fix: handle community shard unassignment and update

eth-node/bridge/geth/waku.go

@@ -69,6 +69,11 @@ func (w *gethWakuWrapper) SubscribeToPubsubTopic(topic string, optPublicKey *ecd
 	return errors.New("not available in WakuV1")
 }
 
+func (w *gethWakuWrapper) UnsubscribeFromPubsubTopic(topic string) error {
+	// not available in WakuV1
+	return errors.New("not available in WakuV1")
+}
+
 func (w *gethWakuWrapper) RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error) {
 	// not available in WakuV1
 	return nil, errors.New("not available in WakuV1")
@@ -79,6 +84,11 @@ func (w *gethWakuWrapper) StorePubsubTopicKey(topic string, privKey *ecdsa.Priva
 	return errors.New("not available in WakuV1")
 }
 
+func (w *gethWakuWrapper) RemovePubsubTopicKey(topic string) error {
+	// not available in WakuV1
+	return errors.New("not available in WakuV1")
+}
+
 // AddRelayPeer function only added for compatibility with waku V2
 func (w *gethWakuWrapper) AddRelayPeer(address string) (peer.ID, error) {
 	return "", errors.New("not available in WakuV1")

eth-node/bridge/geth/wakuv2.go

@@ -237,6 +237,10 @@ func (w *gethWakuV2Wrapper) SubscribeToPubsubTopic(topic string, optPublicKey *e
 	return w.waku.SubscribeToPubsubTopic(topic, optPublicKey)
 }
 
+func (w *gethWakuV2Wrapper) UnsubscribeFromPubsubTopic(topic string) error {
+	return w.waku.UnsubscribeFromPubsubTopic(topic)
+}
+
 func (w *gethWakuV2Wrapper) RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error) {
 	return w.waku.RetrievePubsubTopicKey(topic)
 }
@@ -245,6 +249,10 @@ func (w *gethWakuV2Wrapper) StorePubsubTopicKey(topic string, privKey *ecdsa.Pri
 	return w.waku.StorePubsubTopicKey(topic, privKey)
 }
 
+func (w *gethWakuV2Wrapper) RemovePubsubTopicKey(topic string) error {
+	return w.waku.RemovePubsubTopicKey(topic)
+}
+
 func (w *gethWakuV2Wrapper) AddStorePeer(address string) (peer.ID, error) {
 	return w.waku.AddStorePeer(address)
 }

eth-node/types/waku.go

@@ -90,10 +90,14 @@ type Waku interface {
 
 	SubscribeToPubsubTopic(topic string, optPublicKey *ecdsa.PublicKey) error
 
+	UnsubscribeFromPubsubTopic(topic string) error
+
 	StorePubsubTopicKey(topic string, privKey *ecdsa.PrivateKey) error
 
 	RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error)
 
+	RemovePubsubTopicKey(topic string) error
+
 	AddStorePeer(address string) (peer.ID, error)
 
 	AddRelayPeer(address string) (peer.ID, error)

protocol/communities/manager.go

@@ -1077,6 +1077,10 @@ func (m *Manager) DeleteCommunity(id types.HexBytes) error {
 
 func (m *Manager) UpdateShard(community *Community, shard *shard.Shard, clock uint64) error {
 	community.config.Shard = shard
+	if shard == nil {
+		return m.persistence.DeleteCommunityShard(community.ID())
+	}
+
 	return m.persistence.SaveCommunityShard(community.ID(), shard, clock)
 }
 
@@ -1086,9 +1090,6 @@ func (m *Manager) SetShard(communityID types.HexBytes, shard *shard.Shard) (*Com
 	if err != nil {
 		return nil, err
 	}
-	if !community.IsControlNode() {
-		return nil, errors.New("not admin or owner")
-	}
 
 	community.increaseClock()
 
@@ -1105,17 +1106,12 @@ func (m *Manager) SetShard(communityID types.HexBytes, shard *shard.Shard) (*Com
 	return community, nil
 }
 
-func (m *Manager) UpdatePubsubTopicPrivateKey(community *Community, privKey *ecdsa.PrivateKey) error {
-	community.SetPubsubTopicPrivateKey(privKey)
-
+func (m *Manager) UpdatePubsubTopicPrivateKey(topic string, privKey *ecdsa.PrivateKey) error {
 	if privKey != nil {
-		topic := community.PubsubTopic()
-		if err := m.transport.StorePubsubTopicKey(topic, privKey); err != nil {
-			return err
-		}
+		return m.transport.StorePubsubTopicKey(topic, privKey)
 	}
 
-	return nil
+	return m.transport.RemovePubsubTopicKey(topic)
 }
 
 // EditCommunity takes a description, updates the community with the description,

protocol/messenger_communities.go

@@ -715,6 +715,16 @@ func (m *Messenger) subscribeToCommunityShard(communityID []byte, shard *shard.S
 	return m.transport.SubscribeToPubsubTopic(pubsubTopic, pubK)
 }
 
