wip

node-master.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"log"
+	"sync"
+	"time"
+)
+
+var (
+	isMaster      bool
+	masterNode    string
+	masterNodeMux sync.RWMutex
+)
+
+const (
+	heartbeatInterval = 5 * time.Second
+	heartbeatTimeout  = 15 * time.Second
+	electionTimeout   = 10 * time.Second
+)
+
+func sendHeartbeats() {
+	for {
+		if !isMaster {
+			return
+		}
+		for _, node := range peers {
+			err := sendMessage(node, authCode, "heartbeat", authCode)
+			if err != nil {
+				log.Printf("Error sending heartbeat to %s: %v", node, err)
+			}
+		}
+		time.Sleep(heartbeatInterval)
+	}
+}
+
+func checkMasterHeartbeat() {
+	for {
+		time.Sleep(heartbeatTimeout)
+		masterNodeMux.RLock()
+		if masterNode == authCode || masterNode == "" {
+			masterNodeMux.RUnlock()
+			continue
+		}
+		masterNodeMux.RUnlock()
+
+		masterNodeMux.Lock()
+		masterNode = ""
+		masterNodeMux.Unlock()
+		startElection()
+	}
+}
+
+func startElection() {
+	masterNodeMux.Lock()
+	defer masterNodeMux.Unlock()
+
+	for _, node := range peers {
+		err := sendMessage(node, authCode, "election", authCode)
+		if err != nil {
+			log.Printf("Error sending election message to %s: %v", node, err)
+		}
+	}
+
+	isMaster = true
+	go sendHeartbeats()
+}
+
+func handleHeartbeat(content string) {
+	masterNodeMux.Lock()
+	defer masterNodeMux.Unlock()
+	masterNode = content
+}
+
+func handleElection(content string) {
+	masterNodeMux.Lock()
+	defer masterNodeMux.Unlock()
+
+	if content < authCode {
+		masterNode = content
+	}
+}