From d782eb26d845c924fe5e1e22630bdd17dd71d8c5 Mon Sep 17 00:00:00 2001
From: Simon Eisenmann <simon@struktur.de>
Date: Tue, 1 Mar 2016 10:36:01 +0100
Subject: [PATCH] Added startup bus event and a NATS client id.

---
 server.conf.in                              |  5 ++++-
 src/app/spreed-webrtc-server/bus_manager.go | 23 ++++++++++++++-------
 src/app/spreed-webrtc-server/main.go        |  3 ++-
 3 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/server.conf.in b/server.conf.in
index b9727df6..bbab48d2 100644
--- a/server.conf.in
+++ b/server.conf.in
@@ -202,4 +202,7 @@ enabled = false
 ; NATS server URL
 ;url = nats://127.0.0.1:4222
 ; NATS connect establish timeout in seconds
-;establishTimeout = 60
\ No newline at end of file
+;establishTimeout = 60
+; Use client_id to distinguish between multipe servers. The value is sent
+; together with every NATS request. Defaults to empty.
+;client_id =
diff --git a/src/app/spreed-webrtc-server/bus_manager.go b/src/app/spreed-webrtc-server/bus_manager.go
index b7bc2067..87b809e4 100644
--- a/src/app/spreed-webrtc-server/bus_manager.go
+++ b/src/app/spreed-webrtc-server/bus_manager.go
@@ -29,6 +29,7 @@ import (
 )
 
 const (
+	BusManagerStartup    = "startup"
 	BusManagerOffer      = "offer"
 	BusManagerAnswer     = "answer"
 	BusManagerBye        = "bye"
@@ -45,6 +46,7 @@ type BusManager interface {
 // A BusTrigger is a container to serialize trigger events
 // for the bus backend.
 type BusTrigger struct {
+	Id      string
 	Name    string
 	From    string
 	Payload string      `json:",omitempty"`
@@ -63,24 +65,29 @@ type busManager struct {
 // NewBusManager creates and initializes a new BusMager with the
 // provided flags for NATS support. It is intended to connect the
 // backend bus with a easy to use API to send and receive bus data.
-func NewBusManager(useNats bool, subjectPrefix string) BusManager {
+func NewBusManager(id string, useNats bool, subjectPrefix string) BusManager {
 	var b BusManager
+	var err error
 	if useNats {
-		var err error
-		b, err = newNatsBus(subjectPrefix)
+		b, err = newNatsBus(id, subjectPrefix)
 		if err == nil {
 			log.Println("Nats bus connected")
 		} else {
 			log.Println("Error connecting nats bus", err)
-			b = &noopBus{}
+			b = &noopBus{id}
 		}
 	} else {
-		b = &noopBus{}
+		b = &noopBus{id}
 	}
+	if err == nil {
+		b.Trigger(BusManagerStartup, id, "", nil)
+	}
+
 	return &busManager{b}
 }
 
 type noopBus struct {
+	id string
 }
 
 func (bus *noopBus) Trigger(name, from, payload string, data interface{}) error {
@@ -88,11 +95,12 @@ func (bus *noopBus) Trigger(name, from, payload string, data interface{}) error
 }
 
 type natsBus struct {
+	id     string
 	prefix string
 	ec     *nats.EncodedConn
 }
 
-func newNatsBus(prefix string) (*natsBus, error) {
+func newNatsBus(id, prefix string) (*natsBus, error) {
 	ec, err := EstablishNatsConnection(nil)
 	if err != nil {
 		return nil, err
@@ -100,12 +108,13 @@ func newNatsBus(prefix string) (*natsBus, error) {
 	if prefix == "" {
 		prefix = "channelling.trigger"
 	}
-	return &natsBus{prefix, ec}, nil
+	return &natsBus{id, prefix, ec}, nil
 }
 
 func (bus *natsBus) Trigger(name, from, payload string, data interface{}) (err error) {
 	if bus.ec != nil {
 		trigger := &BusTrigger{
+			Id:      bus.id,
 			Name:    name,
 			From:    from,
 			Payload: payload,
diff --git a/src/app/spreed-webrtc-server/main.go b/src/app/spreed-webrtc-server/main.go
index e32a0f0c..181db45f 100644
--- a/src/app/spreed-webrtc-server/main.go
+++ b/src/app/spreed-webrtc-server/main.go
@@ -319,6 +319,7 @@ func runner(runtime phoenix.Runtime) error {
 			DefaultNatsEstablishTimeout = time.Duration(natsEstablishTimeout) * time.Second
 		}
 	}
+	natsClientId, _ := runtime.GetString("nats", "client_id")
 
 	// Load remaining configuration items.
 	config = NewConfig(runtime, tokenProvider != nil)
@@ -421,7 +422,7 @@ func runner(runtime phoenix.Runtime) error {
 	tickets := NewTickets(sessionSecret, encryptionSecret, computedRealm)
 	sessionManager := NewSessionManager(config, tickets, hub, roomManager, roomManager, buddyImages, sessionSecret)
 	statsManager := NewStatsManager(hub, roomManager, sessionManager)
-	busManager := NewBusManager(natsChannellingTrigger, natsChannellingTriggerSubject)
+	busManager := NewBusManager(natsClientId, natsChannellingTrigger, natsChannellingTriggerSubject)
 	channellingAPI := NewChannellingAPI(config, roomManager, tickets, sessionManager, statsManager, hub, hub, hub, busManager)
 
 	// Add handlers.