/** * Standalone signaling server for the Nextcloud Spreed app. * Copyright (C) 2017 struktur AG * * @author Joachim Bauch * * @license GNU AGPL version 3 or any later version * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . */ package signaling import ( "context" "encoding/json" "fmt" "log" "reflect" "strconv" "sync" "sync/atomic" "time" "github.com/dlintw/goconf" "github.com/notedit/janus-go" ) const ( pluginVideoRoom = "janus.plugin.videoroom" keepaliveInterval = 30 * time.Second videoPublisherUserId = 1 screenPublisherUserId = 2 initialReconnectInterval = 1 * time.Second maxReconnectInterval = 32 * time.Second defaultMaxStreamBitrate = 1024 * 1024 defaultMaxScreenBitrate = 2048 * 1024 streamTypeVideo = "video" streamTypeScreen = "screen" ) var ( streamTypeUserIds = map[string]uint64{ streamTypeVideo: videoPublisherUserId, streamTypeScreen: screenPublisherUserId, } ) func getPluginValue(data janus.PluginData, pluginName string, key string) interface{} { if data.Plugin != pluginName { return nil } return data.Data[key] } func convertIntValue(value interface{}) (uint64, error) { switch t := value.(type) { case float64: if t < 0 { return 0, fmt.Errorf("Unsupported float64 number: %+v", t) } return uint64(t), nil case uint64: return t, nil case int64: if t < 0 { return 0, fmt.Errorf("Unsupported int64 number: %+v", t) } return uint64(t), nil case json.Number: r, err := t.Int64() if err != nil { return 0, err } else if r < 0 { return 0, fmt.Errorf("Unsupported JSON number: %+v", t) } return uint64(r), nil default: return 0, fmt.Errorf("Unknown number type: %+v", t) } } func getPluginIntValue(data janus.PluginData, pluginName string, key string) uint64 { val := getPluginValue(data, pluginName, key) if val == nil { return 0 } result, err := convertIntValue(val) if err != nil { log.Printf("Invalid value %+v for %s: %s", val, key, err) result = 0 } return result } func getPluginStringValue(data janus.PluginData, pluginName string, key string) string { val := getPluginValue(data, pluginName, key) if val == nil { return "" } strVal, ok := val.(string) if !ok { return "" } return strVal } // TODO(jojo): Lots of error handling still missing. type clientInterface interface { NotifyReconnected() } type mcuJanus struct { // 64-bit members that are accessed atomically must be 64-bit aligned. clientId uint64 url string mu sync.Mutex maxStreamBitrate int maxScreenBitrate int mcuTimeout time.Duration gw *JanusGateway session *JanusSession handle *JanusHandle closeChan chan bool muClients sync.Mutex clients map[clientInterface]bool publishers map[string]*mcuJanusPublisher publisherCreated Notifier publisherConnected Notifier reconnectTimer *time.Timer reconnectInterval time.Duration connectedSince time.Time onConnected atomic.Value onDisconnected atomic.Value } func emptyOnConnected() {} func emptyOnDisconnected() {} func NewMcuJanus(url string, config *goconf.ConfigFile) (Mcu, error) { maxStreamBitrate, _ := config.GetInt("mcu", "maxstreambitrate") if maxStreamBitrate <= 0 { maxStreamBitrate = defaultMaxStreamBitrate } maxScreenBitrate, _ := config.GetInt("mcu", "maxscreenbitrate") if maxScreenBitrate <= 0 { maxScreenBitrate = defaultMaxScreenBitrate } mcuTimeoutSeconds, _ := config.GetInt("mcu", "timeout") if mcuTimeoutSeconds <= 0 { mcuTimeoutSeconds = defaultMcuTimeoutSeconds } mcuTimeout := time.Duration(mcuTimeoutSeconds) * time.Second mcu := &mcuJanus{ url: url, maxStreamBitrate: maxStreamBitrate, maxScreenBitrate: maxScreenBitrate, mcuTimeout: mcuTimeout, closeChan: make(chan bool, 1), clients: make(map[clientInterface]bool), publishers: make(map[string]*mcuJanusPublisher), reconnectInterval: initialReconnectInterval, } mcu.onConnected.Store(emptyOnConnected) mcu.onDisconnected.Store(emptyOnDisconnected) mcu.reconnectTimer = time.AfterFunc(mcu.reconnectInterval, mcu.doReconnect) mcu.reconnectTimer.Stop() if err := mcu.reconnect(); err != nil { return nil, err } return mcu, nil } func (m *mcuJanus) disconnect() { if m.handle != nil { if _, err := m.handle.Detach(context.TODO()); err != nil { log.Printf("Error detaching handle %d: %s", m.handle.Id, err) } m.handle = nil } if m.session != nil { m.closeChan <- true if _, err := m.session.Destroy(context.TODO()); err != nil { log.Printf("Error destroying session %d: %s", m.session.Id, err) } m.session = nil } if m.gw != nil { if err := m.gw.Close(); err != nil { log.Println("Error while closing connection to MCU", err) } m.gw = nil } } func (m *mcuJanus) reconnect() error { m.disconnect() gw, err := NewJanusGateway(m.url, m) if err != nil { return err } m.gw = gw m.reconnectTimer.Stop() return nil } func (m *mcuJanus) doReconnect() { if err := m.reconnect(); err != nil { m.scheduleReconnect(err) return } if err := m.Start(); err != nil { m.scheduleReconnect(err) return } log.Println("Reconnection to Janus gateway successful") m.mu.Lock() m.publishers = make(map[string]*mcuJanusPublisher) m.publisherCreated.Reset() m.publisherConnected.Reset() m.reconnectInterval = initialReconnectInterval m.mu.Unlock() m.muClients.Lock() for client := range m.clients { go client.NotifyReconnected() } m.muClients.Unlock() } func (m *mcuJanus) scheduleReconnect(err error) { m.mu.Lock() defer m.mu.Unlock() m.reconnectTimer.Reset(m.reconnectInterval) if err == nil { log.Printf("Connection to Janus gateway was interrupted, reconnecting in %s", m.reconnectInterval) } else { log.Printf("Reconnect to Janus gateway failed (%s), reconnecting in %s", err, m.reconnectInterval) } m.reconnectInterval = m.reconnectInterval * 2 if m.reconnectInterval > maxReconnectInterval { m.reconnectInterval = maxReconnectInterval } } func (m *mcuJanus) ConnectionInterrupted() { m.scheduleReconnect(nil) m.notifyOnDisconnected() } func (m *mcuJanus) Start() error { ctx := context.TODO() info, err := m.gw.Info(ctx) if err != nil { return err } log.Printf("Connected to %s %s by %s", info.Name, info.VersionString, info.Author) if plugin, found := info.Plugins[pluginVideoRoom]; !found { return fmt.Errorf("Plugin %s is not supported", pluginVideoRoom) } else { log.Printf("Found %s %s by %s", plugin.Name, plugin.VersionString, plugin.Author) } if !info.DataChannels { return fmt.Errorf("Data channels are not supported") } else { log.Println("Data channels are supported") } if !info.FullTrickle { log.Println("WARNING: Full-Trickle is NOT enabled in Janus!") } else { log.Println("Full-Trickle is enabled") } log.Printf("Maximum bandwidth %d bits/sec per publishing stream", m.maxStreamBitrate) log.Printf("Maximum bandwidth %d bits/sec per screensharing stream", m.maxScreenBitrate) if m.session, err = m.gw.Create(ctx); err != nil { m.disconnect() return err } log.Println("Created Janus session", m.session.Id) m.connectedSince = time.Now() if m.handle, err = m.session.Attach(ctx, pluginVideoRoom); err != nil { m.disconnect() return err } log.Println("Created Janus handle", m.handle.Id) go m.run() m.notifyOnConnected() return nil } func (m *mcuJanus) registerClient(client clientInterface) { m.muClients.Lock() m.clients[client] = true m.muClients.Unlock() } func (m *mcuJanus) unregisterClient(client clientInterface) { m.muClients.Lock() delete(m.clients, client) m.muClients.Unlock() } func (m *mcuJanus) run() { ticker := time.NewTicker(keepaliveInterval) defer ticker.Stop() loop: for { select { case <-ticker.C: m.sendKeepalive() case <-m.closeChan: break loop } } } func (m *mcuJanus) Stop() { m.disconnect() m.reconnectTimer.Stop() } func (m *mcuJanus) Reload(config *goconf.ConfigFile) { } func (m *mcuJanus) SetOnConnected(f func()) { if f == nil { f = emptyOnConnected } m.onConnected.Store(f) } func (m *mcuJanus) notifyOnConnected() { f := m.onConnected.Load().(func()) f() } func (m *mcuJanus) SetOnDisconnected(f func()) { if f == nil { f = emptyOnDisconnected } m.onDisconnected.Store(f) } func (m *mcuJanus) notifyOnDisconnected() { f := m.onDisconnected.Load().