	result := findValue(key)
+	if result == nil {
+		return fallback
+	}
+
+	v, ok := result.([]interface{})
+	if ok {
+		new := make([]string, len(v))
+		for i, val := range v {
+			s, ok := val.(string)
+			if ok {
+				new[i] = s
+			} else {
+				return fallback
+			}
+		}
+		return new
+	}
+
+	return fallback
+}
+
+// findIntValue validates and returns the value with the given key.
+func findIntValue(key string, fallback int64) (value int64) {
+	result := findValue(key)
+	if result == nil {
+		return fallback
+	}
+	switch v := result.(type) {
+	case int:
+		return int64(v)
+	case int8:
+		return int64(v)
+	case int16:
+		return int64(v)
+	case int32:
+		return int64(v)
+	case int64:
+		return v
+	case uint:
+		return int64(v)
+	case uint8:
+		return int64(v)
+	case uint16:
+		return int64(v)
+	case uint32:
+		return int64(v)
+	case uint64:
+		return int64(v)
+	case float32:
+		return int64(v)
+	case float64:
+		return int64(v)
+	}
+	return fallback
+}
+
+// findBoolValue validates and returns the value with the given key.
+func findBoolValue(key string, fallback bool) (value bool) {
+	result := findValue(key)
+	if result == nil {
+		return fallback
+	}
+	v, ok := result.(bool)
+	if ok {
+		return v
+	}
+	return fallback
+}

config/get_test.go

@@ -24,13 +24,36 @@ func parseAndSetDefaultConfig(jsonData string) error {
 	return SetDefaultConfig(m)
 }
 
+func quickRegister(t *testing.T, key string, optType uint8, defaultValue interface{}) {
+	err := Register(&Option{
+		Name:           key,
+		Key:            key,
+		Description:    "test config",
+		ReleaseLevel:   ReleaseLevelStable,
+		ExpertiseLevel: ExpertiseLevelUser,
+		OptType:        optType,
+		DefaultValue:   defaultValue,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestGet(t *testing.T) {
+	// reset
+	options = make(map[string]*Option)
 
 	err := log.Start()
 	if err != nil {
 		t.Fatal(err)
 	}
 
+	quickRegister(t, "monkey", OptTypeInt, -1)
+	quickRegister(t, "zebras/zebra", OptTypeStringArray, []string{"a", "b"})
+	quickRegister(t, "elephant", OptTypeInt, -1)
+	quickRegister(t, "hot", OptTypeBool, false)
+	quickRegister(t, "cold", OptTypeBool, true)
+
 	err = parseAndSetConfig(`
   {
     "monkey": "1",
@@ -59,27 +82,27 @@ func TestGet(t *testing.T) {
 
 	monkey := GetAsString("monkey", "none")
 	if monkey() != "1" {
-		t.Fatalf("monkey should be 1, is %s", monkey())
+		t.Errorf("monkey should be 1, is %s", monkey())
 	}
 
 	zebra := GetAsStringArray("zebras/zebra", []string{})
 	if len(zebra()) != 2 || zebra()[0] != "black" || zebra()[1] != "white" {
-		t.Fatalf("zebra should be [\"black\", \"white\"], is %v", zebra())
+		t.Errorf("zebra should be [\"black\", \"white\"], is %v", zebra())
 	}
 
 	elephant := GetAsInt("elephant", -1)
 	if elephant() != 2 {
-		t.Fatalf("elephant should be 2, is %d", elephant())
+		t.Errorf("elephant should be 2, is %d", elephant())
 	}
 
 	hot := GetAsBool("hot", false)
 	if !hot() {
-		t.Fatalf("hot should be true, is %v", hot())
+		t.Errorf("hot should be true, is %v", hot())
 	}
 
 	cold := GetAsBool("cold", true)
 	if cold() {
-		t.Fatalf("cold should be false, is %v", cold())
+		t.Errorf("cold should be false, is %v", cold())
 	}
 
 	err = parseAndSetConfig(`
@@ -92,19 +115,126 @@ func TestGet(t *testing.T) {
 	}
 
 	if monkey() != "3" {
-		t.Fatalf("monkey should be 0, is %s", monkey())
+		t.Errorf("monkey should be 0, is %s", monkey())
 	}
 
 	if elephant() != 0 {
-		t.Fatalf("elephant should be 0, is %d", elephant())
+		t.Errorf("elephant should be 0, is %d", elephant())
 	}
 
 	zebra()
 	hot()
 
