fix: filter sub issues (#1123)

waku/v2/api/filter.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"time"
 
+	"github.com/google/uuid"
 	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/waku-org/go-waku/waku/v2/protocol"
 	"github.com/waku-org/go-waku/waku/v2/protocol/filter"
@@ -38,26 +39,32 @@ type Sub struct {
 	cancel                context.CancelFunc
 	log                   *zap.Logger
 	closing               chan string
+	isNodeOnline          bool //indicates if node has connectivity, this helps subscribe loop takes decision as to resubscribe or not.
+	resubscribeInProgress bool
+	id                    string
 }
 
 // Subscribe
-func Subscribe(ctx context.Context, wf *filter.WakuFilterLightNode, contentFilter protocol.ContentFilter, config FilterConfig, log *zap.Logger) (*Sub, error) {
+func Subscribe(ctx context.Context, wf *filter.WakuFilterLightNode, contentFilter protocol.ContentFilter, config FilterConfig, log *zap.Logger, online bool) (*Sub, error) {
 	sub := new(Sub)
+	sub.id = uuid.NewString()
 	sub.wf = wf
 	sub.ctx, sub.cancel = context.WithCancel(ctx)
 	sub.subs = make(subscription.SubscriptionSet)
 	sub.DataCh = make(chan *protocol.Envelope, MultiplexChannelBuffer)
 	sub.ContentFilter = contentFilter
 	sub.Config = config
-	sub.log = log.Named("filter-api")
-	sub.log.Debug("filter subscribe params", zap.Int("maxPeers", config.MaxPeers), zap.Stringer("contentFilter", contentFilter))
-	subs, err := sub.subscribe(contentFilter, sub.Config.MaxPeers)
+	sub.log = log.Named("filter-api").With(zap.String("apisub-id", sub.id), zap.Stringer("content-filter", sub.ContentFilter))
+	sub.log.Debug("filter subscribe params", zap.Int("max-peers", config.MaxPeers))
+	sub.isNodeOnline = online
 	sub.closing = make(chan string, config.MaxPeers)
-	if err != nil {
-		return nil, err
-	}
+	if online {
+		subs, err := sub.subscribe(contentFilter, sub.Config.MaxPeers)
+		if err == nil {
 			sub.multiplex(subs)
-	go sub.waitOnSubClose()
+		}
+	}
+	go sub.subscriptionLoop()
 	return sub, nil
 }
 
@@ -65,32 +72,51 @@ func (apiSub *Sub) Unsubscribe() {
 	apiSub.cancel()
 }
 
-func (apiSub *Sub) waitOnSubClose() {
+func (apiSub *Sub) SetNodeState(online bool) {
+	apiSub.isNodeOnline = online
+}
+
+func (apiSub *Sub) subscriptionLoop() {
+	ticker := time.NewTicker(5 * time.Second)
+	defer ticker.Stop()
 	for {
 		select {
+		case <-ticker.C:
+			if apiSub.isNodeOnline && len(apiSub.subs) < apiSub.Config.MaxPeers &&
+				!apiSub.resubscribeInProgress && len(apiSub.closing) < apiSub.Config.MaxPeers {
+				apiSub.closing <- ""
+			}
 		case <-apiSub.ctx.Done():
-			apiSub.log.Debug("apiSub context: Done()")
+			apiSub.log.Debug("apiSub context: done")
 			apiSub.cleanup()
 			return
 		case subId := <-apiSub.closing:
-			//trigger closing and resubscribe flow for subscription.
-			apiSub.closeAndResubscribe(subId)
-
+			apiSub.resubscribeInProgress = true
+			//trigger resubscribe flow for subscription.
+			apiSub.checkAndResubscribe(subId)
 		}
 	}
 }
 
-func (apiSub *Sub) closeAndResubscribe(subId string) {
-	apiSub.log.Debug("sub closeAndResubscribe", zap.String("subID", subId))
+func (apiSub *Sub) checkAndResubscribe(subId string) {
+
+	var failedPeer peer.ID
+	if subId != "" {
+		apiSub.log.Debug("subscription close and resubscribe", zap.String("sub-id", subId), zap.Stringer("content-filter", apiSub.ContentFilter))
 
