support unsubscribe

Signed-off-by: Jiangnan Jia <jnan0806@gmail.com>

control_plane.go

@@ -17,7 +17,9 @@ package opensergo
 import (
 	"log"
 	"os"
+	"reflect"
 	"sync"
+	"time"
 
 	"github.com/opensergo/opensergo-control-plane/pkg/controller"
 	"github.com/opensergo/opensergo-control-plane/pkg/model"
@@ -43,7 +45,11 @@ func NewControlPlane() (*ControlPlane, error) {
 		return nil, err
 	}
 
-	cp.server = transport.NewServer(uint32(10246), []model.SubscribeRequestHandler{cp.handleSubscribeRequest})
+	handlers := []model.SubscribeRequestHandler{
+		cp.handleSubscribeRequest,
+		cp.handleUnSubscribeRequest,
+	}
+	cp.server = transport.NewServer(uint32(10246), handlers)
 	cp.operator = operator
 
 	hostname, herr := os.Hostname()
@@ -62,6 +68,10 @@ func (c *ControlPlane) Start() error {
 	if err != nil {
 		return err
 	}
+
+	// start the delete-connection goroutine
+	c.delConn()
+
 	// Run the transport server
 	err = c.server.Run()
 	if err != nil {
@@ -106,7 +116,24 @@ func (c *ControlPlane) sendMessageToStream(stream model.OpenSergoTransportStream
 	})
 }
 
+func (c *ControlPlane) sendAckToStream(stream model.OpenSergoTransportStream, ack string, status *trpb.Status, respId string) error {
+	if stream == nil {
+		return nil
+	}
+	return stream.SendMsg(&trpb.SubscribeResponse{
+		Status:       status,
+		Ack:          ack,
+		ControlPlane: c.protoDesc,
+		ResponseId:   respId,
+	})
+}
+
 func (c *ControlPlane) handleSubscribeRequest(clientIdentifier model.ClientIdentifier, request *trpb.SubscribeRequest, stream model.OpenSergoTransportStream) error {
+
+	if trpb.SubscribeOpType_SUBSCRIBE != request.OpType {
+		return nil
+	}
+
 	//var labels []model.LabelKV
 	//if request.Target.Labels != nil {
 	//	for _, label := range request.Target.Labels {
@@ -160,3 +187,140 @@ func (c *ControlPlane) handleSubscribeRequest(clientIdentifier model.ClientIdent
 	}
 	return nil
 }
+
+// handleUnSubscribeRequest handle the UnSubscribeRequest request from OpenSergo SDK.
+//
+// 1.remove cache of SubscribeTarget in Connection
+// 2.remove watcher if there is no SubscribeTarget for the same kind in Connection cache.
+func (c *ControlPlane) handleUnSubscribeRequest(clientIdentifier model.ClientIdentifier, request *trpb.SubscribeRequest, stream model.OpenSergoTransportStream) error {
+
+	if trpb.SubscribeOpType_UNSUBSCRIBE != request.OpType {
+		return nil
+	}
+
+	for _, kind := range request.Target.Kinds {
+		namespacedApp := model.NamespacedApp{
+			Namespace: request.Target.Namespace,
+			App:       request.Target.App,
+		}
+		// remove the relation of Connection and SubscribeTarget  from local cache
+		err := c.server.ConnectionManager().RemoveWithIdentifier(namespacedApp, kind, clientIdentifier)
+
+		if err != nil {
+			status := &trpb.Status{
+				// TODO: defined a new errorCode
+				Code:    transport.RegisterWatcherError,
+				Message: "Remove from watcher error",
+				Details: nil,
+			}
+			err = c.sendMessageToStream(stream, request.Target.Namespace, request.Target.App, kind, nil, status, request.RequestId)
+			if err != nil {
+				// TODO: log here
+			}
+			continue
+		}
+
+		// handle the SubscribeTarget-cache and crdCache in CRDWatcher, and remove watcher. only push into a chan named delSubscribeConnChan waiting for delete.
+		// 1. if there is no kind cached in current Connection, push subscribeConnInfo with an empty NamespaceApp into delSubscribeConnChan,
+		// then, will delete the watcher for CRD.
+		// 2. if the number of relation between Connection and SubscribeTarget < 1, then push subscribeConnInfo with current NamespaceApp into delSubscribeConnChan,
+		// then 1st, will delete the SubscribeTarget which is cached in current Connection
+		// 2nd, will delte  the watcher for CRD if there's no kind cached in current Connection
+		existConnection := c.server.ConnectionManager().ExistConnection(namespacedApp.Namespace, namespacedApp.App, kind)
+		if !existConnection {
+			delSubscribeConnChan <- delSubscribeConnInfo{
+				stream:       stream,
+				request:      request,
+				namespaceApp: model.NamespacedApp{},
+				kind:         kind,
+			}
+		} else {
+			targetConnections, _ := c.server.ConnectionManager().Get(request.Target.Namespace, request.Target.App, kind)
+			if len(targetConnections) < 1 {
+				delSubscribeConnChan <- delSubscribeConnInfo{
+					stream:       stream,
+					request:      request,
+					namespaceApp: namespacedApp,
+					kind:         kind,
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// delSubscribeConnChan a chan for delete the SubscribeTarget-cache and crdCache in CRDWatcher, and remove watcher to stop watching.
+var delSubscribeConnChan chan delSubscribeConnInfo
+
+type delSubscribeConnInfo struct {
+	stream       model.OpenSergoTransportStream
+	request      *trpb.SubscribeRequest
+	namespaceApp model.NamespacedApp
+	kind         string
+}
+
+// delConn a goroutine contains the logic of delete the SubscribeTarget-cache and crdCache in CRDWatcher, and remove watcher.
+//
+// 1. at the beginning of current goroutine, should wait for the status of server is started.
+//
+// 2. when receive a delSubscribeConnInfo from delSubscribeConnChan, waiting a silence time to prevent inaccurate data statistics caused by network jitter.
+//
+// after the silence time, is the actually logic of deleting local cache and removing watcher.
+func (c *ControlPlane) delConn() {
+	go func() {
+		// waiting for server is started.
+		for !c.server.IsStarted() {
+			time.Sleep(time.Duration(1) * time.Second)
+		}
+
+		// receive from delSubscribeConnChan
+		currDelConnInfo := <-delSubscribeConnChan
+		namespaceApp := currDelConnInfo.namespaceApp
+		kind := currDelConnInfo.kind
+		request := currDelConnInfo.request
+		stream := currDelConnInfo.stream
+
+		// wait a silence for network jitter
+		// TODO make time of sleep is configurable
+		time.Sleep(time.Duration(5) * time.Second)
+		var err error
+
+		// RemoveSubscribeTarget from CRDWatcher
+		// if namespaceApp is not an empty struct, means that need to delete SubscribeTarget cache in CRDWatcher
+		if !reflect.DeepEqual(namespaceApp, model.NamespacedApp{}) {
+			// re-count the number of SubscribeTarget
+			targetConnections, _ := c.server.ConnectionManager().Get(namespaceApp.Namespace, namespaceApp.App, kind)
+			if len(targetConnections) < 1 {
+				if crdWatcher, existed := c.operator.GetWatcher(kind); existed {
+					err = crdWatcher.RemoveSubscribeTarget(model.SubscribeTarget{
+						Namespace: namespaceApp.Namespace,
+						AppName:   namespaceApp.App,
+						Kind:      kind,
+					})
+				}
+			}
+		}
+
+		// remove the CRDWatch from KubernetesOperator, to stop watching the kind.
+		existConnection := c.server.ConnectionManager().ExistConnection(namespaceApp.Namespace, namespaceApp.App, kind)
+		if !existConnection {
+			c.operator.RemoveWatcher(model.SubscribeTarget{
+				Namespace: namespaceApp.Namespace,
+				AppName:   namespaceApp.App,
+				Kind:      kind,
+			})
+		}
+
+		// send ackMessage for UnSubscribeConfig request.
+		status := &trpb.Status{
+			Code:    transport.Success,
+			Message: "unSubscribe success",
+			Details: nil,
+		}
+		err = c.sendAckToStream(stream, transport.ACKFlag, status, request.RequestId)
+		if err != nil {
+			// TODO: log here
+		}
+	}()
+}