+	// concurrent
+	GetAsString("monkey", "none")()
+	GetAsStringArray("zebras/zebra", []string{})()
+	GetAsInt("elephant", -1)()
+	GetAsBool("hot", false)()
+
+}
+
+func TestReleaseLevel(t *testing.T) {
+	// reset
+	options = make(map[string]*Option)
+	registerReleaseLevelOption()
+
+	// setup
+	subsystemOption := &Option{
+		Name:           "test subsystem",
+		Key:            "subsystem/test",
+		Description:    "test config",
+		ReleaseLevel:   ReleaseLevelStable,
+		ExpertiseLevel: ExpertiseLevelUser,
+		OptType:        OptTypeBool,
+		DefaultValue:   false,
+	}
+	err := Register(subsystemOption)
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = SetConfigOption("subsystem/test", true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	testSubsystem := GetAsBool("subsystem/test", false)
+
+	// test option level stable
+	subsystemOption.ReleaseLevel = ReleaseLevelStable
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelStable)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelBeta)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelExperimental)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
+
+	// test option level beta
+	subsystemOption.ReleaseLevel = ReleaseLevelBeta
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelStable)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if testSubsystem() {
+		t.Errorf("should be inactive: opt=%s system=%s", subsystemOption.ReleaseLevel, releaseLevel)
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelBeta)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelExperimental)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
+
+	// test option level experimental
+	subsystemOption.ReleaseLevel = ReleaseLevelExperimental
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelStable)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if testSubsystem() {
+		t.Error("should be inactive")
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelBeta)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if testSubsystem() {
+		t.Error("should be inactive")
+	}
+	err = SetConfigOption(releaseLevelKey, ReleaseLevelExperimental)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !testSubsystem() {
+		t.Error("should be active")
+	}
 }
 
 func BenchmarkGetAsStringCached(b *testing.B) {
+	// reset
+	options = make(map[string]*Option)
+
 	// Setup
 	err := parseAndSetConfig(`
   {