 		apiSub.subs[subId].Close()
-	failedPeer := apiSub.subs[subId].PeerID
+		failedPeer = apiSub.subs[subId].PeerID
 		delete(apiSub.subs, subId)
+	}
+	apiSub.log.Debug("subscription status", zap.Int("sub-count", len(apiSub.subs)), zap.Stringer("content-filter", apiSub.ContentFilter))
+	if apiSub.isNodeOnline && len(apiSub.subs) < apiSub.Config.MaxPeers {
 		apiSub.resubscribe(failedPeer)
+	}
+	apiSub.resubscribeInProgress = false
 }
 
 func (apiSub *Sub) cleanup() {
-	apiSub.log.Debug("Cleaning up subscription", zap.Stringer("config", apiSub.Config))
+	apiSub.log.Debug("cleaning up subscription", zap.Stringer("config", apiSub.Config))
 
 	for _, s := range apiSub.subs {
 		_, err := apiSub.wf.UnsubscribeWithSubscription(apiSub.ctx, s)
@@ -100,25 +126,25 @@ func (apiSub *Sub) cleanup() {
 		}
 	}
 	close(apiSub.DataCh)
-
 }
 
 // Attempts to resubscribe on topics that lack subscriptions
 func (apiSub *Sub) resubscribe(failedPeer peer.ID) {
 	// Re-subscribe asynchronously
 	existingSubCount := len(apiSub.subs)
-	apiSub.log.Debug("subscribing again", zap.Stringer("contentFilter", apiSub.ContentFilter), zap.Int("numPeers", apiSub.Config.MaxPeers-existingSubCount))
+	apiSub.log.Debug("subscribing again", zap.Int("num-peers", apiSub.Config.MaxPeers-existingSubCount))
 	var peersToExclude peer.IDSlice
+	if failedPeer != "" { //little hack, couldn't find a better way to do it
 		peersToExclude = append(peersToExclude, failedPeer)
+	}
 	for _, sub := range apiSub.subs {
 		peersToExclude = append(peersToExclude, sub.PeerID)
 	}
 	subs, err := apiSub.subscribe(apiSub.ContentFilter, apiSub.Config.MaxPeers-existingSubCount, peersToExclude...)
 	if err != nil {
+		apiSub.log.Debug("failed to resubscribe for filter", zap.Error(err))
 		return
-	} //Not handling scenario where all requested subs are not received as that will get handled in next cycle.
-
-	apiSub.log.Debug("resubscribe(): before range newSubs")
+	} //Not handling scenario where all requested subs are not received as that should get handled from user of the API.
 
 	apiSub.multiplex(subs)
 }
@@ -131,35 +157,34 @@ func (apiSub *Sub) subscribe(contentFilter protocol.ContentFilter, peerCount int
 		options = append(options, filter.WithPeer(p))
 	}
 	if len(peersToExclude) > 0 {
-		apiSub.log.Debug("subscribing with peersToExclude", zap.Stringer("peersToExclude", peersToExclude[0]))
+		apiSub.log.Debug("subscribing with peers to exclude", zap.Stringers("excluded-peers", peersToExclude))
 		options = append(options, filter.WithPeersToExclude(peersToExclude...))
 	}
 	subs, err := apiSub.wf.Subscribe(apiSub.ctx, contentFilter, options...)
 
 	if err != nil {
+		//Inform of error, so that resubscribe can be triggered if required
+		if len(apiSub.closing) < apiSub.Config.MaxPeers {
+			apiSub.closing <- ""
+		}
 		if len(subs) > 0 {
-			// Partial Failure, for now proceed as we don't expect this to happen wrt specific topics.
-			// Rather it can happen in case subscription with one of the peer fails.
-			// This can further get automatically handled at resubscribe,
-			apiSub.log.Error("partial failure in Filter subscribe", zap.Error(err), zap.Int("successCount", len(subs)))
+			// Partial Failure, which means atleast 1 subscription is successful
+			apiSub.log.Debug("partial failure in filter subscribe", zap.Error(err), zap.Int("success-count", len(subs)))
 			return subs, nil
 		}
-		// In case of complete subscription failure, application or user needs to handle and probably retry based on error
-		// TODO: Once filter error handling indicates specific error, this can be addressed based on the error at this layer.
+		// TODO: Once filter error handling indicates specific error, this can be handled better.
 		return nil, err
 	}
-
 	return subs, nil
 }
 
