lksdk

package module
Version: v0.7.2 Latest Latest
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Published: Oct 8, 2021 License: Apache-2.0 Imports: 37 Imported by: 2

README

LiveKit Go SDK

This is the official Golang SDK to LiveKit. You would integrate this on your app's backend in order to

  • Create access tokens
  • Access LiveKit server-side APIs, giving you moderation capabilities
  • Client SDK to interact as participant, publish & record room streams
  • Receive webhook callbacks

Token creation

import (
	"time"

	lksdk "github.com/livekit/server-sdk-go"
	"github.com/livekit/protocol/auth"
)

func getJoinToken(apiKey, apiSecret, room, identity string) (string, error) {
	at := auth.NewAccessToken(apiKey, apiSecret)
	grant := &auth.VideoGrant{
		RoomJoin: true,
		Room:     room,
	}
	at.AddGrant(grant).
		SetIdentity(identity).
		SetValidFor(time.Hour)

	return at.ToJWT()
}

RoomService API

RoomService gives you complete control over rooms and participants within them. It includes selective track subscriptions as well as moderation capabilities.

import (
	lksdk "github.com/livekit/server-sdk-go"
	livekit "github.com/livekit/protocol/proto"
)

func main() {
	host := "host"
	apiKey := "key"
	apiSecret := "secret"

	roomName := "myroom"
	identity := "participantIdentity"

    roomClient := lksdk.NewRoomServiceClient(host, apiKey, apiSecret)

    // create a new room
    room, _ := roomClient.CreateRoom(context.Background(), &livekit.CreateRoomRequest{
		Name: roomName,
	})

    // list rooms
    res, _ := roomClient.ListRooms(context.Background(), &livekit.ListRoomsRequest{})

    // terminate a room and cause participants to leave
    roomClient.DeleteRoom(context.Background(), &livekit.DeleteRoomRequest{
		Room: roomId,
	})

    // list participants in a room
    res, _ := roomClient.ListParticipants(context.Background(), &livekit.ListParticipantsRequest{
		Room: roomName,
	})

    // disconnect a participant from room
    roomClient.RemoveParticipant(context.Background(), &livekit.RoomParticipantIdentity{
		Room:     roomName,
		Identity: identity,
	})

    // mute/unmute participant's tracks
    roomClient.MutePublishedTrack(context.Background(), &livekit.MuteRoomTrackRequest{
		Room:     roomName,
		Identity: identity,
		TrackSid: "track_sid",
		Muted:    true,
	})
}

Interacting as a participant

The Participant SDK gives you access programmatic access as a client enabling you to publish and record audio/video/data to the room.

import (
  lksdk "github.com/livekit/server-sdk-go"
)

func main() {
  host := "<host>"
  apiKey := "api-key"
  apiSecret := "api-secret"
  roomName := "myroom"
  identity := "botuser"
	room, err := lksdk.ConnectToRoom(host, lksdk.ConnectInfo{
		APIKey:              apiKey,
		APISecret:           apiSecret,
		RoomName:            roomName,
		ParticipantIdentity: identity,
	})
	if err != nil {
		panic(err)
	}

  room.Callback.OnTrackSubscribed = trackSubscribed
  ...
  room.Disconnect()
}

func trackSubscribed(track *webrtc.TrackRemote, publication lksdk.TrackPublication, rp *lksdk.RemoteParticipant) {

}

Publishing tracks to Room

With the Go SDK, you can publish existing files encoded in H.264, VP8, and Opus to the room.

First, you will need to encode media into the right format.

VP8 / Opus
INPUT_FILE=<file> \
OUTPUT_VP8=<output.ivf> \
OUTPUT_OGG=<output.ogg> \
ffmpeg -i $INPUT_FILE \
  -c:v libvpx -keyint_min 120 -qmax 50 -maxrate 2M -b:v 1M $OUTPUT_VP8 \
  -c:a libopus -page_duration 20000 -vn $OUTPUT_OGG

The above encodes VP8 at average 1Mbps / max 2Mbps with a minimum keyframe interval of 120.

