Use UDP dial to find default address for outbound traffic.

Set default bindAddr if it has not been explicitly provided be the user.

docker-compose.yaml

@@ -11,7 +11,6 @@ services:
       context: .
       dockerfile: ./server/Dockerfile
     environment:
-      - BINDADDR=0.0.0.0
       - PORT=7480
       - RAFTPORT=8000
       - MLPORT=7946
@@ -31,7 +30,6 @@ services:
       context: .
       dockerfile: ./server/Dockerfile
     environment:
-      - BINDADDR=0.0.0.0
       - PORT=7480
       - RAFTPORT=8000
       - MLPORT=7946
@@ -52,7 +50,6 @@ services:
       context: .
       dockerfile: ./server/Dockerfile
     environment:
-      - BINDADDR=0.0.0.0
       - PORT=7480
       - RAFTPORT=8000
       - MLPORT=7946

server/config.go

@@ -31,7 +31,7 @@ func GetConfig() Config {
 	http := flag.Bool("http", false, "Use HTTP protocol instead of raw TCP. Default is false")
 	serverId := flag.String("serverId", "1", "Server ID in raft cluster. Leave empty for client.")
 	joinAddr := flag.String("joinAddr", "", "Address of cluster member in a cluster to you want to join.")
-	bindAddr := flag.String("bindAddr", "127.0.0.1", "Address to bind the server to.")
+	bindAddr := flag.String("bindAddr", "", "Address to bind the server to.")
 	raftBindPort := flag.Int("raftPort", 7481, "Port to use for intra-cluster communication. Leave on the client.")
 	mlBindPort := flag.Int("mlPort", 7946, "Port to use for memberlist communication.")
 	config := flag.String(

server/main.go

@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"fmt"
 	"io"
+	"log"
 	"net"
 	"net/http"
 	"os"
@@ -103,13 +104,13 @@ func (server *Server) StartTCP() {
 		fmt.Printf("Starting TLS server at Address %s, Port %d...\n", conf.BindAddr, conf.Port)
 		cer, err := tls.LoadX509KeyPair(conf.Cert, conf.Key)
 		if err != nil {
-			panic(err)
+			log.Fatal(err)
 		}
 
 		if l, err := tls.Listen("tcp", fmt.Sprintf("%s:%d", conf.BindAddr, conf.Port), &tls.Config{
 			Certificates: []tls.Certificate{cer},
 		}); err != nil {
-			panic(err)
+			log.Fatal(err)
 		} else {
 			listener = l
 		}
@@ -119,7 +120,7 @@ func (server *Server) StartTCP() {
 		// TCP
 		fmt.Printf("Starting TCP server at Address %s, Port %d...\n", conf.BindAddr, conf.Port)
 		if l, err := net.Listen("tcp", fmt.Sprintf("%s:%d", conf.BindAddr, conf.Port)); err != nil {
-			panic(err)
+			log.Fatal(err)
 		} else {
 			listener = l
 		}
@@ -170,7 +171,7 @@ func (server *Server) Start() {
 	}
 
 	server.MemberListInit()
-	// server.RaftInit()
+	server.RaftInit()
 
 	if conf.HTTP {
 		server.StartHTTP()
@@ -188,6 +189,15 @@ func (server *Server) ShutDown() {
 func main() {
 	config := GetConfig()
 
+	// Default BindAddr if it's not set
+	if config.BindAddr == "" {
+		if addr, err := GetIPAddress(); err != nil {
+			log.Fatal(err)
+		} else {
+			config.BindAddr = addr
+		}
+	}
+
 	cancelCh := make(chan (os.Signal), 1)
 	signal.Notify(cancelCh, syscall.SIGINT, syscall.SIGTERM)
 

server/raft.go

@@ -15,6 +15,7 @@ func (server *Server) RaftInit() {
 	// Triggered after MemberList init
 
 	conf := server.config
+	fmt.Println(conf)
 
 	raftConfig := raft.DefaultConfig()
 	raftConfig.LocalID = raft.ServerID(conf.ServerID)
@@ -24,9 +25,10 @@ func (server *Server) RaftInit() {
 	raftSnapshotStore := raft.NewInmemSnapshotStore()
 
 	raftAddr := fmt.Sprintf("%s:%d", conf.BindAddr, conf.RaftBindPort)
+
 	raftAdvertiseAddr, err := net.ResolveTCPAddr("tcp", raftAddr)
 	if err != nil {
-		log.Fatal("Could not resolve advertise address.")
+		log.Fatal(err)
 	}
 
 	raftTransport, err := raft.NewTCPTransport(

server/utils.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"math"
 	"math/big"
+	"net"
 	"reflect"
 	"strings"
 	"time"
@@ -188,3 +189,17 @@ func RetryBackoff(b retry.Backoff, maxRetries uint64, jitter, cappedDuration, ma
 
 	return backoff
 }
+
+func GetIPAddress() (string, error) {
+	conn, err := net.Dial("udp", "8.8.8.8:80")
+
+	if err != nil {
+		return "", err
+	}
+
+	defer conn.Close()
+
+	localAddr := strings.Split(conn.LocalAddr().String(), ":")[0]
+
+	return localAddr, nil
+}