 func (apiSub *Sub) multiplex(subs []*subscription.SubscriptionDetails) {
-
 	// Multiplex onto single channel
 	// Goroutines will exit once sub channels are closed
 	for _, subDetails := range subs {
 		apiSub.subs[subDetails.ID] = subDetails
 		go func(subDetails *subscription.SubscriptionDetails) {
-			apiSub.log.Debug("New multiplex", zap.String("subID", subDetails.ID))
+			apiSub.log.Debug("new multiplex", zap.String("sub-id", subDetails.ID))
 			for env := range subDetails.C {
 				apiSub.DataCh <- env
 			}
@@ -169,8 +194,7 @@ func (apiSub *Sub) multiplex(subs []*subscription.SubscriptionDetails) {
 			case <-apiSub.ctx.Done():
 				return
 			case <-subDetails.Closing:
-				apiSub.log.Debug("sub closing", zap.String("subID", subDetails.ID))
-
+				apiSub.log.Debug("sub closing", zap.String("sub-id", subDetails.ID))
 				apiSub.closing <- subDetails.ID
 			}
 		}(subDetails)

waku/v2/api/filter_test.go

@@ -48,7 +48,7 @@ func (s *FilterApiTestSuite) TestSubscribe() {
 	s.Require().Equal(contentFilter.PubsubTopic, s.TestTopic)
 
 	s.Log.Info("About to perform API Subscribe()")
-	apiSub, err := Subscribe(context.Background(), s.LightNode, contentFilter, apiConfig, s.Log)
+	apiSub, err := Subscribe(context.Background(), s.LightNode, contentFilter, apiConfig, s.Log, true)
 	s.Require().NoError(err)
 	s.Require().Equal(apiSub.ContentFilter, contentFilter)
 	s.Log.Info("Subscribed")

waku/v2/protocol/filter/client.go

@@ -591,7 +591,7 @@ func (wf *WakuFilterLightNode) UnsubscribeWithSubscription(ctx context.Context,
 	sub.Close()
 
 	result := &WakuFilterPushResult{}
-
+	wf.log.Debug("unsubscribing subscription", zap.String("sub-id", sub.ID), zap.Stringer("content-filter", sub.ContentFilter))
 	if !wf.subscriptions.Has(sub.PeerID, sub.ContentFilter) {
 		// Last sub for this [peer, contentFilter] pair
 		err = wf.unsubscribeFromServer(ctx, params.requestID, sub.PeerID, sub.ContentFilter)
@@ -599,6 +599,8 @@ func (wf *WakuFilterLightNode) UnsubscribeWithSubscription(ctx context.Context,
 			Err:    err,
 			PeerID: sub.PeerID,
 		})
+		wf.log.Debug("unsubscribed subscription", zap.String("sub-id", sub.ID), zap.Stringer("content-filter", sub.ContentFilter), zap.Error(err))
+
 	}
 	return result, err
 

waku/v2/protocol/subscription/subscription_details.go

@@ -112,6 +112,7 @@ func (s *SubscriptionDetails) SetClosing() {
 	s.Lock()
 	defer s.Unlock()
 	if !s.Closed {
+		s.Closed = true
 		s.Closing <- true
 	}
 }

waku/v2/protocol/subscription/subscriptions_map.go

@@ -142,6 +142,11 @@ func (sub *SubscriptionsMap) Delete(subscription *SubscriptionDetails) error {
 	contentFilter := subscription.ContentFilter
 	delete(peerSubscription.SubsPerPubsubTopic[contentFilter.PubsubTopic], subscription.ID)
 
+	if len(peerSubscription.SubsPerPubsubTopic[contentFilter.PubsubTopic]) == 0 {
+		sub.logger.Debug("no more subs for pubsubTopic for this peer", zap.Stringer("id", subscription.PeerID), zap.String("pubsubtopic", contentFilter.PubsubTopic))
+		delete(peerSubscription.SubsPerPubsubTopic, contentFilter.PubsubTopic)
+	}
+
 	// Decrease the number of subscriptions for this (pubsubTopic, contentTopic) pair
 	for contentTopic := range contentFilter.ContentTopics {
 		sub.decreaseSubFor(contentFilter.PubsubTopic, contentTopic)

waku/v2/protocol/subscription/subscriptions_map_test.go

@@ -49,9 +49,6 @@ func TestSubscriptionMapAppend(t *testing.T) {
 	err := sub.Close()
 	require.NoError(t, err)
 	require.True(t, sub.Closed)
-
-	err = sub.Close()
-	require.NoError(t, err)
 }
 
 func TestSubscriptionClear(t *testing.T) {