Files
webrtc/examples/data-channels/main.go
backkem 0043a4bf9a DataChannels: OpenChannel & OnOpen
- OpenChannel messages are now sent after SCTP is Established.
- The OnOpen handler tells the application when a channel has opened.

Relates to #159
2018-09-25 13:07:39 -07:00

127 lines
3.1 KiB
Go

package main
import (
"bufio"
"encoding/base64"
"fmt"
"io"
"math/rand"
"os"
"time"
"github.com/pions/webrtc"
"github.com/pions/webrtc/pkg/datachannel"
"github.com/pions/webrtc/pkg/ice"
)
func main() {
// Wait for the offer to be pasted
sd := mustReadStdin()
/* Everything below is the pion-WebRTC API, thanks for using it! */
// Prepare the configuration
config := webrtc.RTCConfiguration{
IceServers: []webrtc.RTCIceServer{
{
URLs: []string{"stun:stun.l.google.com:19302"},
},
},
}
// Create a new RTCPeerConnection
peerConnection, err := webrtc.New(config)
check(err)
// Set the handler for ICE connection state
// This will notify you when the peer has connected/disconnected
peerConnection.OnICEConnectionStateChange = func(connectionState ice.ConnectionState) {
fmt.Printf("ICE Connection State has changed: %s\n", connectionState.String())
}
// Register data channel creation handling
peerConnection.OnDataChannel = func(d *webrtc.RTCDataChannel) {
fmt.Printf("New DataChannel %s %d\n", d.Label, d.ID)
d.Lock()
defer d.Unlock()
// Register channel opening handling
d.OnOpen = func() {
fmt.Printf("Data channel '%s'-'%d' open. Random messages will now be sent to any connected DataChannels every 5 seconds\n", d.Label, d.ID)
for {
time.Sleep(5 * time.Second)
message := randSeq(15)
fmt.Printf("Sending %s \n", message)
err := d.Send(datachannel.PayloadString{Data: []byte(message)})
check(err)
}
}
// Register message handling
d.Onmessage = func(payload datachannel.Payload) {
switch p := payload.(type) {
case *datachannel.PayloadString:
fmt.Printf("Message '%s' from DataChannel '%s' payload '%s'\n", p.PayloadType().String(), d.Label, string(p.Data))
case *datachannel.PayloadBinary:
fmt.Printf("Message '%s' from DataChannel '%s' payload '% 02x'\n", p.PayloadType().String(), d.Label, p.Data)
default:
fmt.Printf("Message '%s' from DataChannel '%s' no payload \n", p.PayloadType().String(), d.Label)
}
}
}
// Set the remote SessionDescription
offer := webrtc.RTCSessionDescription{
Type: webrtc.RTCSdpTypeOffer,
Sdp: string(sd),
}
err = peerConnection.SetRemoteDescription(offer)
check(err)
// Sets the LocalDescription, and starts our UDP listeners
answer, err := peerConnection.CreateAnswer(nil)
check(err)
// Get the LocalDescription and take it to base64 so we can paste in browser
fmt.Println(base64.StdEncoding.EncodeToString([]byte(answer.Sdp)))
// Block forever
select {}
}
func randSeq(n int) string {
r := rand.New(rand.NewSource(time.Now().UnixNano()))
letters := []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
b := make([]rune, n)
for i := range b {
b[i] = letters[r.Intn(len(letters))]
}
return string(b)
}
// mustReadStdin blocks untill input is received from stdin
func mustReadStdin() string {
reader := bufio.NewReader(os.Stdin)
rawSd, err := reader.ReadString('\n')
if err != io.EOF {
check(err)
}
fmt.Println("")
sd, err := base64.StdEncoding.DecodeString(rawSd)
check(err)
return string(sd)
}
// check is used to panic in an error occurs.
func check(err error) {
if err != nil {
panic(err)
}
}