(func()) f() } type mcuJanusConnectionStats struct { Url string `json:"url"` Connected bool `json:"connected"` Publishers int64 `json:"publishers"` Clients int64 `json:"clients"` Uptime *time.Time `json:"uptime,omitempty"` } func (m *mcuJanus) GetStats() interface{} { result := mcuJanusConnectionStats{ Url: m.url, } if m.session != nil { result.Connected = true result.Uptime = &m.connectedSince } m.mu.Lock() result.Publishers = int64(len(m.publishers)) m.mu.Unlock() m.muClients.Lock() result.Clients = int64(len(m.clients)) m.muClients.Unlock() return result } func (m *mcuJanus) sendKeepalive() { ctx := context.TODO() if _, err := m.session.KeepAlive(ctx); err != nil { log.Println("Could not send keepalive request", err) if e, ok := err.(*janus.ErrorMsg); ok { switch e.Err.Code { case JANUS_ERROR_SESSION_NOT_FOUND: m.scheduleReconnect(err) } } } } type mcuJanusClient struct { mcu *mcuJanus listener McuListener mu sync.Mutex // nolint id uint64 session uint64 roomId uint64 streamType string handle *JanusHandle handleId uint64 closeChan chan bool deferred chan func() handleEvent func(event *janus.EventMsg) handleHangup func(event *janus.HangupMsg) handleDetached func(event *janus.DetachedMsg) handleConnected func(event *janus.WebRTCUpMsg) handleSlowLink func(event *janus.SlowLinkMsg) handleMedia func(event *janus.MediaMsg) } func (c *mcuJanusClient) Id() string { return strconv.FormatUint(c.id, 10) } func (c *mcuJanusClient) StreamType() string { return c.streamType } func (c *mcuJanusClient) Close(ctx context.Context) { } func (c *mcuJanusClient) SendMessage(ctx context.Context, message *MessageClientMessage, data *MessageClientMessageData, callback func(error, map[string]interface{})) { } func (c *mcuJanusClient) closeClient(ctx context.Context) bool { if handle := c.handle; handle != nil { c.handle = nil c.closeChan <- true if _, err := handle.Detach(ctx); err != nil { if e, ok := err.(*janus.ErrorMsg); !ok || e.Err.Code != JANUS_ERROR_HANDLE_NOT_FOUND { log.Println("Could not detach client", handle.Id, err) } } return true } return false } func (c *mcuJanusClient) run(handle *JanusHandle, closeChan chan bool) { loop: for { select { case msg := <-handle.Events: switch t := msg.(type) { case *janus.EventMsg: c.handleEvent(t) case *janus.HangupMsg: c.handleHangup(t) case *janus.DetachedMsg: c.handleDetached(t) case *janus.MediaMsg: c.handleMedia(t) case *janus.WebRTCUpMsg: c.handleConnected(t) case *janus.SlowLinkMsg: c.handleSlowLink(t) case *TrickleMsg: c.handleTrickle(t) default: log.Println("Received unsupported event type", msg, reflect.TypeOf(msg)) } case f := <-c.deferred: f() case <-closeChan: break loop } } } func (c *mcuJanusClient) sendOffer(ctx context.Context, offer map[string]interface{}, callback func(error, map[string]interface{})) { handle := c.handle if handle == nil { callback(ErrNotConnected, nil) return } configure_msg := map[string]interface{}{ "request": "configure", "audio": true, "video": true, "data": true, } answer_msg, err := handle.Message(ctx, configure_msg, offer) if err != nil { callback(err, nil) return } callback(nil, answer_msg.Jsep) } func (c *mcuJanusClient) sendAnswer(ctx context.Context, answer map[string]interface{}, callback func(error, map[string]interface{})) { handle := c.handle if handle == nil { callback(ErrNotConnected, nil) return } start_msg := map[string]interface{}{ "request": "start", "room": c.roomId, } start_response, err := handle.Message(ctx, start_msg, answer) if err != nil { callback(err, nil) return } log.Println("Started listener", start_response) callback(nil, nil) } func (c *mcuJanusClient) sendCandidate(ctx context.Context, candidate interface{}, callback func(error, map[string]interface{})) { handle := c.handle if handle == nil { callback(ErrNotConnected, nil) return } if _, err := handle.Trickle(ctx, candidate); err != nil { callback(err, nil) return } callback(nil, nil) } func (c *mcuJanusClient) handleTrickle(event *TrickleMsg) { if event.Candidate.Completed { c.listener.OnIceCompleted(c) } else { c.listener.OnIceCandidate(c, event.Candidate) } } func (c *mcuJanusClient) selectStream(ctx context.Context, substream int, temporal int, callback func(error, map[string]interface{})) { handle := c.handle if handle == nil { callback(ErrNotConnected, nil) return } if substream < 0 && temporal < 0 { callback(nil, nil) return } configure_msg := map[string]interface{}{ "request": "configure", } if substream >= 0 { configure_msg["substream"] = substream } if temporal >= 0 { configure_msg["temporal"] = temporal } _, err := handle.Message(ctx, configure_msg, nil) if err != nil { callback(err, nil) return } callback(nil, nil) } type publisherStatsCounter struct { mu sync.Mutex streamTypes map[string]bool subscribers map[string]bool } func (c *publisherStatsCounter) Reset() { c.mu.Lock() defer c.mu.Unlock() count := len(c.subscribers) for streamType := range c.streamTypes { statsMcuPublisherStreamTypesCurrent.WithLabelValues(streamType).Dec() statsMcuSubscriberStreamTypesCurrent.WithLabelValues(streamType).Sub(float64(count)) } c.streamTypes = nil c.subscribers = nil } func (c *publisherStatsCounter) EnableStream(streamType string, enable bool) { c.mu.Lock() defer c.mu.Unlock() if enable == c.streamTypes[streamType] { return } if enable { if c.streamTypes == nil { c.streamTypes = make(map[string]bool) } c.streamTypes[streamType] = true statsMcuPublisherStreamTypesCurrent.WithLabelValues(streamType).Inc() statsMcuSubscriberStreamTypesCurrent.WithLabelValues(streamType).Add(float64(len(c.subscribers))) } else { delete(c.streamTypes, streamType) statsMcuPublisherStreamTypesCurrent.WithLabelValues(streamType).Dec() statsMcuSubscriberStreamTypesCurrent.WithLabelValues(streamType).Sub(float64(len(c.subscribers))) } } func (c *publisherStatsCounter) AddSubscriber(id string) { c.mu.Lock() defer c.mu.Unlock() if c.subscribers[id] { return } if c.subscribers == nil { c.subscribers = make(map[string]bool) } c.subscribers[id] = true for streamType := range c.streamTypes { statsMcuSubscriberStreamTypesCurrent.WithLabelValues(streamType).Inc() } } func (c *publisherStatsCounter) RemoveSubscriber(id string) { c.mu.Lock() defer c.mu.Unlock() if !c.subscribers[id] { return } delete(c.subscribers, id) for streamType := range c.streamTypes { statsMcuSubscriberStreamTypesCurrent.WithLabelValues(streamType).Dec() } } type mcuJanusPublisher struct { mcuJanusClient id string bitrate int stats publisherStatsCounter } func (m *mcuJanus) SubscriberConnected(id string, publisher string, streamType string) { m.mu.Lock() defer m.mu.Unlock() if p, found := m.publishers[publisher+"|"+streamType]; found { p.stats.AddSubscriber(id) } } func (m *mcuJanus) SubscriberDisconnected(id string, publisher string, streamType string) { m.mu.Lock() defer m.mu.Unlock() if p, found := m.publishers[publisher+"|"+streamType]; found { p.stats.RemoveSubscriber(id) } } func min(a, b int) int { if a <= b { return a } else { return b } } func (m *mcuJanus) getOrCreatePublisherHandle(ctx context.Context, id string, streamType string, bitrate int) (*JanusHandle, uint64, uint64, error) { session := m.session if session == nil { return nil, 0, 0, ErrNotConnected } handle, err := session.Attach(ctx, pluginVideoRoom) if err != nil { return nil, 0, 0, err } log.Printf("Attached %s as publisher %d to plugin %s in session %d", streamType, handle.Id, pluginVideoRoom, session.Id) create_msg := map[string]interface{}{ "request": "create", "description": id + "|" + streamType, // We publish every stream in its own Janus room. "publishers": 1, // Do not use the video-orientation RTP extension as it breaks video // orientation changes in Firefox. "videoorient_ext": false, } var maxBitrate int if streamType == streamTypeScreen { maxBitrate = m.maxScreenBitrate } else { maxBitrate = m.maxStreamBitrate } if