commit 47e1338290359755308825ca66008e2df94cab60 Author: Serene H git@keroserene.net Date: Tue Sep 20 06:26:21 2016 -0700

initial client roundtrip estimate on broker --- broker/broker.go | 25 ++++++++++++++++++------- broker/metrics.go | 17 +++++++++++++++++ client/torrc | 2 +- proxy/snowflake.coffee | 1 + 4 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/broker/broker.go b/broker/broker.go index 3c50ac9..3561141 100644 --- a/broker/broker.go +++ b/broker/broker.go @@ -26,6 +26,7 @@ type BrokerContext struct { // the second http POST. idToSnowflake map[string]*Snowflake proxyPolls chan *ProxyPoll + metrics *Metrics }

func NewBrokerContext() *BrokerContext { @@ -35,6 +36,7 @@ func NewBrokerContext() *BrokerContext { snowflakes: snowflakes, idToSnowflake: make(map[string]*Snowflake), proxyPolls: make(chan *ProxyPoll), + metrics: new(Metrics), } }

@@ -67,7 +69,7 @@ func (ctx *BrokerContext) RequestOffer(id string) []byte { request.id = id request.offerChannel = make(chan []byte) ctx.proxyPolls <- request - // Block until an offer is available... + // Block until an offer is available, or timeout which sends a nil offer. offer := <-request.offerChannel return offer } @@ -96,6 +98,8 @@ func (ctx *BrokerContext) Broker() { }

// Create and add a Snowflake to the heap. +// Required to keep track of proxies between providing them +// with an offer and awaiting their second POST with an answer. func (ctx *BrokerContext) AddSnowflake(id string) *Snowflake { snowflake := new(Snowflake) snowflake.id = id @@ -141,29 +145,32 @@ snowflake proxy, which responds with the SDP answer to be sent in the HTTP response back to the client. */ func clientOffers(ctx *BrokerContext, w http.ResponseWriter, r *http.Request) { + startTime := time.Now() offer, err := ioutil.ReadAll(r.Body) if nil != err { log.Println("Invalid data.") w.WriteHeader(http.StatusBadRequest) return } - - // Find the most available snowflake proxy, and pass the offer to it. - // TODO: Needs improvement - maybe shouldn't immediately fail? + // Immediately fail if there are no snowflakes available. if ctx.snowflakes.Len() <= 0 { log.Println("Client: No snowflake proxies available.") w.WriteHeader(http.StatusServiceUnavailable) return } + // Otherwise, find the most available snowflake proxy, and pass the offer to it. snowflake := heap.Pop(ctx.snowflakes).(*Snowflake) - defer delete(ctx.idToSnowflake, snowflake.id) + delete(ctx.idToSnowflake, snowflake.id) snowflake.offerChannel <- offer

- // Wait for the answer to be returned on the channel. + // Wait for the answer to be returned on the channel or timeout. select { case answer := <-snowflake.answerChannel: log.Println("Client: Retrieving answer") w.Write(answer) + // Initial tracking of elapsed time. + ctx.metrics.clientRoundtripEstimate = time.Since(startTime) / + time.Millisecond case <-time.After(time.Second * ClientTimeout): log.Println("Client: Timed out.") w.WriteHeader(http.StatusGatewayTimeout) @@ -196,7 +203,11 @@ func proxyAnswers(ctx *BrokerContext, w http.ResponseWriter, r *http.Request) { }

func debugHandler(ctx *BrokerContext, w http.ResponseWriter, r *http.Request) { - s := fmt.Sprintf("current: %d", ctx.snowflakes.Len()) + s := fmt.Sprintf("current snowflakes available: %d\n", ctx.snowflakes.Len()) + for _, snowflake := range ctx.idToSnowflake { + s += fmt.Sprintf("\nsnowflake %d: %s", snowflake.index, snowflake.id) + } + s += fmt.Sprintf("\n\nroundtrip avg: %d", ctx.metrics.clientRoundtripEstimate) w.Write([]byte(s)) }

diff --git a/broker/metrics.go b/broker/metrics.go new file mode 100644 index 0000000..f64d1cc --- /dev/null +++ b/broker/metrics.go @@ -0,0 +1,17 @@ +package snowflake_broker + +import ( + // "golang.org/x/net/internal/timeseries" + "time" +) + +// Implements Observable +type Metrics struct { + // snowflakes timeseries.Float + clientRoundtripEstimate time.Duration +} + +func NewMetrics() *Metrics { + m := new(Metrics) + return m +} diff --git a/client/torrc b/client/torrc index d066454..6912760 100644 --- a/client/torrc +++ b/client/torrc @@ -5,6 +5,6 @@ ClientTransportPlugin snowflake exec ./client \ -url https://snowflake-reg.appspot.com/ \ -front www.google.com \ -ice stun:stun.l.google.com:19302 \ --max 1 +-max 3

Bridge snowflake 0.0.3.0:1 diff --git a/proxy/snowflake.coffee b/proxy/snowflake.coffee index c16694c..8877470 100644 --- a/proxy/snowflake.coffee +++ b/proxy/snowflake.coffee @@ -125,6 +125,7 @@ class Snowflake try offer = JSON.parse desc dbg 'Received:\n\n' + offer.sdp + '\n' + console.log offer sdp = new SessionDescription offer @sendAnswer pair if pair.receiveWebRTCOffer sdp catch e