simulation: fix tcp-local network simulation (#8)

* simulation: fix tcp-local network simulation

* fixup

3 files changed, 13 insertions, 2 deletions

diff --git a/cmd/dexcon-simulation-peer-server/main.go b/cmd/dexcon-simulation-peer-server/main.go
index 326ae45..3e13262 100644
--- a/cmd/dexcon-simulation-peer-server/main.go
+++ b/cmd/dexcon-simulation-peer-server/main.go
@@ -19,6 +19,8 @@ package main
 
 import (
 	"flag"
+	"log"
+	"os"
 
 	"github.com/dexon-foundation/dexon-consensus-core/simulation"
 )
@@ -28,6 +30,11 @@ var configFile = flag.String("config", "", "path to simulation config file")
 func main() {
 	flag.Parse()
 
+	if *configFile == "" {
+		log.Println("error: no config file specified")
+		os.Exit(1)
+	}
+
 	server := simulation.NewPeerServer()
 	server.Run(*configFile)
 }
diff --git a/simulation/peer-server.go b/simulation/peer-server.go
index 4a74fb7..90bcf33 100644
--- a/simulation/peer-server.go
+++ b/simulation/peer-server.go
@@ -68,7 +68,7 @@ func (p *PeerServer) Run(configPath string) {
 		defer p.peersMu.Unlock()
 
 		host, _, _ := net.SplitHostPort(r.RemoteAddr)
-		p.peers[id] = fmt.Sprintf("%s:%s", host, portString)
+		p.peers[id] = net.JoinHostPort(host, portString)
 		log.Printf("Peer %s joined from %s", id, p.peers[id])
 	}
 
diff --git a/simulation/tcp-network.go b/simulation/tcp-network.go
index 7640480..02475e1 100644
--- a/simulation/tcp-network.go
+++ b/simulation/tcp-network.go
@@ -50,9 +50,13 @@ func NewTCPNetwork(local bool, peerServer string) *TCPNetwork {
 	if !local {
 		port = peerPort
 	}
+	pServer := peerServer
+	if local {
+		pServer = "localhost"
+	}
 	return &TCPNetwork{
 		local:       local,
-		peerServer:  peerServer,
+		peerServer:  pServer,
 		port:        port,
 		endpoints:   make(map[types.ValidatorID]string),
 		recieveChan: make(chan interface{}, msgBufferSize),