Use MulticastGroup as map key and serialize under lock

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

dante.go

@@ -103,10 +103,9 @@ func (n *Nodes) GetDanteTxDeviceInGroup(groupIP net.IP) *Node {
 	defer n.mu.RUnlock()
 
 	group := ParseMulticastGroup(groupIP)
-	groupKey := group.String()
 	for _, node := range n.nodes {
 		if node.DanteTxChannels != "" && node.MulticastGroups != nil {
-			if _, exists := node.MulticastGroups[groupKey]; exists {
+			if _, exists := node.MulticastGroups[group]; exists {
 				return node
 			}
 		}

http.go

@@ -115,14 +115,26 @@ func ensureCert() error {
 }
 
 func (t *Tendrils) handleAPIStatus(w http.ResponseWriter, r *http.Request) {
-	status := t.GetStatus()
 	w.Header().Set("Content-Type", "application/json")
-	if err := json.NewEncoder(w).Encode(status); err != nil {
+	data, err := t.GetStatusJSON()
+	if err != nil {
 		log.Printf("[ERROR] failed to encode status: %v", err)
+		return
 	}
+	w.Write(data)
 }
 
-func (t *Tendrils) GetStatus() *StatusResponse {
+func (t *Tendrils) GetStatusJSON() ([]byte, error) {
+	t.nodes.mu.Lock()
+	t.nodes.expireMulticastMemberships()
+	t.nodes.expireArtNet()
+	t.nodes.expireSACN()
+	t.nodes.expireDante()
+	t.nodes.mu.Unlock()
+
+	t.nodes.mu.RLock()
+	defer t.nodes.mu.RUnlock()
+
 	var broadcastStats *BroadcastStatsResponse
 	if t.broadcast != nil {
 		stats := t.broadcast.GetStats()
@@ -132,13 +144,13 @@ func (t *Tendrils) GetStatus() *StatusResponse {
 	if config == nil {
 		config = &Config{}
 	}
-	return &StatusResponse{
+	return json.Marshal(&StatusResponse{
 		Config:         config,
-		Nodes:          t.getNodes(),
+		Nodes:          t.getNodesLocked(),
-		Links:          t.getLinks(),
+		Links:          t.getLinksLocked(),
 		Errors:         t.errors.GetErrors(),
 		BroadcastStats: broadcastStats,
-	}
+	})
 }
 
 func (t *Tendrils) handleClearError(w http.ResponseWriter, r *http.Request) {
@@ -175,7 +187,7 @@ func (t *Tendrils) handleAPIStatusStream(w http.ResponseWriter, r *http.Request)
 	defer t.unsubscribeSSE(subID)
 
 	sendStatus := func() error {
-		data, err := json.Marshal(t.GetStatus())
+		data, err := t.GetStatusJSON()
 		if err != nil {
 			log.Printf("[ERROR] failed to marshal status: %v", err)
 			return err
@@ -213,25 +225,13 @@ func (t *Tendrils) handleAPIStatusStream(w http.ResponseWriter, r *http.Request)
 	}
 }
 
-func (t *Tendrils) getNodes() []*Node {
+func (t *Tendrils) getNodesLocked() []*Node {
-	t.nodes.mu.Lock()
-	t.nodes.expireMulticastMemberships()
-	t.nodes.expireArtNet()
-	t.nodes.expireSACN()
-	t.nodes.expireDante()
-	t.nodes.mu.Unlock()
-
-	t.nodes.mu.RLock()
-	defer t.nodes.mu.RUnlock()
-
 	unreachableNodes := t.errors.GetUnreachableNodeSet()
 
 	nodes := make([]*Node, 0, len(t.nodes.nodes))
 	for _, node := range t.nodes.nodes {
-		n := new(Node)
+		node.Unreachable = unreachableNodes[node.ID]
-		*n = *node
+		nodes = append(nodes, node)
-		n.Unreachable = unreachableNodes[node.ID]
-		nodes = append(nodes, n)
 	}
 
 	sort.Slice(nodes, func(i, j int) bool {
@@ -248,10 +248,7 @@ func (t *Tendrils) getNodes() []*Node {
 }
 
 
-func (t *Tendrils) getLinks() []*Link {
+func (t *Tendrils) getLinksLocked() []*Link {
-	t.nodes.mu.RLock()
-	defer t.nodes.mu.RUnlock()
-
 	links := t.nodes.getDirectLinks()
 	sort.Slice(links, func(i, j int) bool {
 		if links[i].NodeA.DisplayName() != links[j].NodeA.DisplayName() {

multicast.go

@@ -65,13 +65,12 @@ func (n *Nodes) GetMulticastGroupMembers(groupIP net.IP) []*Node {
 	defer n.mu.RUnlock()
 
 	group := ParseMulticastGroup(groupIP)
-	groupKey := group.String()
 	var members []*Node
 	for _, node := range n.nodes {
 		if node.MulticastGroups == nil {
 			continue
 		}
-		if _, exists := node.MulticastGroups[groupKey]; exists {
+		if _, exists := node.MulticastGroups[group]; exists {
 			members = append(members, node)
 		}
 	}
@@ -93,9 +92,9 @@ func (n *Nodes) mergeMulticast(keep, merge *Node) {
 	if keep.MulticastGroups == nil {
 		keep.MulticastGroups = MulticastMembershipSet{}
 	}
-	for key, membership := range merge.MulticastGroups {
+	for group, lastSeen := range merge.MulticastGroups {
-		if existing, ok := keep.MulticastGroups[key]; !ok || membership.LastSeen.After(existing.LastSeen) {
+		if existing, ok := keep.MulticastGroups[group]; !ok || lastSeen.After(existing) {
-			keep.MulticastGroups[key] = membership
+			keep.MulticastGroups[group] = lastSeen
 		}
 	}
 }

types.go

@@ -218,30 +218,20 @@ func ParseMulticastGroup(ip net.IP) MulticastGroup {
 	return MulticastGroup{RawIP: ip.String()}
 }
 