config/layers.go

@@ -1,293 +0,0 @@
-package config
-
-import (
-	"errors"
-	"fmt"
-	"sync"
-
-	"github.com/safing/portbase/log"
-)
-
-var (
-	configLock sync.RWMutex
-
-	userConfig    = make(map[string]interface{})
-	defaultConfig = make(map[string]interface{})
-
-	// ErrInvalidJSON is returned by SetConfig and SetDefaultConfig if they receive invalid json.
-	ErrInvalidJSON = errors.New("json string invalid")
-
-	// ErrInvalidOptionType is returned by SetConfigOption and SetDefaultConfigOption if given an unsupported option type.
-	ErrInvalidOptionType = errors.New("invalid option value type")
-
-	changedSignal = make(chan struct{})
-)
-
-// Changed signals if any config option was changed.
-func Changed() <-chan struct{} {
-	configLock.RLock()
-	defer configLock.RUnlock()
-	return changedSignal
-}
-
-// triggerChange signals listeners that a config option was changed.
-func triggerChange() {
-	// must be locked!
-	close(changedSignal)
-	changedSignal = make(chan struct{})
-}
-
-// setConfig sets the (prioritized) user defined config.
-func setConfig(m map[string]interface{}) error {
-	configLock.Lock()
-	defer configLock.Unlock()
-	userConfig = m
-	resetValidityFlag()
-
-	go pushFullUpdate()
-	triggerChange()
-
-	return nil
-}
-
-// SetDefaultConfig sets the (fallback) default config.
-func SetDefaultConfig(m map[string]interface{}) error {
-	configLock.Lock()
-	defer configLock.Unlock()
-	defaultConfig = m
-	resetValidityFlag()
-
-	go pushFullUpdate()
-	triggerChange()
-
-	return nil
-}
-
-func validateValue(name string, value interface{}) (*Option, error) {
-	optionsLock.RLock()
-	defer optionsLock.RUnlock()
-
-	option, ok := options[name]
-	if !ok {
-		return nil, errors.New("config option does not exist")
-	}
-
-	switch v := value.(type) {
-	case string:
-		if option.OptType != OptTypeString {
-			return nil, fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), name, v)
-		}
-		if option.compiledRegex != nil {
-			if !option.compiledRegex.MatchString(v) {
-				return nil, fmt.Errorf("validation failed: string \"%s\" did not match regex for option %s", v, name)
-			}
-		}
-		return option, nil
-	case []string:
-		if option.OptType != OptTypeStringArray {
-			return nil, fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), name, v)
-		}
-		if option.compiledRegex != nil {
-			for pos, entry := range v {
-				if !option.compiledRegex.MatchString(entry) {
-					return nil, fmt.Errorf("validation failed: string \"%s\" at index %d did not match regex for option %s", entry, pos, name)
-				}
-			}
-		}
-		return option, nil
-	case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
-		if option.OptType != OptTypeInt {
-			return nil, fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), name, v)
-		}
-		if option.compiledRegex != nil {
-			if !option.compiledRegex.MatchString(fmt.Sprintf("%d", v)) {
-				return nil, fmt.Errorf("validation failed: number \"%d\" did not match regex for option %s", v, name)
-			}
-		}
-		return option, nil
-	case bool:
-		if option.OptType != OptTypeBool {
-			return nil, fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), name, v)
-		}
-		return option, nil
-	default:
-		return nil, fmt.Errorf("invalid option value type: %T", value)
-	}
-}
-
-// SetConfigOption sets a single value in the (prioritized) user defined config.
-func SetConfigOption(name string, value interface{}) error {
-	return setConfigOption(name, value, true)
-}
-
-func setConfigOption(name string, value interface{}, push bool) error {
-	configLock.Lock()
-	defer configLock.Unlock()
-
-	var err error
-
-	if value == nil {
-		delete(userConfig, name)
-	} else {
-		var option *Option
-		option, err = validateValue(name, value)
-		if err == nil {
-			userConfig[name] = value
-			if push {
-				go pushUpdate(option)
-			}
-		}
-	}
-
-	if err == nil {
-		resetValidityFlag()
-		go saveConfig() //nolint:errcheck // error is logged
-		triggerChange()
-	}
-
-	return err
-}
-
-// SetDefaultConfigOption sets a single value in the (fallback) default config.
-func SetDefaultConfigOption(name string, value interface{}) error {
-	return setDefaultConfigOption(name, value, true)
-}
-
-func setDefaultConfigOption(name string, value interface{}, push bool) error {
-	configLock.Lock()
-	defer configLock.Unlock()
-
-	var err error
-
-	if value == nil {
-		delete(defaultConfig, name)
-	} else {
-		var option *Option
-		option, err = validateValue(name, value)
-		if err == nil {
-			defaultConfig[name] = value
-			if push {
-				go pushUpdate(option)
-			}
-		}
-	}
-
-	if err == nil {
-		resetValidityFlag()
-		triggerChange()
-	}
-
-	return err
-}
-
-// findValue find the correct value in the user or default config.
-func findValue(name string) (result interface{}) {
-	configLock.RLock()
-	defer configLock.RUnlock()
-
-	result, ok := userConfig[name]
-	if ok {
-		return
-	}
-
-	result, ok = defaultConfig[name]
-	if ok {
-		return
-	}
-
-	optionsLock.RLock()
-	defer optionsLock.RUnlock()
-
-	option, ok := options[name]
-	if ok {
-		return option.DefaultValue
-	}
-
-	log.Errorf("config: request for unregistered option: %s", name)
-	return nil
-}
-
-// findStringValue validates and returns the value with the given name.
-func findStringValue(name string, fallback string) (value string) {
-	result := findValue(name)
-	if result == nil {
-		return fallback
-	}
-	v, ok := result.(string)
-	if ok {
-		return v
-	}
-	return fallback
-}
-
-// findStringArrayValue validates and returns the value with the given name.
-func findStringArrayValue(name string, fallback []string) (value []string) {
-	result := findValue(name)
-	if result == nil {
-		return fallback
-	}
-
-	v, ok := result.([]interface{})
-	if ok {
-		new := make([]string, len(v))
-		for i, val := range v {
-			s, ok := val.(string)
-			if ok {
-				new[i] = s
-			} else {
-				return fallback
-			}
-		}
-		return new
-	}
-
-	return fallback
-}
-
-// findIntValue validates and returns the value with the given name.
-func findIntValue(name string, fallback int64) (value int64) {
-	result := findValue(name)
-	if result == nil {
-		return fallback
-	}
-	switch v := result.(type) {
-	case int:
-		return int64(v)
-	case int8:
-		return int64(v)
-	case int16:
-		return int64(v)
-	case int32:
-		return int64(v)
-	case int64:
-		return v
-	case uint:
-		return int64(v)
-	case uint8:
-		return int64(v)
-	case uint16:
-		return int64(v)
-	case uint32:
-		return int64(v)
-	case uint64:
-		return int64(v)
-	case float32:
-		return int64(v)
-	case float64:
-		return int64(v)
-	}
-	return fallback
-}
-
-// findBoolValue validates and returns the value with the given name.
-func findBoolValue(name string, fallback bool) (value bool) {
-	result := findValue(name)
-	if result == nil {
-		return fallback
-	}
-	v, ok := result.(bool)
-	if ok {
-		return v
-	}
-	return fallback
-}