bitrate <= 0 { bitrate = maxBitrate } else { bitrate = min(bitrate, maxBitrate) } create_msg["bitrate"] = bitrate create_response, err := handle.Request(ctx, create_msg) if err != nil { if _, err2 := handle.Detach(ctx); err2 != nil { log.Printf("Error detaching handle %d: %s", handle.Id, err2) } return nil, 0, 0, err } roomId := getPluginIntValue(create_response.PluginData, pluginVideoRoom, "room") if roomId == 0 { if _, err := handle.Detach(ctx); err != nil { log.Printf("Error detaching handle %d: %s", handle.Id, err) } return nil, 0, 0, fmt.Errorf("No room id received: %+v", create_response) } log.Println("Created room", roomId, create_response.PluginData) msg := map[string]interface{}{ "request": "join", "ptype": "publisher", "room": roomId, "id": streamTypeUserIds[streamType], } response, err := handle.Message(ctx, msg, nil) if err != nil { if _, err2 := handle.Detach(ctx); err2 != nil { log.Printf("Error detaching handle %d: %s", handle.Id, err2) } return nil, 0, 0, err } return handle, response.Session, roomId, nil } func (m *mcuJanus) NewPublisher(ctx context.Context, listener McuListener, id string, streamType string, bitrate int, initiator McuInitiator) (McuPublisher, error) { if _, found := streamTypeUserIds[streamType]; !found { return nil, fmt.Errorf("Unsupported stream type %s", streamType) } handle, session, roomId, err := m.getOrCreatePublisherHandle(ctx, id, streamType, bitrate) if err != nil { return nil, err } client := &mcuJanusPublisher{ mcuJanusClient: mcuJanusClient{ mcu: m, listener: listener, id: atomic.AddUint64(&m.clientId, 1), session: session, roomId: roomId, streamType: streamType, handle: handle, handleId: handle.Id, closeChan: make(chan bool, 1), deferred: make(chan func(), 64), }, id: id, bitrate: bitrate, } client.mcuJanusClient.handleEvent = client.handleEvent client.mcuJanusClient.handleHangup = client.handleHangup client.mcuJanusClient.handleDetached = client.handleDetached client.mcuJanusClient.handleConnected = client.handleConnected client.mcuJanusClient.handleSlowLink = client.handleSlowLink client.mcuJanusClient.handleMedia = client.handleMedia m.registerClient(client) log.Printf("Publisher %s is using handle %d", client.id, client.handleId) go client.run(handle, client.closeChan) m.mu.Lock() m.publishers[id+"|"+streamType] = client m.publisherCreated.Notify(id + "|" + streamType) m.mu.Unlock() statsPublishersCurrent.WithLabelValues(streamType).Inc() statsPublishersTotal.WithLabelValues(streamType).Inc() return client, nil } func (p *mcuJanusPublisher) handleEvent(event *janus.EventMsg) { if videoroom := getPluginStringValue(event.Plugindata, pluginVideoRoom, "videoroom"); videoroom != "" { ctx := context.TODO() switch videoroom { case "destroyed": log.Printf("Publisher %d: associated room has been destroyed, closing", p.handleId) go p.Close(ctx) case "slow_link": // Ignore, processed through "handleSlowLink" in the general events. default: log.Printf("Unsupported videoroom publisher event in %d: %+v", p.handleId, event) } } else { log.Printf("Unsupported publisher event in %d: %+v", p.handleId, event) } } func (p *mcuJanusPublisher) handleHangup(event *janus.HangupMsg) { log.Printf("Publisher %d received hangup (%s), closing", p.handleId, event.Reason) go p.Close(context.Background()) } func (p *mcuJanusPublisher) handleDetached(event *janus.DetachedMsg) { log.Printf("Publisher %d received detached, closing", p.handleId) go p.Close(context.Background()) } func (p *mcuJanusPublisher) handleConnected(event *janus.WebRTCUpMsg) { log.Printf("Publisher %d received connected", p.handleId) p.mcu.publisherConnected.Notify(p.id + "|" + p.streamType) } func (p *mcuJanusPublisher) handleSlowLink(event *janus.SlowLinkMsg) { if event.Uplink { log.Printf("Publisher %s (%d) is reporting %d lost packets on the uplink (Janus -> client)", p.listener.PublicId(), p.handleId, event.Lost) } else { log.Printf("Publisher %s (%d) is reporting %d