H.264 / Opus
INPUT_FILE=<file> \
OUTPUT_H264=<output.h264> \
OUTPUT_OGG=<output.ogg> \
ffmpeg -i $INPUT_FILE
  -c:v libx264 -bsf:v h264_mp4toannexb -b:v 2M -x264-params keyint=120 -max_delay 0 -bf 0 $OUTPUT_H264 \
  -c:a libopus -page_duration 20000 -vn $OUTPUT_OGG

The above encodes H264 with CBS of 2Mbps with a minimum keyframe interval of 120.

Publish from file
file := "video.ivf"
track, err := lksdk.NewLocalFileTrack(file,
	// control FPS to ensure synchronization
	lksdk.FileTrackWithFrameDuration(33 * time.Millisecond),
	lksdk.FileTrackWithOnWriteComplete(func() { fmt.Println("track finished") }),
)
if err != nil {
    return err
}
if _, err = room.LocalParticipant.PublishTrack(track, file); err != nil {
    return err
}

For a full working example, refer to join.go in livekit-cli.

Publish from other sources

In order to publish from non-file sources, you will have to implement your own SampleProvider, that could provide frames of data with a NextSample method.

The SDK takes care of sending the samples to the room.

Receiving webhooks

The Go SDK helps you to verify and decode webhook callbacks to ensure their authenticity. See webhooks guide for configuration.

import (
	livekit "github.com/livekit/protocol/proto"
	"github.com/livekit/protocol/webhook"
	"google.golang.org/protobuf/encoding/protojson"
)

func ServeHTTP(w http.ResponseWriter, r *http.Request) {
	data, err := webhook.Receive(r, s.provider)
	if err != nil {
		// could not validate, handle error
		return
	}

	event := livekit.WebhookEvent{}
	if err = protojson.Unmarshal(data, &event); err != nil {
		// handle error
		return
	}

	// consume WebhookEvent
}

Documentation

Index

Constants

View Source
const PROTOCOL = 3
View Source
const Version = "0.6.4"

Variables

View Source
var (
	ErrConnectionTimeout   = errors.New("could not connect after timeout")
	ErrTrackPublishTimeout = errors.New("timed out publishing track")
	ErrCannotDetermineMime = errors.New("cannot determine mimetype from file extension")
	ErrUnsupportedFileType = errors.New("FileSampleProvider does not support this mime type")
)

Functions

func FileTrackWithFrameDuration added in v0.7.0

func FileTrackWithFrameDuration(duration time.Duration) func(provider *FileSampleProvider)

func FileTrackWithMime added in v0.7.0

func FileTrackWithMime(mime string) func(provider *FileSampleProvider)

func FileTrackWithOnWriteComplete added in v0.7.0

func FileTrackWithOnWriteComplete(f func()) func(provider *FileSampleProvider)

func FromProtoIceServers

func FromProtoIceServers(iceservers []*livekit.ICEServer) []webrtc.ICEServer

func FromProtoTrickle

func FromProtoTrickle(trickle *livekit.TrickleRequest) webrtc.ICECandidateInit

func SetLogger

func SetLogger(l logr.Logger)

SetLogger overrides logger with a logr implementation https://github.com/go-logr/logr

func ToProtoTrickle

func ToProtoTrickle(candidateInit webrtc.ICECandidateInit, target livekit.SignalTarget) *livekit.TrickleRequest

Types

type AudioSampleProvider added in v0.7.0

type AudioSampleProvider interface {
	SampleProvider
	CurrentAudioLevel() uint8
}

type ConnectInfo

type ConnectInfo struct {
	APIKey              string
	APISecret           string
	RoomName            string
	ParticipantIdentity string
	ParticipantMetadata string
}

type ConnectOption added in v0.6.1

type ConnectOption func(*ConnectParams)

func WithAutoSubscribe added in v0.6.1

func WithAutoSubscribe(val bool) ConnectOption

type ConnectParams added in v0.6.1

type ConnectParams struct {
	AutoSubscribe bool
}

type FileSampleProvider added in v0.7.0

type FileSampleProvider struct {
	Mime            string
	FileName        string
	FrameDuration   time.Duration
	OnWriteComplete func()
	AudioLevel      uint8
	// contains filtered or unexported fields
}

