Added helloworld go example, repaired SendChannelMessage in world

utils/nats/helloworld/helloworld.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/nats-io/go-nats"
+	"github.com/xackery/rebuildeq/go/eqproto"
+)
+
+func main() {
+	fmt.Println("Starting...")
+	var nc *nats.Conn
+	var err error
+
+	//create a nats connection, by default 127.0.0.1
+	if nc, err = nats.Connect(nats.DefaultURL); err != nil {
+		log.Fatal(err)
+	}
+	defer nc.Close()
+
+	//listen for any channel messages from game
+	go asyncChannelMessageSubscriber(nc) //async is recommended
+	//go  syncChannelMessageSubscriber() //sync is here as example
+
+	//send a channel message to broadcast channel
+	go testBroadcastMessage(nc, "Hello, World!")
+
+	time.Sleep(20 * time.Second)
+	fmt.Println("Exited after 20 seconds")
+}
+
+// asyncChannelMessageSubscriber is an example of how to subscribe
+// and invoke a function when a message is received
+func asyncChannelMessageSubscriber(nc *nats.Conn) {
+	nc.Subscribe("world.channel_message", func(m *nats.Msg) {
+		message := &eqproto.ChannelMessage{}
+		proto.Unmarshal(m.Data, message)
+		log.Println(message)
+	})
+	log.Println("Waiting on async messages...")
+	time.Sleep(10 * time.Second)
+	log.Println("Timed out after 10 seconds")
+}
+
+// syncChannelMessageSubscriber is an example of how to subscribe
+// and poll for messages syncronously
+func syncChannelMessageSubscriber(nc *nats.Conn) {
+
+	sub, err := nc.SubscribeSync("world.channel_message")
+	if err != nil {
+		log.Fatal(err)
+	}
+	var m *nats.Msg
+	if m, err = sub.NextMsg(10 * time.Second); err != nil {
+		log.Println("Timed out after 10 seconds", err.Error())
+		return
+	}
+
+	message := &eqproto.ChannelMessage{}
+	proto.Unmarshal(m.Data, message)
+	log.Println("Got message", message)
+}
+
+func testBroadcastMessage(nc *nats.Conn, msg string) {
+	message := &eqproto.ChannelMessage{
+		From:    "go",
+		Message: msg,
+		ChanNum: 5, //5 is ooc, 6 is bc
+	}
+	d, err := proto.Marshal(message)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if err = nc.Publish("world.channel_message", d); err != nil {
+		log.Println("Failed to publish:", err.Error())
+		return
+	}
+	log.Println("Sending message", message)
+}