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client multiplexes AND recovers correctly! (close #31)

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- stabilize rest of WebRTCPeer
 - use uid for the datachannel label
 - store a consistent WebRTC config in the dialer
This commit is contained in:
Serene Han 2016-06-15 18:59:55 -07:00
parent 2bf0e5457e
commit e93c38f834
8 changed files with 50 additions and 35 deletions
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40
client/webrtc.go
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@ -3,16 +3,22 @@ package main
import (
"bytes"
"errors"
"github.com/keroserene/go-webrtc"
"io"
"log"
"time"
"github.com/dchest/uniuri"
"github.com/keroserene/go-webrtc"
)
// Remote WebRTC peer.
// Implements the |Snowflake| interface, which includes
// |io.ReadWriter|, |Resetter|, and |Connector|.
type webRTCConn struct {
//
// Handles preparation of go-webrtc PeerConnection. Only ever has
// one DataChannel.
type WebRTCPeer struct {
id string
config *webrtc.Configuration
pc *webrtc.PeerConnection
transport SnowflakeDataChannel // Holds the WebRTC DataChannel.
@ -33,13 +39,13 @@ type webRTCConn struct {
// Read bytes from local SOCKS.
// As part of |io.ReadWriter|
func (c *webRTCConn) Read(b []byte) (int, error) {
func (c *WebRTCPeer) Read(b []byte) (int, error) {
return c.recvPipe.Read(b)
}
// Writes bytes out to remote WebRTC.
// As part of |io.ReadWriter|
func (c *webRTCConn) Write(b []byte) (int, error) {
func (c *WebRTCPeer) Write(b []byte) (int, error) {
c.BytesLogger.AddOutbound(len(b))
if nil == c.transport {
log.Printf("Buffered %d bytes --> WebRTC", len(b))
@ -51,7 +57,7 @@ func (c *webRTCConn) Write(b []byte) (int, error) {
}
// As part of |Snowflake|
func (c *webRTCConn) Close() error {
func (c *WebRTCPeer) Close() error {
var err error = nil
log.Printf("WebRTC: Closing")
c.cleanup()
@ -61,7 +67,7 @@ func (c *webRTCConn) Close() error {
}
// As part of |Resetter|
func (c *webRTCConn) Reset() {
func (c *WebRTCPeer) Reset() {
c.Close()
go func() {
c.reset <- struct{}{}
@ -70,12 +76,13 @@ func (c *webRTCConn) Reset() {
}
// As part of |Resetter|
func (c *webRTCConn) WaitForReset() { <-c.reset }
func (c *WebRTCPeer) WaitForReset() { <-c.reset }
// Construct a WebRTC PeerConnection.
func NewWebRTCConnection(config *webrtc.Configuration,
broker *BrokerChannel) *webRTCConn {
connection := new(webRTCConn)
broker *BrokerChannel) *WebRTCPeer {
connection := new(WebRTCPeer)
connection.id = "snowflake-" + uniuri.New()
connection.config = config
connection.broker = broker
connection.offerChannel = make(chan *webrtc.SessionDescription, 1)
@ -94,7 +101,8 @@ func NewWebRTCConnection(config *webrtc.Configuration,
}
// As part of |Connector| interface.
func (c *webRTCConn) Connect() error {
func (c *WebRTCPeer) Connect() error {
log.Println(c.id, " connecting...")
// TODO: When go-webrtc is more stable, it's possible that a new
// PeerConnection won't need to be re-prepared each time.
err := c.preparePeerConnection()
@ -113,7 +121,7 @@ func (c *webRTCConn) Connect() error {
}
// Create and prepare callbacks on a new WebRTC PeerConnection.
func (c *webRTCConn) preparePeerConnection() error {
func (c *WebRTCPeer) preparePeerConnection() error {
if nil != c.pc {
c.pc.Close()
c.pc = nil
@ -161,11 +169,11 @@ func (c *webRTCConn) preparePeerConnection() error {
}
// Create a WebRTC DataChannel locally.
func (c *webRTCConn) establishDataChannel() error {
func (c *WebRTCPeer) establishDataChannel() error {
if c.transport != nil {
panic("Unexpected datachannel already exists!")
}
dc, err := c.pc.CreateDataChannel("snowflake", webrtc.Init{})
dc, err := c.pc.CreateDataChannel(c.id, webrtc.Init{})
// Triggers "OnNegotiationNeeded" on the PeerConnection, which will prepare
// an SDP offer while other goroutines operating on this struct handle the
// signaling. Eventually fires "OnOpen".
@ -220,7 +228,7 @@ func (c *webRTCConn) establishDataChannel() error {
return nil
}
func (c *webRTCConn) sendOfferToBroker() {
func (c *WebRTCPeer) sendOfferToBroker() {
if nil == c.broker {
return
}
@ -235,7 +243,7 @@ func (c *webRTCConn) sendOfferToBroker() {
// Block until an SDP offer is available, send it to either
// the Broker or signal pipe, then await for the SDP answer.
func (c *webRTCConn) exchangeSDP() error {
func (c *WebRTCPeer) exchangeSDP() error {
select {
case offer := <-c.offerChannel:
// Display for copy-paste when no broker available.
@ -272,7 +280,7 @@ func (c *webRTCConn) exchangeSDP() error {
}
// Close all channels and transports
func (c *webRTCConn) cleanup() {
func (c *WebRTCPeer) cleanup() {
if nil != c.offerChannel {
close(c.offerChannel)
}