implement host option update channel feed. need to fix sigsegv bug when goroutine reads from closed channel

node/lux_node.go

@@ -48,6 +48,10 @@ func (node *LuxNode) GetStateLock() *sync.RWMutex {
 	return &node.stateLock
 }
 
+func (node *LuxNode) GetHostStateChannel() <-chan LuxHostState {
+	return node.state.GetStateChannel()
+}
+
 func (node *LuxNode) handleHeartbeat(packet *net.LuxPacket) {
 	if packet.ChannelType != net.LuxChannelExterior {
 		log.Error("heartbeat not on exterior!")

node/lux_node_state.go

@@ -19,17 +19,24 @@ func (state *LuxHostState) String() string {
 }
 
 type LuxNodeState struct {
-	hosts      map[proto.LuxID]*LuxHostState
+	hosts     map[proto.LuxID]*LuxHostState
+	stateChan chan LuxHostState
+
 	generation uint64
 }
 
 func NewNodeState() LuxNodeState {
 	return LuxNodeState{
 		hosts:      make(map[proto.LuxID]*LuxHostState),
+		stateChan:  make(chan LuxHostState),
 		generation: rand.Uint64(),
 	}
 }
 
+func (ns *LuxNodeState) GetStateChannel() <-chan LuxHostState {
+	return ns.stateChan
+}
+
 func (ns *LuxNodeState) RegisterHeartbeat(hostId proto.LuxID, hostState host.LuxState) {
 	// if we already have host, then update state and increment
 	if state, ok := ns.hosts[hostId]; ok {
@@ -42,7 +49,10 @@ func (ns *LuxNodeState) RegisterHeartbeat(hostId proto.LuxID, hostState host.Lux
 			Increment: 0,
 		}
 	}
-	// TODO: pass updated options to node controller
+
+	// we're making copy here instead of sending pointer,
+	// so receiver does not mutate it
+	ns.stateChan <- *ns.hosts[hostId]
 }
 
 // Merge current state and state received from node state multicast.
@@ -67,6 +77,8 @@ func (ns *LuxNodeState) Merge(new *LuxNodeState) {
 			// add new host state
 			ns.hosts[id] = newState
 		}
+		// let channel receivers know about new merged states
+		ns.stateChan <- *ns.hosts[id]
 	}
 }
 

tests/lux_node_test.go

@@ -39,5 +39,6 @@ func TestNodeHeartbeat(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	node.GetRouter().Recv()
+	hostState := <-node.GetHostStateChannel()
+	t.Log(hostState)
 }