config/main.go

@@ -30,6 +30,7 @@ func prep() error {
 	if dataRoot == nil {
 		return errors.New("data root is not set")
 	}
+
 	return nil
 }
 

config/option.go

@@ -4,13 +4,14 @@ import (
 	"encoding/json"
 	"fmt"
 	"regexp"
+	"sync"
 
 	"github.com/tidwall/sjson"
 
 	"github.com/safing/portbase/database/record"
 )
 
-// Variable Type IDs for frontend Identification. Use ExternalOptType for extended types in the frontend.
+// Various attribute options. Use ExternalOptType for extended types in the frontend.
 const (
 	OptTypeString      uint8 = 1
 	OptTypeStringArray uint8 = 2
@@ -20,6 +21,10 @@ const (
 	ExpertiseLevelUser      uint8 = 1
 	ExpertiseLevelExpert    uint8 = 2
 	ExpertiseLevelDeveloper uint8 = 3
+
+	ReleaseLevelStable       = "stable"
+	ReleaseLevelBeta         = "beta"
+	ReleaseLevelExperimental = "experimental"
 )
 
 func getTypeName(t uint8) string {
@@ -39,48 +44,52 @@ func getTypeName(t uint8) string {
 
 // Option describes a configuration option.
 type Option struct {
+	sync.Mutex
+
 	Name        string
 	Key         string // in path format: category/sub/key
 	Description string
 
-	ExpertiseLevel  uint8
-	OptType         uint8
+	ReleaseLevel   string
+	ExpertiseLevel uint8
+	OptType        uint8
+
 	RequiresRestart bool
 	DefaultValue    interface{}
 
 	ExternalOptType string
 	ValidationRegex string
 
-	compiledRegex *regexp.Regexp
+	activeValue        interface{} // runtime value (loaded from config file or set by user)
+	activeDefaultValue interface{} // runtime default value (may be set internally)
+	compiledRegex      *regexp.Regexp
 }
 
 // Export expors an option to a Record.
-func (opt *Option) Export() (record.Record, error) {
-	data, err := json.Marshal(opt)
+func (option *Option) Export() (record.Record, error) {
+	option.Lock()
+	defer option.Unlock()
+
+	data, err := json.Marshal(option)
 	if err != nil {
 		return nil, err
 	}
 
-	configLock.RLock()
-	defer configLock.RUnlock()
-
-	userValue, ok := userConfig[opt.Key]
-	if ok {
-		data, err = sjson.SetBytes(data, "Value", userValue)
+	if option.activeValue != nil {
+		data, err = sjson.SetBytes(data, "Value", option.activeValue)
 		if err != nil {
 			return nil, err
 		}
 	}
 
-	defaultValue, ok := defaultConfig[opt.Key]
-	if ok {
-		data, err = sjson.SetBytes(data, "DefaultValue", defaultValue)
+	if option.activeDefaultValue != nil {
+		data, err = sjson.SetBytes(data, "DefaultValue", option.activeDefaultValue)
 		if err != nil {
 			return nil, err
 		}
 	}
 
-	r, err := record.NewWrapper(fmt.Sprintf("config:%s", opt.Key), nil, record.JSON, data)
+	r, err := record.NewWrapper(fmt.Sprintf("config:%s", option.Key), nil, record.JSON, data)
 	if err != nil {
 		return nil, err
 	}

config/persistence.go

@@ -14,30 +14,54 @@ var (
 )
 
 func loadConfig() error {
+	// check if persistence is configured
+	if configFilePath == "" {
+		return nil
+	}
+
+	// read config file
 	data, err := ioutil.ReadFile(configFilePath)
 	if err != nil {
 		return err
 	}
 