pkg/controller/crd_watcher.go

@@ -16,6 +16,7 @@ package controller
 
 import (
 	"context"
+	"go.uber.org/atomic"
 	"log"
 	"net/http"
 	"strconv"
@@ -56,6 +57,7 @@ type CRDWatcher struct {
 	crdGenerator    func() client.Object
 	sendDataHandler model.DataEntirePushHandler
 
+	deleted   *atomic.Bool
 	updateMux sync.RWMutex
 }
 
@@ -97,7 +99,24 @@ func (r *CRDWatcher) AddSubscribeTarget(target model.SubscribeTarget) error {
 }
 
 func (r *CRDWatcher) RemoveSubscribeTarget(target model.SubscribeTarget) error {
-	// TODO: implement me
+	// TODO: validate the target
+	if target.Kind != r.kind {
+		return errors.New("target kind mismatch, expected: " + target.Kind + ", r.kind: " + r.kind)
+	}
+	r.updateMux.Lock()
+	defer r.updateMux.Unlock()
+
+	// remove the subscribe-cache in this CRDWatcher
+	delete(r.subscribedList, target)
+	delete(r.subscribedNamespaces, target.Namespace)
+	delete(r.subscribedApps, target.NamespacedApp())
+
+	// delete the matched crdCache which comes from k8s
+	// TODO the 2nd param need fix to correct.
+	r.crdCache.DeleteByNamespaceApp(model.NamespacedApp{
+		Namespace: target.Namespace,
+		App:       target.AppName,
+	}, "")
 
