Examples: Make examples/util internal

Resolves #424

examples/data-channels/main.go

@@ -5,8 +5,9 @@ import (
 	"time"
 
 	"github.com/pions/webrtc"
-	"github.com/pions/webrtc/examples/util"
-	"github.com/pions/webrtc/pkg/datachannel"
+	sugar "github.com/pions/webrtc/pkg/datachannel"
+
+	"github.com/pions/webrtc/examples/internal/signal"
 )
 
 func main() {
@@ -23,7 +24,9 @@ func main() {
 
 	// Create a new RTCPeerConnection
 	peerConnection, err := webrtc.NewPeerConnection(config)
-	util.Check(err)
+	if err != nil {
+		panic(err)
+	}
 
 	// Set the handler for ICE connection state
 	// This will notify you when the peer has connected/disconnected
@@ -40,20 +43,22 @@ func main() {
 			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 range time.NewTicker(5 * time.Second).C {
-				message := util.RandSeq(15)
+				message := signal.RandSeq(15)
 				fmt.Printf("Sending %s \n", message)
 
-				err := d.Send(datachannel.PayloadString{Data: []byte(message)})
-				util.Check(err)
+				err := d.Send(sugar.PayloadString{Data: []byte(message)})
+				if err != nil {
+					panic(err)
+				}
 			}
 		})
 
 		// Register message handling
-		d.OnMessage(func(payload datachannel.Payload) {
+		d.OnMessage(func(payload sugar.Payload) {
 			switch p := payload.(type) {
-			case *datachannel.PayloadString:
+			case *sugar.PayloadString:
 				fmt.Printf("Message '%s' from DataChannel '%s' payload '%s'\n", p.PayloadType().String(), d.Label, string(p.Data))
-			case *datachannel.PayloadBinary:
+			case *sugar.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)
@@ -63,22 +68,28 @@ func main() {
 
 	// Wait for the offer to be pasted
 	offer := webrtc.SessionDescription{}
-	util.Decode(util.MustReadStdin(), &offer)
+	signal.Decode(signal.MustReadStdin(), &offer)
 
 	// Set the remote SessionDescription
 	err = peerConnection.SetRemoteDescription(offer)
-	util.Check(err)
+	if err != nil {
+		panic(err)
+	}
 
 	// Create an answer
 	answer, err := peerConnection.CreateAnswer(nil)
-	util.Check(err)
+	if err != nil {
+		panic(err)
+	}
 
 	// Sets the LocalDescription, and starts our UDP listeners
 	err = peerConnection.SetLocalDescription(answer)
-	util.Check(err)
+	if err != nil {
+		panic(err)
+	}
 
 	// Output the answer in base64 so we can paste it in browser
-	fmt.Println(util.Encode(answer))
+	fmt.Println(signal.Encode(answer))
 
 	// Block forever
 	select {}