FileSampleProvider provides samples by reading from a video file

func (*FileSampleProvider) CurrentAudioLevel added in v0.7.0

func (p *FileSampleProvider) CurrentAudioLevel() uint8

func (*FileSampleProvider) NextSample added in v0.7.0

func (p *FileSampleProvider) NextSample() (media.Sample, error)

func (*FileSampleProvider) OnBind added in v0.7.0

func (p *FileSampleProvider) OnBind() error

func (*FileSampleProvider) OnUnbind added in v0.7.0

func (p *FileSampleProvider) OnUnbind() error

type FileSampleProviderOption added in v0.7.0

type FileSampleProviderOption func(*FileSampleProvider)

type LoadTestProvider

type LoadTestProvider struct {
	BytesPerSample uint32
	SampleDuration time.Duration
}

LoadTestProvider is designed to be used with the load tester. It provides samples that are encoded with sequence and timing information, in order determine RTT and loss

func NewLoadTestProvider

func NewLoadTestProvider(bitrate uint32) (*LoadTestProvider, error)

func (*LoadTestProvider) NextSample

func (p *LoadTestProvider) NextSample() (media.Sample, error)

func (*LoadTestProvider) OnBind added in v0.7.0

func (p *LoadTestProvider) OnBind() error

func (*LoadTestProvider) OnUnbind added in v0.7.0

func (p *LoadTestProvider) OnUnbind() error

type LocalParticipant

type LocalParticipant struct {
	// contains filtered or unexported fields
}

func (*LocalParticipant) AudioLevel

func (p *LocalParticipant) AudioLevel() float32

func (*LocalParticipant) Identity

func (p *LocalParticipant) Identity() string

func (*LocalParticipant) IsSpeaking

func (p *LocalParticipant) IsSpeaking() bool

func (*LocalParticipant) Metadata added in v0.5.13

func (p *LocalParticipant) Metadata() string

func (*LocalParticipant) PublishData added in v0.5.12

func (p *LocalParticipant) PublishData(data []byte, kind livekit.DataPacket_Kind, destinationSids []string) error

func (*LocalParticipant) PublishTrack

func (p *LocalParticipant) PublishTrack(track webrtc.TrackLocal, name string) (*LocalTrackPublication, error)

func (*LocalParticipant) SID

func (p *LocalParticipant) SID() string

func (*LocalParticipant) Tracks

func (p *LocalParticipant) Tracks() []TrackPublication

func (*LocalParticipant) UnpublishTrack added in v0.7.0

func (p *LocalParticipant) UnpublishTrack(sid string) error

type LocalSampleTrack

type LocalSampleTrack struct {
	// contains filtered or unexported fields
}

LocalSampleTrack is a local track that simplifies writing samples. It handles timing and publishing of things, so as long as a SampleProvider is provided, the class takes care of publishing tracks at the right frequency This extends webrtc.TrackLocalStaticSample, and adds the ability to write RTP extensions

func NewLocalFileTrack added in v0.7.0

func NewLocalFileTrack(file string, options ...FileSampleProviderOption) (*LocalSampleTrack, error)

func NewLocalSampleTrack

func NewLocalSampleTrack(c webrtc.RTPCodecCapability) (*LocalSampleTrack, error)

func (*LocalSampleTrack) Bind

Bind is an interface for TrackLocal, not for external consumption

func (*LocalSampleTrack) Codec added in v0.7.0

Codec gets the Codec of the track

func (*LocalSampleTrack) ID added in v0.7.0

func (s *LocalSampleTrack) ID() string

ID is the unique identifier for this Track. This should be unique for the stream, but doesn't have to globally unique. A common example would be 'audio' or 'video' and StreamID would be 'desktop' or 'webcam'

func (*LocalSampleTrack) IsBound added in v0.7.0

func (s *LocalSampleTrack) IsBound() bool

func (*LocalSampleTrack) Kind added in v0.7.0

Kind controls if this TrackLocal is audio or video

func (*LocalSampleTrack) OnBind added in v0.7.0

func (s *LocalSampleTrack) OnBind(f func())

OnBind sets a callback to be called when the track has been negotiated for publishing and bound to a peer connection

func (*LocalSampleTrack) OnUnbind added in v0.7.0

func (s *LocalSampleTrack) OnUnbind(f func())