 	return nil
 }
@@ -119,6 +138,14 @@ func (r *CRDWatcher) HasAnySubscribedOfApp(app model.NamespacedApp) bool {
 }
 
 func (r *CRDWatcher) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	// TODO optimize the logic of destroy the current controller
+	//     r.deleted.Load() is a flag marked the deleted status of controller
+	//     can not destroy the current controller
+	//
+	if r.deleted.Load() {
+		return ctrl.Result{}, nil
+	}
+
 	if !r.HasAnySubscribedOfNamespace(req.Namespace) {
 		// Ignore unmatched namespace
 		return ctrl.Result{Requeue: false, RequeueAfter: 0}, nil
@@ -216,9 +243,17 @@ func (r *CRDWatcher) GetRules(n model.NamespacedApp) ([]*anypb.Any, int64) {
 }
 
 func (r *CRDWatcher) SetupWithManager(mgr ctrl.Manager) error {
+	// TODO optimized delete logic here
+	r.deleted.Store(false)
 	return ctrl.NewControllerManagedBy(mgr).For(r.crdGenerator()).Complete(r)
 }
 
+func (r *CRDWatcher) ShutdownWithManager(mgr ctrl.Manager) error {
+	// TODO optimized delete logic here
+	r.deleted.Store(true)
+	return nil
+}
+
 func (r *CRDWatcher) translateCrdToProto(object client.Object) (*anypb.Any, error) {
 	var packRule *anypb.Any
 	var err error
@@ -338,6 +373,7 @@ func NewCRDWatcher(crdManager ctrl.Manager, kind model.SubscribeKind, crdGenerat
 		subscribedNamespaces: make(map[string]bool),
 		subscribedApps:       make(map[model.NamespacedApp]bool),
 		crdGenerator:         crdGenerator,
+		deleted:              atomic.NewBool(false),
 		crdCache:             NewCRDCache(kind),
 		sendDataHandler:      sendDataHandler,
 	}

pkg/controller/k8s_operator.go

@@ -129,6 +129,8 @@ func (k *KubernetesOperator) RegisterWatcher(target model.SubscribeTarget) (*CRD
 
 	existingWatcher, exists := k.controllers[target.Kind]
 	if exists {
+		// TODO optimized delete logic here
+		existingWatcher.deleted.Store(false)
 		if existingWatcher.HasSubscribed(target) {
 			// Target has been subscribed
 			return existingWatcher, nil
@@ -168,6 +170,8 @@ func (k *KubernetesOperator) AddWatcher(target model.SubscribeTarget) error {
 
 	existingWatcher, exists := k.controllers[target.Kind]
 	if exists && !existingWatcher.HasSubscribed(target) {
+		// TODO optimized delete logic here
+		existingWatcher.deleted.Store(false)
 		// TODO: think more about here
 		err = existingWatcher.AddSubscribeTarget(target)
 		if err != nil {
@@ -200,6 +204,22 @@ func (k *KubernetesOperator) AddWatcher(target model.SubscribeTarget) error {
 	return nil
 }
 
+func (k *KubernetesOperator) RemoveWatcher(target model.SubscribeTarget) error {
+	k.controllerMux.Lock()
+	defer k.controllerMux.Unlock()
+
+	crdWatch, exists := k.controllers[target.Kind]
+	if exists {
+		err := crdWatch.ShutdownWithManager(k.crdManager)
+		if err != nil {
+			// TODO add log
+		}
+		delete(k.controllers, target.Kind)
+	}
+
+	return nil
+}
+
 // Close exit the K8S KubernetesOperator
 func (k *KubernetesOperator) Close() error {
 	k.ctxCancel()

pkg/transport/grpc/connection.go

@@ -154,6 +154,26 @@ func (c *ConnectionManager) RemoveByIdentifier(identifier model.ClientIdentifier
 	return nil
 }
 
+func (c *ConnectionManager) RemoveWithIdentifier(namespacedApp model.NamespacedApp, kind string, identifier model.ClientIdentifier) error {
+	c.updateMux.Lock()
+	defer c.updateMux.Unlock()
+
+	err := c.removeInternal(namespacedApp, kind, identifier)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *ConnectionManager) ExistConnection(namespace, app, kind string) bool {
+	connections, success := c.Get(namespace, app, kind)
+	if success && len(connections) > 0 {
+		return true
+	}
+	return false
+}
+
 func NewConnectionManager() *ConnectionManager {
 	return &ConnectionManager{
 		connectionMap: make(map[model.NamespacedApp]map[string]ConnectionMap),

pkg/transport/grpc/server.go

@@ -61,6 +61,10 @@ func (s *Server) ComponentName() string {
 	return "OpenSergoUniversalTransportServer"
 }
 
+func (s *Server) IsStarted() bool {
+	return s.started.Load()
+}
+
 func (s *Server) Run() error {
 	if s.started.CAS(false, true) {
 		listener, err := net.Listen("tcp", fmt.Sprintf(":%d", s.port))