-	m, err := JSONToMap(data)
+	// convert to map
+	newValues, err := JSONToMap(data)
 	if err != nil {
 		return err
 	}
 
-	return setConfig(m)
+	// apply
+	return setConfig(newValues)
 }
 
-func saveConfig() (err error) {
-	data, err := MapToJSON(userConfig)
-	if err == nil {
-		err = ioutil.WriteFile(configFilePath, data, 0600)
+func saveConfig() error {
+	// check if persistence is configured
+	if configFilePath == "" {
+		return nil
 	}
 
+	// extract values
+	activeValues := make(map[string]interface{})
+	optionsLock.RLock()
+	for key, option := range options {
+		option.Lock()
+		if option.activeValue != nil {
+			activeValues[key] = option.activeValue
+		}
+		option.Unlock()
+	}
+	optionsLock.RUnlock()
+
+	// convert to JSON
+	data, err := MapToJSON(activeValues)
 	if err != nil {
 		log.Errorf("config: failed to save config: %s", err)
+		return err
 	}
 
-	return err
+	// write file
+	return ioutil.WriteFile(configFilePath, data, 0600)
 }
 
 // JSONToMap parses and flattens a hierarchical json object.
@@ -73,18 +97,10 @@ func flatten(rootMap, subMap map[string]interface{}, subKey string) {
 	}
 }
 
-// MapToJSON expands a flattened map and returns it as json.
-func MapToJSON(mapData map[string]interface{}) ([]byte, error) {
-	configLock.RLock()
-	defer configLock.RUnlock()
-
-	new := make(map[string]interface{})
-	for key, value := range mapData {
-		new[key] = value
-	}
-
-	expand(new)
-	return json.MarshalIndent(new, "", "  ")
+// MapToJSON expands a flattened map and returns it as json. The map is altered in the process.
+func MapToJSON(values map[string]interface{}) ([]byte, error) {
+	expand(values)
+	return json.MarshalIndent(values, "", "  ")
 }
 
 // expand expands a flattened map.

config/registry.go

@@ -21,8 +21,9 @@ func Register(option *Option) error {
 	if option.Name == "" ||
 		option.Key == "" ||
 		option.Description == "" ||
+		option.OptType == 0 ||
 		option.ExpertiseLevel == 0 ||
-		option.OptType == 0 {
+		option.ReleaseLevel == "" {
 		return ErrIncompleteCall
 	}
 

config/registry_test.go

@@ -5,12 +5,15 @@ import (
 )
 
 func TestRegistry(t *testing.T) {
+	// reset
+	options = make(map[string]*Option)
 
 	if err := Register(&Option{
 		Name:            "name",
 		Key:             "key",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeString,
 		DefaultValue:    "default",
 		ValidationRegex: "^(banana|water)$",
@@ -22,7 +25,8 @@ func TestRegistry(t *testing.T) {
 		Name:            "name",
 		Key:             "key",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         0,
 		DefaultValue:    "default",
 		ValidationRegex: "^[A-Z][a-z]+$",
@@ -34,7 +38,8 @@ func TestRegistry(t *testing.T) {
 		Name:            "name",
 		Key:             "key",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeString,
 		DefaultValue:    "default",
 		ValidationRegex: "[",

config/release.go

@@ -0,0 +1,57 @@
+package config
+
+import (
+	"fmt"
+	"sync"
+)
+
+const (
+	releaseLevelKey = "core/release_level"
+)
+
+var (
+	releaseLevel     = ReleaseLevelStable
+	releaseLevelLock sync.Mutex
+)
+
+func init() {
+	registerReleaseLevelOption()
+}
+
+func registerReleaseLevelOption() {
+	err := Register(&Option{
+		Name:        "Release Selection",
+		Key:         releaseLevelKey,
+		Description: "Select maturity level of features that should be available",
+
+		OptType:        OptTypeString,
+		ExpertiseLevel: ExpertiseLevelExpert,
+		ReleaseLevel:   ReleaseLevelStable,
+
+		RequiresRestart: false,
+		DefaultValue:    ReleaseLevelStable,
+
+		ExternalOptType: "string list",
+		ValidationRegex: fmt.Sprintf("^(%s|%s|%s)$", ReleaseLevelStable, ReleaseLevelBeta, ReleaseLevelExperimental),
+	})
+	if err != nil {
+		panic(err)
+	}
+}
+
+func updateReleaseLevel() {
+	new := findStringValue(releaseLevelKey, "")
+	releaseLevelLock.Lock()
+	if new == "" {
+		releaseLevel = ReleaseLevelStable
+	} else {
+		releaseLevel = new
+	}
+	releaseLevelLock.Unlock()
+}
+
+func getReleaseLevel() string {
+	releaseLevelLock.Lock()
+	defer releaseLevelLock.Unlock()
+	return releaseLevel
+}