OnUnbind sets a callback to be called after the track is removed from a peer connection

func (*LocalSampleTrack) StartWrite added in v0.7.0

func (s *LocalSampleTrack) StartWrite(provider SampleProvider, onComplete func()) error

func (*LocalSampleTrack) StreamID added in v0.7.0

func (s *LocalSampleTrack) StreamID() string

StreamID is the group this track belongs too. This must be unique

func (*LocalSampleTrack) Unbind

Unbind is an interface for TrackLocal, not for external consumption

func (*LocalSampleTrack) WriteSample added in v0.7.0

func (s *LocalSampleTrack) WriteSample(sample media.Sample, opts *SampleWriteOptions) error

type LocalTrackPublication

type LocalTrackPublication struct {
	// contains filtered or unexported fields
}

func (*LocalTrackPublication) IsMuted

func (p *LocalTrackPublication) IsMuted() bool

func (*LocalTrackPublication) IsSubscribed

func (p *LocalTrackPublication) IsSubscribed() bool

func (*LocalTrackPublication) Kind

func (p *LocalTrackPublication) Kind() TrackKind

func (*LocalTrackPublication) Name

func (p *LocalTrackPublication) Name() string

func (*LocalTrackPublication) SID

func (p *LocalTrackPublication) SID() string

func (*LocalTrackPublication) SetMuted

func (p *LocalTrackPublication) SetMuted(muted bool)

func (*LocalTrackPublication) Track

func (p *LocalTrackPublication) Track() Track

func (*LocalTrackPublication) TrackLocal

func (p *LocalTrackPublication) TrackLocal() webrtc.TrackLocal

type NullSampleProvider

type NullSampleProvider struct {
	BytesPerSample uint32
	SampleDuration time.Duration
}

NullSampleProvider is a media provider that provides null packets, it could meet a certain bitrate, if desired

func NewNullSampleProvider

func NewNullSampleProvider(bitrate uint32) *NullSampleProvider

func (*NullSampleProvider) NextSample

func (p *NullSampleProvider) NextSample() (media.Sample, error)

func (*NullSampleProvider) OnBind added in v0.7.0

func (p *NullSampleProvider) OnBind() error

func (*NullSampleProvider) OnUnbind added in v0.7.0

func (p *NullSampleProvider) OnUnbind() error

type PCTransport

type PCTransport struct {
	OnOffer func(description webrtc.SessionDescription)
	// contains filtered or unexported fields
}

PCTransport is a wrapper around PeerConnection, with some helper methods

func NewPCTransport

func NewPCTransport(iceServers []webrtc.ICEServer) (*PCTransport, error)

func (*PCTransport) AddICECandidate

func (t *PCTransport) AddICECandidate(candidate webrtc.ICECandidateInit) error

func (*PCTransport) Close

func (t *PCTransport) Close() error

func (*PCTransport) IsConnected

func (t *PCTransport) IsConnected() bool

func (*PCTransport) Negotiate added in v0.7.0

func (t *PCTransport) Negotiate()

func (*PCTransport) PeerConnection

func (t *PCTransport) PeerConnection() *webrtc.PeerConnection

func (*PCTransport) SetRemoteDescription

func (t *PCTransport) SetRemoteDescription(sd webrtc.SessionDescription) error

type Participant

type Participant interface {
	SID() string
	Identity() string
	IsSpeaking() bool
	AudioLevel() float32

	Tracks() []TrackPublication
	Metadata() string
	// contains filtered or unexported methods
}

type ParticipantCallback

type ParticipantCallback struct {
	// for all participants
	OnTrackMuted        func(pub TrackPublication, p Participant)
	OnTrackUnmuted      func(pub TrackPublication, p Participant)
	OnMetadataChanged   func(oldMetadata string, p Participant)
	OnIsSpeakingChanged func(p Participant)

	// for remote participants
	OnTrackSubscribed         func(track *webrtc.TrackRemote, publication TrackPublication, rp *RemoteParticipant)
	OnTrackUnsubscribed       func(track *webrtc.TrackRemote, publication TrackPublication, rp *RemoteParticipant)
	OnTrackSubscriptionFailed func(sid string, rp *RemoteParticipant)
	OnTrackPublished          func(publication TrackPublication, rp *RemoteParticipant)
	OnTrackUnpublished        func(publication TrackPublication, rp *RemoteParticipant)
	OnDataReceived            func(data []byte, rp *RemoteParticipant)
}