-type MulticastMembership struct {
+type MulticastMembershipSet map[MulticastGroup]time.Time
-	Group    MulticastGroup
-	LastSeen time.Time
-}
-
-type MulticastMembershipSet map[string]*MulticastMembership
 
 func (s MulticastMembershipSet) Add(group MulticastGroup) {
-	key := group.String()
+	s[group] = time.Now()
-	if m, exists := s[key]; exists {
-		m.LastSeen = time.Now()
-	} else {
-		s[key] = &MulticastMembership{Group: group, LastSeen: time.Now()}
-	}
 }
 
 func (s MulticastMembershipSet) Remove(group MulticastGroup) {
-	delete(s, group.String())
+	delete(s, group)
 }
 
 func (s MulticastMembershipSet) Groups() []MulticastGroup {
 	result := make([]MulticastGroup, 0, len(s))
-	for _, m := range s {
+	for g := range s {
-		result = append(result, m.Group)
+		result = append(result, g)
 	}
 	sort.Slice(result, func(i, j int) bool {
 		return result[i].String() < result[j].String()
@@ -251,9 +241,9 @@ func (s MulticastMembershipSet) Groups() []MulticastGroup {
 
 func (s MulticastMembershipSet) SACNInputs() []SACNUniverse {
 	var result []SACNUniverse
-	for _, m := range s {
+	for g := range s {
-		if m.Group.IsSACN() {
+		if g.IsSACN() {
-			result = append(result, m.Group.SACNUniverse)
+			result = append(result, g.SACNUniverse)
 		}
 	}
 	sort.Slice(result, func(i, j int) bool { return result[i] < result[j] })
@@ -262,9 +252,9 @@ func (s MulticastMembershipSet) SACNInputs() []SACNUniverse {
 
 func (s MulticastMembershipSet) Expire(maxAge time.Duration) {
 	expireTime := time.Now().Add(-maxAge)
-	for key, m := range s {
+	for g, lastSeen := range s {
-		if m.LastSeen.Before(expireTime) {
+		if lastSeen.Before(expireTime) {
-			delete(s, key)
+			delete(s, g)
 		}
 	}
 }
@@ -419,43 +409,6 @@ func (n *Node) SACNInputs() []SACNUniverse {
 	return n.MulticastGroups.SACNInputs()
 }
 
-func (n *Node) MarshalJSON() ([]byte, error) {
-	type nodeJSON struct {
-		ID                 string                 `json:"id"`
-		Names              NameSet                `json:"names"`
-		Interfaces         InterfaceMap           `json:"interfaces"`
-		MACTableSize       int                    `json:"mac_table_size,omitempty"`
-		PoEBudget          *PoEBudget             `json:"poe_budget,omitempty"`
-		IsDanteClockMaster bool                   `json:"is_dante_clock_master,omitempty"`
-		DanteTxChannels    string                 `json:"dante_tx_channels,omitempty"`
-		MulticastGroups    MulticastMembershipSet `json:"multicast_groups,omitempty"`
-		ArtNetInputs       ArtNetUniverseSet      `json:"artnet_inputs,omitempty"`
-		ArtNetOutputs      ArtNetUniverseSet      `json:"artnet_outputs,omitempty"`
-		SACNInputs         []SACNUniverse         `json:"sacn_inputs,omitempty"`
-		SACNOutputs        SACNUniverseSet        `json:"sacn_outputs,omitempty"`
-		DanteTx            []*DantePeer           `json:"dante_tx,omitempty"`
-		DanteRx            []*DantePeer           `json:"dante_rx,omitempty"`
-		Unreachable        bool                   `json:"unreachable,omitempty"`
-	}
-	return json.Marshal(nodeJSON{
-		ID:                 n.ID,
-		Names:              n.Names,
-		Interfaces:         n.Interfaces,
-		MACTableSize:       n.MACTableSize(),
-		PoEBudget:          n.PoEBudget,
-		IsDanteClockMaster: n.IsDanteClockMaster,
-		DanteTxChannels:    n.DanteTxChannels,
-		MulticastGroups:    n.MulticastGroups,
-		ArtNetInputs:       n.ArtNetInputs,
-		ArtNetOutputs:      n.ArtNetOutputs,
-		SACNInputs:         n.SACNInputs(),
-		SACNOutputs:        n.SACNOutputs,
-		DanteTx:            n.DanteTx,
-		DanteRx:            n.DanteRx,
-		Unreachable:        n.Unreachable,
-	})
-}
-
 type DantePeer struct {
 	Node     *Node             `json:"node"`
 	Channels []string          `json:"channels,omitempty"`