+func (m *Messenger) unsubscribeFromShard(shard *shard.Shard) error {
+	if m.transport.WakuVersion() != 2 {
+		return nil
+	}
+
+	// TODO: this should probably be moved completely to transport once pubsub topic logic is implemented
+
+	return m.transport.UnsubscribeFromPubsubTopic(shard.PubsubTopic())
+}
+
 func (m *Messenger) joinCommunity(ctx context.Context, communityID types.HexBytes, forceJoin bool) (*MessengerResponse, error) {
 	logger := m.logger.Named("joinCommunity")
 
@@ -2053,26 +2063,57 @@ func (m *Messenger) SetCommunityShard(request *requests.SetCommunityShard) (*Mes
 		return nil, err
 	}
 
-	community, err := m.communitiesManager.SetShard(request.CommunityID, request.Shard)
+	community, err := m.communitiesManager.GetByID(request.CommunityID)
 	if err != nil {
 		return nil, err
 	}
 
-	var topicPrivKey *ecdsa.PrivateKey
-	if request.PrivateKey != nil {
-		topicPrivKey, err = crypto.ToECDSA(*request.PrivateKey)
-	} else {
-		topicPrivKey, err = crypto.GenerateKey()
+	if !community.IsControlNode() {
+		return nil, errors.New("not admin or owner")
 	}
+
+	// Reset the community private key
+	community.SetPubsubTopicPrivateKey(nil)
+
+	// Removing the private key (if it exist)
+	err = m.RemovePubsubTopicPrivateKey(community.PubsubTopic())
 	if err != nil {
 		return nil, err
 	}
 
-	err = m.communitiesManager.UpdatePubsubTopicPrivateKey(community, topicPrivKey)
+	// Unsubscribing from existing shard
+	if community.Shard() != nil {
+		err := m.unsubscribeFromShard(community.Shard())
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	community, err = m.communitiesManager.SetShard(request.CommunityID, request.Shard)
 	if err != nil {
 		return nil, err
 	}
 
+	if request.Shard != nil {
+		var topicPrivKey *ecdsa.PrivateKey
+		if request.PrivateKey != nil {
+			topicPrivKey, err = crypto.ToECDSA(*request.PrivateKey)
+		} else {
+			topicPrivKey, err = crypto.GenerateKey()
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		community.SetPubsubTopicPrivateKey(topicPrivKey)
+
+		err = m.communitiesManager.UpdatePubsubTopicPrivateKey(community.PubsubTopic(), topicPrivKey)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// TODO: Check
 	err = m.UpdateCommunityFilters(community)
 	if err != nil {
 		return nil, err
@@ -2094,6 +2135,10 @@ func (m *Messenger) SetCommunityShard(request *requests.SetCommunityShard) (*Mes
 	return response, nil
 }
 
+func (m *Messenger) RemovePubsubTopicPrivateKey(topic string) error {
+	return m.transport.RemovePubsubTopicKey(topic)
+}
+
 func (m *Messenger) UpdateCommunityFilters(community *communities.Community) error {
 	defaultFilters := m.DefaultFilters(community)
 	publicFiltersToInit := make([]transport.FiltersToInitialize, 0, len(defaultFilters)+len(community.Chats()))
@@ -2480,15 +2525,16 @@ func (m *Messenger) SendCommunityShardKey(community *communities.Community, pubk
 		return nil
 	}
 
+	keyBytes := make([]byte, 0)
 	key := community.PubsubTopicPrivateKey()
-	if key == nil {
-		return nil // No community shard key available
+	if key != nil {
+		keyBytes = crypto.FromECDSA(key)
 	}
 
 	communityShardKey := &protobuf.CommunityShardKey{
 		Clock:       community.Clock(),
 		CommunityId: community.ID(),
-		PrivateKey:  crypto.FromECDSA(key),
+		PrivateKey:  keyBytes,
 		Shard:       community.Shard().Protobuffer(),
 	}
 
@@ -2831,14 +2877,32 @@ func (m *Messenger) handleCommunityShardAndFiltersFromProto(community *communiti
 	}
 
 	var privKey *ecdsa.PrivateKey = nil
-	if message.PrivateKey != nil {
-		privKey, err = crypto.ToECDSA(message.PrivateKey)
+	if message.Shard != nil {
+		if message.PrivateKey != nil {
+			privKey, err = crypto.ToECDSA(message.PrivateKey)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	// Removing the existing private key (if any)
+	err = m.RemovePubsubTopicPrivateKey(community.PubsubTopic())
+	if err != nil {
+		return err
+	}
+
+	// Unsubscribing from existing shard
+	if community.Shard() != nil {
+		err := m.unsubscribeFromShard(community.Shard())
 		if err != nil {
 			return err
 		}
 	}
 
