stream-video-android-core/io.getstream.video.android.core.call/RtcSession

RtcSession

class RtcSession

The RtcSession sets up 2 peer connection

The publisher peer connection
The subscriber peer connection

It handles everything webrtc related. State is handled by the call state class

See also

CallState

Audio/video management is done by the MediaManager

MediaManagerImpl

This is how the offer/answer cycle works

sessionId is created locally as a random UUID
create the peer connections
capture audio and video (if we're not doing so already, in many apps it should already be on for the preview screen)
execute the join request
add the audio/video tracks which triggers onNegotiationNeeded
onNegotiationNeeded(which calls SetPublisherRequest)
JoinCallResponseEvent returns info on the call's state

Dynascale automatically negotiates resolutions across clients

We send what resolutions we want using UpdateSubscriptionsRequest.
It should be triggered as we paginate through participants
Or when the UI layout changes
The SFU tells us what resolution to publish using the ChangePublishQualityEvent event

Properties

val sfuSocketState: StateFlow<SfuSocketState>

var subscriber: StreamPeerConnection?

subscriber peer connection is used for subs

trackDimensions

val trackDimensions: MutableStateFlow<Map<String, Map<<Error class: unknown class>, TrackDimensions>>>

trackDimensionsDebounced

val trackDimensionsDebounced: Flow<Map<String, Map<<Error class: unknown class>, TrackDimensions>>>

var tracks: MutableMap<String, MutableMap<<Error class: unknown class>, MediaTrack>>

Functions

suspend fun connect(reconnectDetails: <Error class: unknown class>? = null)

createPublisher

@VisibleForTesting

fun createPublisher(): StreamPeerConnection

createSubscriber

@VisibleForTesting

fun createSubscriber(): StreamPeerConnection

getPublisherStats

suspend fun getPublisherStats(): RtcStatsReport?

getSubscriberStats

suspend fun getSubscriberStats(): RtcStatsReport?

fun handleEvent(event: VideoEvent)

handleIceTrickle

@VisibleForTesting

suspend fun handleIceTrickle(event: ICETrickleEvent)

Triggered whenever we receive new ice candidate from the SFU

handleSubscriberOffer

@VisibleForTesting

suspend fun handleSubscriberOffer(offerEvent: SubscriberOfferEvent)

This is called when the SFU sends us an offer

onNegotiationNeeded

@VisibleForTesting

fun onNegotiationNeeded(peerConnection: StreamPeerConnection, peerType: StreamPeerType)

https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/negotiationneeded_event

suspend fun reconnect(forceRestart: Boolean)

requestPublisherIceRestart

suspend fun requestPublisherIceRestart(): Result<<Error class: unknown class>>

requestSubscriberIceRestart

suspend fun requestSubscriberIceRestart(): Result<<Error class: unknown class>>

setScreenShareTrack

fun setScreenShareTrack()

updateTrackDimensions

fun updateTrackDimensions(sessionId: String, trackType: <Error class: unknown class>, visible: Boolean, dimensions: <Error class: unknown class> = defaultVideoDimension)