func NewParticipantCallback

func NewParticipantCallback() *ParticipantCallback

type PubCallback

type PubCallback func(pub TrackPublication, participant *RemoteParticipant)

type RTCEngine

type RTCEngine struct {
	JoinTimeout time.Duration

	// callbacks
	OnDisconnected          func()
	OnMediaTrack            func(track *webrtc.TrackRemote, receiver *webrtc.RTPReceiver)
	OnParticipantUpdate     func([]*livekit.ParticipantInfo)
	OnActiveSpeakersChanged func([]*livekit.SpeakerInfo)
	OnSpeakersChanged       func([]*livekit.SpeakerInfo)
	OnDataReceived          func(userPacket *livekit.UserPacket)
	// contains filtered or unexported fields
}

func NewRTCEngine

func NewRTCEngine() *RTCEngine

func (*RTCEngine) Close

func (e *RTCEngine) Close()

func (*RTCEngine) IsConnected

func (e *RTCEngine) IsConnected() bool

func (*RTCEngine) Join

func (e *RTCEngine) Join(url string, token string, params *ConnectParams) (*livekit.JoinResponse, error)

func (*RTCEngine) TrackPublishedChan

func (e *RTCEngine) TrackPublishedChan() <-chan *livekit.TrackPublishedResponse

type RecordingServiceClient added in v0.6.1

type RecordingServiceClient struct {
	livekit.RecordingService
	// contains filtered or unexported fields
}

func NewRecordingServiceClient added in v0.6.1

func NewRecordingServiceClient(url string, apiKey string, secretKey string) *RecordingServiceClient

func (*RecordingServiceClient) AddOutput added in v0.7.2

func (*RecordingServiceClient) EndRecording added in v0.6.1

func (*RecordingServiceClient) RemoveOutput added in v0.7.2

func (*RecordingServiceClient) StartRecording added in v0.6.1

type RemoteParticipant

type RemoteParticipant struct {
	// contains filtered or unexported fields
}

func (*RemoteParticipant) AudioLevel

func (p *RemoteParticipant) AudioLevel() float32

func (*RemoteParticipant) Identity

func (p *RemoteParticipant) Identity() string

func (*RemoteParticipant) IsSpeaking

func (p *RemoteParticipant) IsSpeaking() bool

func (*RemoteParticipant) Metadata added in v0.5.13

func (p *RemoteParticipant) Metadata() string

func (*RemoteParticipant) SID

func (p *RemoteParticipant) SID() string

func (*RemoteParticipant) Tracks

func (p *RemoteParticipant) Tracks() []TrackPublication

type RemoteTrackPublication

type RemoteTrackPublication struct {
	// contains filtered or unexported fields
}

func (*RemoteTrackPublication) IsMuted

func (p *RemoteTrackPublication) IsMuted() bool

func (*RemoteTrackPublication) IsSubscribed

func (p *RemoteTrackPublication) IsSubscribed() bool

func (*RemoteTrackPublication) Kind

func (p *RemoteTrackPublication) Kind() TrackKind

func (*RemoteTrackPublication) Name

func (p *RemoteTrackPublication) Name() string

func (*RemoteTrackPublication) Receiver

func (p *RemoteTrackPublication) Receiver() *webrtc.RTPReceiver

func (*RemoteTrackPublication) SID

func (p *RemoteTrackPublication) SID() string

func (*RemoteTrackPublication) Track

func (p *RemoteTrackPublication) Track() Track

func (*RemoteTrackPublication) TrackRemote

func (p *RemoteTrackPublication) TrackRemote() *webrtc.TrackRemote

type Room

type Room struct {
	SID              string
	Name             string
	LocalParticipant *LocalParticipant

	ActiveSpeakers []Participant
	Callback       *RoomCallback
	// contains filtered or unexported fields
}

func ConnectToRoom

func ConnectToRoom(url string, info ConnectInfo, opts ...ConnectOption) (*Room, error)

func ConnectToRoomWithToken

func ConnectToRoomWithToken(url, token string, opts ...ConnectOption) (*Room, error)

func (*Room) Disconnect

func (r *Room) Disconnect()

func (*Room) GetParticipant

func (r *Room) GetParticipant(sid string) *RemoteParticipant

func (*Room) GetParticipants

func (r *Room) GetParticipants() []*RemoteParticipant

type RoomCallback

type RoomCallback struct {
	OnDisconnected            func()
	OnParticipantConnected    func(*RemoteParticipant)
	OnParticipantDisconnected func(*RemoteParticipant)
	OnActiveSpeakersChanged   func([]Participant)

