From d5c934f2af7ffb1b5f228aef7b6d2c3b3e0f55e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miroslav=20=C5=A0ediv=C3=BD?= <sedivy.miro@gmail.com>
Date: Mon, 4 Jul 2022 01:01:03 +0200
Subject: [PATCH] add ReceiverReport.

---
 internal/webrtc/manager.go |  7 +++++++
 internal/webrtc/metrics.go | 41 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/internal/webrtc/manager.go b/internal/webrtc/manager.go
index 7bf18d41..cc8523a9 100644
--- a/internal/webrtc/manager.go
+++ b/internal/webrtc/manager.go
@@ -404,6 +404,13 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 		switch rtcpPacket := p.(type) {
 		case *rtcp.ReceiverEstimatedMaximumBitrate: // TODO: Deprecated.
 			manager.metrics.SetReceiverEstimatedMaximumBitrate(session, rtcpPacket.Bitrate)
+
+		case *rtcp.ReceiverReport:
+			l := len(rtcpPacket.Reports)
+			if l > 0 {
+				// use only last report
+				manager.metrics.SetReceiverReport(session, rtcpPacket.Reports[l-1])
+			}
 		}
 	})
 
diff --git a/internal/webrtc/metrics.go b/internal/webrtc/metrics.go
index c386e0d3..8c1f4143 100644
--- a/internal/webrtc/metrics.go
+++ b/internal/webrtc/metrics.go
@@ -3,6 +3,7 @@ package webrtc
 import (
 	"sync"
 
+	"github.com/pion/rtcp"
 	"github.com/pion/webrtc/v3"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
@@ -23,6 +24,10 @@ type metrics struct {
 
 	receiverEstimatedMaximumBitrate prometheus.Gauge
 
+	receiverReportDelay     prometheus.Gauge
+	receiverReportJitter    prometheus.Gauge
+	receiverReportTotalLost prometheus.Gauge
+
 	iceBytesSent      prometheus.Gauge
 	iceBytesReceived  prometheus.Gauge
 	sctpBytesSent     prometheus.Gauge
@@ -104,6 +109,34 @@ func (m *metricsCtx) getBySession(session types.Session) metrics {
 			},
 		}),
 
+		receiverReportDelay: promauto.NewGauge(prometheus.GaugeOpts{
+			Name:      "receiver_report_delay",
+			Namespace: "neko",
+			Subsystem: "webrtc",
+			Help:      "Receiver Report Delay from SCTP, expressed in units of 1/65536 seconds.",
+			ConstLabels: map[string]string{
+				"session_id": session.ID(),
+			},
+		}),
+		receiverReportJitter: promauto.NewGauge(prometheus.GaugeOpts{
+			Name:      "receiver_report_jitter",
+			Namespace: "neko",
+			Subsystem: "webrtc",
+			Help:      "Receiver Report Jitter from SCTP.",
+			ConstLabels: map[string]string{
+				"session_id": session.ID(),
+			},
+		}),
+		receiverReportTotalLost: promauto.NewGauge(prometheus.GaugeOpts{
+			Name:      "receiver_report_total_lost",
+			Namespace: "neko",
+			Subsystem: "webrtc",
+			Help:      "Receiver Report Total Lost from SCTP.",
+			ConstLabels: map[string]string{
+				"session_id": session.ID(),
+			},
+		}),
+
 		iceBytesSent: promauto.NewGauge(prometheus.GaugeOpts{
 			Name:      "bytes_sent",
 			Namespace: "neko",
@@ -227,6 +260,14 @@ func (m *metricsCtx) SetReceiverEstimatedMaximumBitrate(session types.Session, b
 	met.receiverEstimatedMaximumBitrate.Set(float64(bitrate))
 }
 
+func (m *metricsCtx) SetReceiverReport(session types.Session, report rtcp.ReceptionReport) {
+	met := m.getBySession(session)
+
+	met.receiverReportDelay.Set(float64(report.Delay))
+	met.receiverReportJitter.Set(float64(report.Jitter))
+	met.receiverReportTotalLost.Set(float64(report.TotalLost))
+}
+
 func (m *metricsCtx) SetIceTransportStats(session types.Session, data webrtc.TransportStats) {
 	met := m.getBySession(session)