lost packets on the downlink (client -> Janus)", p.listener.PublicId(), p.handleId, event.Lost) } } func (p *mcuJanusPublisher) handleMedia(event *janus.MediaMsg) { mediaType := event.Type if mediaType == "video" && p.streamType == "screen" { // We want to differentiate between audio, video and screensharing mediaType = p.streamType } p.stats.EnableStream(mediaType, event.Receiving) } func (p *mcuJanusPublisher) NotifyReconnected() { ctx := context.TODO() handle, session, roomId, err := p.mcu.getOrCreatePublisherHandle(ctx, p.id, p.streamType, p.bitrate) if err != nil { log.Printf("Could not reconnect publisher %s: %s", p.id, err) // TODO(jojo): Retry return } p.handle = handle p.handleId = handle.Id p.session = session p.roomId = roomId log.Printf("Publisher %s reconnected on handle %d", p.id, p.handleId) } func (p *mcuJanusPublisher) Close(ctx context.Context) { notify := false p.mu.Lock() if handle := p.handle; handle != nil && p.roomId != 0 { destroy_msg := map[string]interface{}{ "request": "destroy", "room": p.roomId, } if _, err := handle.Request(ctx, destroy_msg); err != nil { log.Printf("Error destroying room %d: %s", p.roomId, err) } else { log.Printf("Room %d destroyed", p.roomId) } p.mcu.mu.Lock() delete(p.mcu.publishers, p.id+"|"+p.streamType) p.mcu.mu.Unlock() p.roomId = 0 notify = true } p.closeClient(ctx) p.mu.Unlock() p.stats.Reset() if notify { statsPublishersCurrent.WithLabelValues(p.streamType).Dec() p.mcu.unregisterClient(p) p.listener.PublisherClosed(p) } p.mcuJanusClient.Close(ctx) } func (p *mcuJanusPublisher) SendMessage(ctx context.Context, message *MessageClientMessage, data *MessageClientMessageData, callback func(error, map[string]interface{})) { statsMcuMessagesTotal.WithLabelValues(data.Type).Inc() jsep_msg := data.Payload switch data.Type { case "offer": p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.sendOffer(msgctx, jsep_msg, callback) } case "candidate": p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.sendCandidate(msgctx, jsep_msg["candidate"], callback) } case "endOfCandidates": // Ignore default: go callback(fmt.Errorf("Unsupported message type: %s", data.Type), nil) } } type mcuJanusSubscriber struct { mcuJanusClient publisher string } func (m *mcuJanus) getPublisher(ctx context.Context, publisher string, streamType string) (*mcuJanusPublisher, error) { // Do the direct check immediately as this should be the normal case. key := publisher + "|" + streamType m.mu.Lock() if result, found := m.publishers[key]; found { m.mu.Unlock() return result, nil } waiter := m.publisherCreated.NewWaiter(key) m.mu.Unlock() defer m.publisherCreated.Release(waiter) for { m.mu.Lock() result := m.publishers[key] m.mu.Unlock() if result != nil { return result, nil } if err := waiter.Wait(ctx); err != nil { return nil, err } } } func (m *mcuJanus) getOrCreateSubscriberHandle(ctx context.Context, publisher string, streamType string) (*JanusHandle, *mcuJanusPublisher, error) { var pub *mcuJanusPublisher var err error if pub, err = m.getPublisher(ctx, publisher, streamType); err != nil { return nil, nil, err } session := m.session if session == nil { return nil, nil, ErrNotConnected } handle, err := session.Attach(ctx, pluginVideoRoom) if err != nil { return nil, nil, err } log.Printf("Attached subscriber to room %d of publisher %s in plugin %s in session %d as %d", pub.roomId, publisher, pluginVideoRoom, session.Id, handle.Id) return handle, pub, nil } func (m *mcuJanus) NewSubscriber(ctx context.Context, listener McuListener, publisher string, streamType string) (McuSubscriber, error) { if _, found := streamTypeUserIds[streamType]; !found { return nil, fmt.Errorf("Unsupported stream type %s", streamType) } handle, pub, err := m.getOrCreateSubscriberHandle(ctx, publisher, streamType) if err != nil { return nil, err } client := &mcuJanusSubscriber{ mcuJanusClient: mcuJanusClient{ mcu: m, listener: listener, id: atomic.AddUint64(&m.clientId, 