	ParticipantCallback
}

func NewRoomCallback

func NewRoomCallback() *RoomCallback

type RoomServiceClient

type RoomServiceClient struct {
	livekit.RoomService
	// contains filtered or unexported fields
}

func NewRoomServiceClient

func NewRoomServiceClient(url string, apiKey string, secretKey string) *RoomServiceClient

func (*RoomServiceClient) CreateRoom

func (*RoomServiceClient) CreateToken

func (c *RoomServiceClient) CreateToken() *auth.AccessToken

func (*RoomServiceClient) DeleteRoom

func (*RoomServiceClient) GetParticipant

func (*RoomServiceClient) ListParticipants

func (*RoomServiceClient) ListRooms

func (*RoomServiceClient) MutePublishedTrack

func (*RoomServiceClient) RemoveParticipant

func (*RoomServiceClient) SendData added in v0.7.1

func (*RoomServiceClient) UpdateParticipant

type SampleProvider

type SampleProvider interface {
	NextSample() (media.Sample, error)
	OnBind() error
	OnUnbind() error
}

type SampleWriteOptions added in v0.7.0

type SampleWriteOptions struct {
	AudioLevel *uint8
}

type SignalClient

type SignalClient struct {
	OnClose               func()
	OnAnswer              func(sd webrtc.SessionDescription)
	OnOffer               func(sd webrtc.SessionDescription)
	OnTrickle             func(init webrtc.ICECandidateInit, target livekit.SignalTarget)
	OnParticipantUpdate   func([]*livekit.ParticipantInfo)
	OnLocalTrackPublished func(response *livekit.TrackPublishedResponse)
	OnSpeakersChanged     func([]*livekit.SpeakerInfo)
	OnLeave               func()
	// contains filtered or unexported fields
}

func NewSignalClient

func NewSignalClient() *SignalClient

func (*SignalClient) Close

func (c *SignalClient) Close()

func (*SignalClient) IsConnected

func (c *SignalClient) IsConnected() bool

func (*SignalClient) Join

func (c *SignalClient) Join(urlPrefix string, token string, params *ConnectParams) (*livekit.JoinResponse, error)

func (*SignalClient) ReadResponse

func (c *SignalClient) ReadResponse() (*livekit.SignalResponse, error)

func (*SignalClient) SendAnswer

func (c *SignalClient) SendAnswer(sd webrtc.SessionDescription) error

func (*SignalClient) SendICECandidate

func (c *SignalClient) SendICECandidate(candidate webrtc.ICECandidateInit, target livekit.SignalTarget) error

func (*SignalClient) SendLeave

func (c *SignalClient) SendLeave() error

func (*SignalClient) SendMuteTrack

func (c *SignalClient) SendMuteTrack(sid string, muted bool) error

func (*SignalClient) SendOffer

func (c *SignalClient) SendOffer(sd webrtc.SessionDescription) error

func (*SignalClient) SendRequest

func (c *SignalClient) SendRequest(req *livekit.SignalRequest) error

type Track

type Track interface {
	ID() string
}

type TrackKind

type TrackKind string
const (
	TrackKindVideo TrackKind = "video"
	TrackKindAudio TrackKind = "audio"
)

func KindFromRTPType

func KindFromRTPType(rt webrtc.RTPCodecType) TrackKind

func (TrackKind) ProtoType

func (k TrackKind) ProtoType() livekit.TrackType

func (TrackKind) RTPType

func (k TrackKind) RTPType() webrtc.RTPCodecType

func (TrackKind) String

func (k TrackKind) String() string

type TrackPubCallback

type TrackPubCallback func(track Track, pub TrackPublication, participant *RemoteParticipant)

type TrackPublication

type TrackPublication interface {
	Name() string
	SID() string
	Kind() TrackKind
	IsMuted() bool
	IsSubscribed() bool
	// Track is either a webrtc.TrackLocal or webrtc.TrackRemote
	Track() Track
	// contains filtered or unexported methods
}

type TrackPublicationOptions

type TrackPublicationOptions struct {
	Name string
}

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