config/set.go

@@ -0,0 +1,207 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+
+	"github.com/tevino/abool"
+)
+
+var (
+	// ErrInvalidJSON is returned by SetConfig and SetDefaultConfig if they receive invalid json.
+	ErrInvalidJSON = errors.New("json string invalid")
+
+	// ErrInvalidOptionType is returned by SetConfigOption and SetDefaultConfigOption if given an unsupported option type.
+	ErrInvalidOptionType = errors.New("invalid option value type")
+
+	validityFlag     = abool.NewBool(true)
+	validityFlagLock sync.RWMutex
+
+	changedSignal     = make(chan struct{})
+	changedSignalLock sync.Mutex
+)
+
+func getValidityFlag() *abool.AtomicBool {
+	validityFlagLock.RLock()
+	defer validityFlagLock.RUnlock()
+	return validityFlag
+}
+
+// Changed signals if any config option was changed.
+func Changed() <-chan struct{} {
+	changedSignalLock.Lock()
+	defer changedSignalLock.Unlock()
+	return changedSignal
+}
+
+func signalChanges() {
+	// refetch and save release level
+	updateReleaseLevel()
+
+	// reset validity flag
+	validityFlagLock.Lock()
+	validityFlag.SetTo(false)
+	validityFlag = abool.NewBool(true)
+	validityFlagLock.Unlock()
+
+	// trigger change signal: signal listeners that a config option was changed.
+	changedSignalLock.Lock()
+	close(changedSignal)
+	changedSignal = make(chan struct{})
+	changedSignalLock.Unlock()
+}
+
+// setConfig sets the (prioritized) user defined config.
+func setConfig(newValues map[string]interface{}) error {
+	optionsLock.Lock()
+	for key, option := range options {
+		newValue, ok := newValues[key]
+		option.Lock()
+		if ok {
+			option.activeValue = newValue
+		} else {
+			option.activeValue = nil
+		}
+		option.Unlock()
+	}
+	optionsLock.Unlock()
+
+	signalChanges()
+	go pushFullUpdate()
+	return nil
+}
+
+// SetDefaultConfig sets the (fallback) default config.
+func SetDefaultConfig(newValues map[string]interface{}) error {
+	optionsLock.Lock()
+	for key, option := range options {
+		newValue, ok := newValues[key]
+		option.Lock()
+		if ok {
+			option.activeDefaultValue = newValue
+		} else {
+			option.activeDefaultValue = nil
+		}
+		option.Unlock()
+	}
+	optionsLock.Unlock()
+
+	signalChanges()
+	go pushFullUpdate()
+	return nil
+}
+
+func validateValue(option *Option, value interface{}) error {
+	switch v := value.(type) {
+	case string:
+		if option.OptType != OptTypeString {
+			return fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), option.Key, v)
+		}
+		if option.compiledRegex != nil {
+			if !option.compiledRegex.MatchString(v) {
+				return fmt.Errorf("validation failed: string \"%s\" did not match regex for option %s", v, option.Key)
+			}
+		}
+		return nil
+	case []string:
+		if option.OptType != OptTypeStringArray {
+			return fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), option.Key, v)
+		}
+		if option.compiledRegex != nil {
+			for pos, entry := range v {
+				if !option.compiledRegex.MatchString(entry) {
+					return fmt.Errorf("validation failed: string \"%s\" at index %d did not match regex for option %s", entry, pos, option.Key)
+				}
+			}
+		}
+		return nil
+	case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
+		if option.OptType != OptTypeInt {
+			return fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), option.Key, v)
+		}
+		if option.compiledRegex != nil {
+			if !option.compiledRegex.MatchString(fmt.Sprintf("%d", v)) {
+				return fmt.Errorf("validation failed: number \"%d\" did not match regex for option %s", v, option.Key)
+			}
+		}
+		return nil
+	case bool:
+		if option.OptType != OptTypeBool {
+			return fmt.Errorf("expected type %s for option %s, got type %T", getTypeName(option.OptType), option.Key, v)
+		}
+		return nil
+	default:
+		return fmt.Errorf("invalid option value type: %T", value)
+	}
+}
+
+// SetConfigOption sets a single value in the (prioritized) user defined config.
+func SetConfigOption(key string, value interface{}) error {
+	return setConfigOption(key, value, true)
+}
+
+func setConfigOption(key string, value interface{}, push bool) (err error) {
+	optionsLock.Lock()
+	option, ok := options[key]
+	optionsLock.Unlock()
+	if !ok {
+		return fmt.Errorf("config option %s does not exist", key)
+	}
+
+	option.Lock()
+	if value == nil {
+		option.activeValue = nil
+	} else {
+		err = validateValue(option, value)
+		if err == nil {
+			option.activeValue = value
+		}
+	}
+	option.Unlock()
+	if err != nil {
+		return err
+	}
+
+	// finalize change, activate triggers
+	signalChanges()
+	if push {
+		go pushUpdate(option)
+	}
+	return saveConfig()
+}
+
+// SetDefaultConfigOption sets a single value in the (fallback) default config.
+func SetDefaultConfigOption(key string, value interface{}) error {
+	return setDefaultConfigOption(key, value, true)
+}
+
+func setDefaultConfigOption(key string, value interface{}, push bool) (err error) {
+	optionsLock.Lock()
+	option, ok := options[key]
+	optionsLock.Unlock()
+	if !ok {
+		return fmt.Errorf("config option %s does not exist", key)
+	}
+
+	option.Lock()
+	if value == nil {
+		option.activeDefaultValue = nil
+	} else {
+		err = validateValue(option, value)
+		if err == nil {
+			option.activeDefaultValue = value
+		}
+	}
+	option.Unlock()
+	if err != nil {
+		return err
+	}
+
+	// finalize change, activate triggers
+	signalChanges()
+	if push {
+		go pushUpdate(option)
+	}
+	return saveConfig()
+}