1), roomId: pub.roomId, streamType: streamType, handle: handle, handleId: handle.Id, closeChan: make(chan bool, 1), deferred: make(chan func(), 64), }, publisher: publisher, } client.mcuJanusClient.handleEvent = client.handleEvent client.mcuJanusClient.handleHangup = client.handleHangup client.mcuJanusClient.handleDetached = client.handleDetached client.mcuJanusClient.handleConnected = client.handleConnected client.mcuJanusClient.handleSlowLink = client.handleSlowLink client.mcuJanusClient.handleMedia = client.handleMedia m.registerClient(client) go client.run(handle, client.closeChan) statsSubscribersCurrent.WithLabelValues(streamType).Inc() statsSubscribersTotal.WithLabelValues(streamType).Inc() return client, nil } func (p *mcuJanusSubscriber) Publisher() string { return p.publisher } func (p *mcuJanusSubscriber) handleEvent(event *janus.EventMsg) { if videoroom := getPluginStringValue(event.Plugindata, pluginVideoRoom, "videoroom"); videoroom != "" { ctx := context.TODO() switch videoroom { case "destroyed": log.Printf("Subscriber %d: associated room has been destroyed, closing", p.handleId) go p.Close(ctx) case "event": // Ignore events like selected substream / temporal layer. case "slow_link": // Ignore, processed through "handleSlowLink" in the general events. default: log.Printf("Unsupported videoroom event %s for subscriber %d: %+v", videoroom, p.handleId, event) } } else { log.Printf("Unsupported event for subscriber %d: %+v", p.handleId, event) } } func (p *mcuJanusSubscriber) handleHangup(event *janus.HangupMsg) { log.Printf("Subscriber %d received hangup (%s), closing", p.handleId, event.Reason) go p.Close(context.Background()) } func (p *mcuJanusSubscriber) handleDetached(event *janus.DetachedMsg) { log.Printf("Subscriber %d received detached, closing", p.handleId) go p.Close(context.Background()) } func (p *mcuJanusSubscriber) handleConnected(event *janus.WebRTCUpMsg) { log.Printf("Subscriber %d received connected", p.handleId) p.mcu.SubscriberConnected(p.Id(), p.publisher, p.streamType) } func (p *mcuJanusSubscriber) handleSlowLink(event *janus.SlowLinkMsg) { if event.Uplink { log.Printf("Subscriber %s (%d) is reporting %d lost packets on the uplink (Janus -> client)", p.listener.PublicId(), p.handleId, event.Lost) } else { log.Printf("Subscriber %s (%d) is reporting %d lost packets on the downlink (client -> Janus)", p.listener.PublicId(), p.handleId, event.Lost) } } func (p *mcuJanusSubscriber) handleMedia(event *janus.MediaMsg) { // Only triggered for publishers } func (p *mcuJanusSubscriber) NotifyReconnected() { ctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() handle, pub, err := p.mcu.getOrCreateSubscriberHandle(ctx, p.publisher, p.streamType) if err != nil { // TODO(jojo): Retry? log.Printf("Could not reconnect subscriber for publisher %s: %s", p.publisher, err) p.Close(context.Background()) return } p.handle = handle p.handleId = handle.Id p.roomId = pub.roomId log.Printf("Subscriber %d for publisher %s reconnected on handle %d", p.id, p.publisher, p.handleId) } func (p *mcuJanusSubscriber) Close(ctx context.Context) { p.mu.Lock() closed := p.closeClient(ctx) p.mu.Unlock() if closed { p.mcu.SubscriberDisconnected(p.Id(), p.publisher, p.streamType) statsSubscribersCurrent.WithLabelValues(p.streamType).Dec() } p.mcu.unregisterClient(p) p.listener.SubscriberClosed(p) p.mcuJanusClient.Close(ctx) } func (p *mcuJanusSubscriber) joinRoom(ctx context.Context, callback func(error, map[string]interface{})) { handle := p.handle if handle == nil { callback(ErrNotConnected, nil) return } waiter := p.mcu.publisherConnected.NewWaiter(p.publisher + "|" + p.streamType) defer p.mcu.publisherConnected.Release(waiter) loggedNotPublishingYet := false retry: join_msg := map[string]interface{}{ "request": "join", "ptype": "subscriber", "room": p.roomId, "feed": streamTypeUserIds[p.streamType], } join_response, err := handle.Message(ctx, join_msg, nil) if