commit 7187f1009ef7aaae6aa557fe1f724aa1df718b24 Author: Cecylia Bocovich cohosh@torproject.org Date: Mon Jan 25 13:01:37 2021 -0500
Log a throughput summary for each connection
This will increase transparency for people running standalone proxies and help us debug any potential issues with proxies behaving unreliably. --- proxy/snowflake.go | 6 ++++ proxy/util.go | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 90 insertions(+)
diff --git a/proxy/snowflake.go b/proxy/snowflake.go index 1bc21ab..86ae0b2 100644 --- a/proxy/snowflake.go +++ b/proxy/snowflake.go @@ -118,6 +118,8 @@ type webRTCConn struct {
lock sync.Mutex // Synchronization for DataChannel destruction once sync.Once // Synchronization for PeerConnection destruction + + bytesLogger BytesLogger }
func (c *webRTCConn) Read(b []byte) (int, error) { @@ -125,6 +127,7 @@ func (c *webRTCConn) Read(b []byte) (int, error) { }
func (c *webRTCConn) Write(b []byte) (int, error) { + c.bytesLogger.AddInbound(len(b)) c.lock.Lock() defer c.lock.Unlock() if c.dc != nil { @@ -368,6 +371,7 @@ func makePeerConnectionFromOffer(sdp *webrtc.SessionDescription,
pr, pw := io.Pipe() conn := &webRTCConn{pc: pc, dc: dc, pr: pr} + conn.bytesLogger = NewBytesSyncLogger()
dc.OnOpen(func() { log.Println("OnOpen channel") @@ -376,6 +380,7 @@ func makePeerConnectionFromOffer(sdp *webrtc.SessionDescription, conn.lock.Lock() defer conn.lock.Unlock() log.Println("OnClose channel") + log.Println(conn.bytesLogger.ThroughputSummary()) conn.dc = nil dc.Close() pw.Close() @@ -388,6 +393,7 @@ func makePeerConnectionFromOffer(sdp *webrtc.SessionDescription, log.Printf("close with error generated an error: %v", inerr) } } + conn.bytesLogger.AddOutbound(n) if n != len(msg.Data) { panic("short write") } diff --git a/proxy/util.go b/proxy/util.go new file mode 100644 index 0000000..d737056 --- /dev/null +++ b/proxy/util.go @@ -0,0 +1,84 @@ +package main + +import ( + "fmt" + "time" +) + +type BytesLogger interface { + AddOutbound(int) + AddInbound(int) + ThroughputSummary() string +} + +// Default BytesLogger does nothing. +type BytesNullLogger struct{} + +func (b BytesNullLogger) AddOutbound(amount int) {} +func (b BytesNullLogger) AddInbound(amount int) {} +func (b BytesNullLogger) ThroughputSummary() string { return "" } + +// BytesSyncLogger uses channels to safely log from multiple sources with output +// occuring at reasonable intervals. +type BytesSyncLogger struct { + outboundChan, inboundChan chan int + outbound, inbound, outEvents, inEvents int + start time.Time +} + +// NewBytesSyncLogger returns a new BytesSyncLogger and starts it loggin. +func NewBytesSyncLogger() *BytesSyncLogger { + b := &BytesSyncLogger{ + outboundChan: make(chan int, 5), + inboundChan: make(chan int, 5), + } + go b.log() + b.start = time.Now() + return b +} + +func (b *BytesSyncLogger) log() { + for { + select { + case amount := <-b.outboundChan: + b.outbound += amount + b.outEvents++ + case amount := <-b.inboundChan: + b.inbound += amount + b.inEvents++ + } + } +} + +func (b *BytesSyncLogger) AddOutbound(amount int) { + b.outboundChan <- amount +} + +func (b *BytesSyncLogger) AddInbound(amount int) { + b.inboundChan <- amount +} + +func (b *BytesSyncLogger) ThroughputSummary() string { + var inUnit, outUnit string + units := []string{"B", "KB", "MB", "GB"} + + inbound := b.inbound + outbound := b.outbound + + for i, u := range units { + inUnit = u + if (inbound < 1000) || (i == len(units)-1) { + break + } + inbound = inbound / 1000 + } + for i, u := range units { + outUnit = u + if (outbound < 1000) || (i == len(units)-1) { + break + } + outbound = outbound / 1000 + } + t := time.Now() + return fmt.Sprintf("Traffic throughput (up|down): %d %s|%d %s -- (%d OnMessages, %d Sends, over %d seconds)", inbound, inUnit, outbound, outUnit, b.outEvents, b.inEvents, int(t.Sub(b.start).Seconds())) +}