config/set_test.go

@@ -4,6 +4,8 @@ package config
 import "testing"
 
 func TestLayersGetters(t *testing.T) {
+	// reset
+	options = make(map[string]*Option)
 
 	mapData, err := JSONToMap([]byte(`
 		{
@@ -79,12 +81,15 @@ func TestLayersGetters(t *testing.T) {
 }
 
 func TestLayersSetters(t *testing.T) {
+	// reset
+	options = make(map[string]*Option)
 
 	Register(&Option{
 		Name:            "name",
 		Key:             "monkey",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeString,
 		DefaultValue:    "banana",
 		ValidationRegex: "^(banana|water)$",
@@ -93,7 +98,8 @@ func TestLayersSetters(t *testing.T) {
 		Name:            "name",
 		Key:             "zebras/zebra",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeStringArray,
 		DefaultValue:    []string{"black", "white"},
 		ValidationRegex: "^[a-z]+$",
@@ -102,7 +108,8 @@ func TestLayersSetters(t *testing.T) {
 		Name:            "name",
 		Key:             "elephant",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeInt,
 		DefaultValue:    2,
 		ValidationRegex: "",
@@ -111,7 +118,8 @@ func TestLayersSetters(t *testing.T) {
 		Name:            "name",
 		Key:             "hot",
 		Description:     "description",
-		ExpertiseLevel:  1,
+		ReleaseLevel:    ReleaseLevelStable,
+		ExpertiseLevel:  ExpertiseLevelUser,
 		OptType:         OptTypeBool,
 		DefaultValue:    true,
 		ValidationRegex: "",
@@ -180,8 +188,8 @@ func TestLayersSetters(t *testing.T) {
 	if err := SetDefaultConfigOption("elephant", nil); err != nil {
 		t.Error(err)
 	}
-	if err := SetDefaultConfigOption("invalid_delete", nil); err != nil {
-		t.Error(err)
+	if err := SetDefaultConfigOption("invalid_delete", nil); err == nil {
+		t.Error("should fail")
 	}
 
 }