-	err = m.communitiesManager.UpdatePubsubTopicPrivateKey(community, privKey)
+	community.SetPubsubTopicPrivateKey(privKey)
+
+	err = m.communitiesManager.UpdatePubsubTopicPrivateKey(community.PubsubTopic(), privKey)
 	if err != nil {
 		return err
 	}

protocol/transport/transport.go

@@ -692,10 +692,25 @@ func (t *Transport) SubscribeToPubsubTopic(topic string, optPublicKey *ecdsa.Pub
 	return nil
 }
 
+// Unsubscribe from a pubsub topic
+func (t *Transport) UnsubscribeFromPubsubTopic(topic string) error {
+	if t.waku.Version() == 2 {
+		return t.waku.UnsubscribeFromPubsubTopic(topic)
+	}
+	return nil
+}
+
 func (t *Transport) StorePubsubTopicKey(topic string, privKey *ecdsa.PrivateKey) error {
 	return t.waku.StorePubsubTopicKey(topic, privKey)
 }
 
 func (t *Transport) RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error) {
 	return t.waku.RetrievePubsubTopicKey(topic)
 }
+
+func (t *Transport) RemovePubsubTopicKey(topic string) error {
+	if t.waku.Version() == 2 {
+		return t.waku.RemovePubsubTopicKey(topic)
+	}
+	return nil
+}

wakuv2/persistence/signed_messages.go

@@ -17,6 +17,7 @@ type ProtectedTopicsStore struct {
 
 	insertStmt       *sql.Stmt
 	fetchPrivKeyStmt *sql.Stmt
+	deleteStmt       *sql.Stmt
 }
 
 // Creates a new DB store using the db specified via options.
@@ -33,11 +34,17 @@ func NewProtectedTopicsStore(log *zap.Logger, db *sql.DB) (*ProtectedTopicsStore
 		return nil, err
 	}
 
+	deleteStmt, err := db.Prepare("DELETE FROM pubsubtopic_signing_key WHERE topic = ?")
+	if err != nil {
+		return nil, err
+	}
+
 	result := new(ProtectedTopicsStore)
 	result.log = log.Named("protected-topics-store")
 	result.db = db
 	result.insertStmt = insertStmt
 	result.fetchPrivKeyStmt = fetchPrivKeyStmt
+	result.deleteStmt = deleteStmt
 
 	return result, nil
 }
@@ -64,6 +71,11 @@ func (p *ProtectedTopicsStore) Insert(pubsubTopic string, privKey *ecdsa.Private
 	return err
 }
 
+func (p *ProtectedTopicsStore) Delete(pubsubTopic string) error {
+	_, err := p.deleteStmt.Exec(pubsubTopic)
+	return err
+}
+
 func (p *ProtectedTopicsStore) FetchPrivateKey(topic string) (privKey *ecdsa.PrivateKey, err error) {
 	var privKeyBytes []byte
 	err = p.fetchPrivKeyStmt.QueryRow(topic).Scan(&privKeyBytes)

wakuv2/waku.go

@@ -610,6 +610,18 @@ func (w *Waku) getPubsubTopic(topic string) string {
 	return topic
 }
 
+func (w *Waku) unsubscribeFromPubsubTopicWithWakuRelay(topic string) error {
+	topic = w.getPubsubTopic(topic)
+
+	if !w.node.Relay().IsSubscribed(topic) {
+		return nil
+	}
+
+	contentFilter := protocol.NewContentFilter(topic)
+
+	return w.node.Relay().Unsubscribe(w.ctx, contentFilter)
+}
+
 func (w *Waku) subscribeToPubsubTopicWithWakuRelay(topic string, pubkey *ecdsa.PublicKey) error {
 	if w.settings.LightClient {
 		return errors.New("only available for full nodes")
@@ -1535,6 +1547,18 @@ func (w *Waku) SubscribeToPubsubTopic(topic string, pubkey *ecdsa.PublicKey) err
 	return nil
 }
 
+func (w *Waku) UnsubscribeFromPubsubTopic(topic string) error {
+	topic = w.getPubsubTopic(topic)
+
+	if !w.settings.LightClient {
+		err := w.unsubscribeFromPubsubTopicWithWakuRelay(topic)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (w *Waku) RetrievePubsubTopicKey(topic string) (*ecdsa.PrivateKey, error) {
 	topic = w.getPubsubTopic(topic)
 	if w.protectedTopicStore == nil {
@@ -1553,6 +1577,15 @@ func (w *Waku) StorePubsubTopicKey(topic string, privKey *ecdsa.PrivateKey) erro
 	return w.protectedTopicStore.Insert(topic, privKey, &privKey.PublicKey)
 }
 
+func (w *Waku) RemovePubsubTopicKey(topic string) error {
+	topic = w.getPubsubTopic(topic)
+	if w.protectedTopicStore == nil {
+		return nil
+	}
+
+	return w.protectedTopicStore.Delete(topic)
+}
+
 func (w *Waku) StartDiscV5() error {
 	if w.node.DiscV5() == nil {
 		return errors.New("discv5 is not setup")