err != nil { callback(err, nil) return } if error_code := getPluginIntValue(join_response.Plugindata, pluginVideoRoom, "error_code"); error_code > 0 { switch error_code { case JANUS_VIDEOROOM_ERROR_ALREADY_JOINED: // The subscriber is already connected to the room. This can happen // if a client leaves a call but keeps the subscriber objects active. // On joining the call again, the subscriber tries to join on the // MCU which will fail because he is still connected. // To get a new Offer SDP, we have to tear down the session on the // MCU and join again. p.mu.Lock() p.closeClient(ctx) p.mu.Unlock() var pub *mcuJanusPublisher handle, pub, err = p.mcu.getOrCreateSubscriberHandle(ctx, p.publisher, p.streamType) if err != nil { // Reconnection didn't work, need to unregister/remove subscriber // so a new object will be created if the request is retried. p.mcu.unregisterClient(p) p.listener.SubscriberClosed(p) callback(fmt.Errorf("Already connected as subscriber for %s, error during re-joining: %s", p.streamType, err), nil) return } p.handle = handle p.handleId = handle.Id p.roomId = pub.roomId p.closeChan = make(chan bool, 1) go p.run(p.handle, p.closeChan) log.Printf("Already connected subscriber %d for %s, leaving and re-joining on handle %d", p.id, p.streamType, p.handleId) goto retry case JANUS_VIDEOROOM_ERROR_NO_SUCH_ROOM: fallthrough case JANUS_VIDEOROOM_ERROR_NO_SUCH_FEED: switch error_code { case JANUS_VIDEOROOM_ERROR_NO_SUCH_ROOM: log.Printf("Publisher %s not created yet for %s, wait and retry to join room %d as subscriber", p.publisher, p.streamType, p.roomId) case JANUS_VIDEOROOM_ERROR_NO_SUCH_FEED: log.Printf("Publisher %s not sending yet for %s, wait and retry to join room %d as subscriber", p.publisher, p.streamType, p.roomId) } if !loggedNotPublishingYet { loggedNotPublishingYet = true statsWaitingForPublisherTotal.WithLabelValues(p.streamType).Inc() } if err := waiter.Wait(ctx); err != nil { callback(err, nil) return } log.Printf("Retry subscribing %s from %s", p.streamType, p.publisher) goto retry default: // TODO(jojo): Should we handle other errors, too? callback(fmt.Errorf("Error joining room as subscriber: %+v", join_response), nil) return } } //log.Println("Joined as listener", join_response) p.session = join_response.Session callback(nil, join_response.Jsep) } func (p *mcuJanusSubscriber) SendMessage(ctx context.Context, message *MessageClientMessage, data *MessageClientMessageData, callback func(error, map[string]interface{})) { statsMcuMessagesTotal.WithLabelValues(data.Type).Inc() jsep_msg := data.Payload switch data.Type { case "requestoffer": fallthrough case "sendoffer": p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.joinRoom(msgctx, callback) } case "answer": p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.sendAnswer(msgctx, jsep_msg, callback) } case "candidate": p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.sendCandidate(msgctx, jsep_msg["candidate"], callback) } case "endOfCandidates": // Ignore case "selectStream": substream := -1 if s, found := jsep_msg["substream"]; found { switch s := s.(type) { case int: substream = s case float32: substream = int(s) case float64: substream = int(s) default: go callback(fmt.Errorf("Unsupported substream value: %v", s), nil) return } } temporal := -1 if s, found := jsep_msg["temporal"]; found { switch s := s.(type) { case int: temporal = s case float32: temporal = int(s) case float64: temporal = int(s) default: go callback(fmt.Errorf("Unsupported temporal value: %v", s), nil) return } } if substream == -1 && temporal == -1 { // Nothing to do go callback(nil, nil) return } p.deferred <- func() { msgctx, cancel := context.WithTimeout(context.Background(), p.mcu.mcuTimeout) defer cancel() p.selectStream(msgctx, substream, temporal, callback) } default: // Return error asynchronously go callback(fmt.Errorf("Unsupported message type: %s", data.Type), nil) } }