tagged features

common/taggedfeatures/holder.go

@@ -0,0 +1,84 @@
+package taggedfeatures
+
+import (
+	"context"
+	"github.com/v2fly/v2ray-core/v4/common/task"
+	"github.com/v2fly/v2ray-core/v4/features"
+	"reflect"
+	"sync"
+)
+
+type Holder struct {
+	access     *sync.RWMutex
+	features   map[string]features.Feature
+	memberType reflect.Type
+	ctx        context.Context
+}
+
+func NewHolder(ctx context.Context, memberType interface{}) *Holder {
+	return &Holder{
+		ctx:        ctx,
+		access:     &sync.RWMutex{},
+		features:   make(map[string]features.Feature),
+		memberType: reflect.TypeOf(memberType),
+	}
+}
+
+func (h *Holder) GetFeaturesByTag(tag string) (features.Feature, error) {
+	h.access.RLock()
+	defer h.access.RUnlock()
+	feature, ok := h.features[tag]
+	if !ok {
+		return nil, newError("unable to find feature with tag")
+	}
+	return feature, nil
+}
+
+func (h *Holder) AddFeaturesByTag(tag string, feature features.Feature) error {
+	h.access.Lock()
+	defer h.access.Unlock()
+	featureType := reflect.TypeOf(feature.Type())
+	if !featureType.AssignableTo(h.memberType) {
+		return newError("feature is not assignable to the base type")
+	}
+	h.features[tag] = feature
+	return nil
+}
+
+func (h *Holder) RemoveFeaturesByTag(tag string) error {
+	h.access.Lock()
+	defer h.access.Unlock()
+	delete(h.features, tag)
+	return nil
+}
+
+func (h *Holder) GetFeaturesTag() ([]string, error) {
+	h.access.RLock()
+	defer h.access.RUnlock()
+	var ret []string
+	for key, _ := range h.features {
+		ret = append(ret, key)
+	}
+	return ret, nil
+}
+
+func (h *Holder) Start() error {
+	h.access.Lock()
+	defer h.access.Unlock()
+	var startTasks []func() error
+	for _, v := range h.features {
+		startTasks = append(startTasks, v.Start)
+	}
+	return task.Run(h.ctx, startTasks...)
+}
+
+func (h *Holder) Close() error {
+	h.access.Lock()
+	defer h.access.Unlock()
+
+	var closeTasks []func() error
+	for _, v := range h.features {
+		closeTasks = append(closeTasks, v.Close)
+	}
+	return task.Run(h.ctx, closeTasks...)
+}

common/taggedfeatures/taggedfeatures.go

@@ -0,0 +1,3 @@
+package taggedfeatures
+
+//go:generate go run github.com/v2fly/v2ray-core/v4/common/errors/errorgen

features/feature.go

@@ -15,3 +15,7 @@ type Feature interface {
 func PrintDeprecatedFeatureWarning(feature string) {
 	newError("You are using a deprecated feature: " + feature + ". Please update your config file with latest configuration format, or update your client software.").WriteToLog()
 }
+
+type TaggedFeatures interface {
+	GetFeaturesByTag(tag string) (Feature, error)
+}