[MV-410] Add getStats function

MembraneRTC/Sources/MembraneRTC/MembraneRTC.swift

@@ -433,6 +433,15 @@ public class MembraneRTC: MulticastDelegate<MembraneRTCDelegate>, ObservableObje
         peerConnectionManager.setTrackEncoding(trackId: trackId, encoding: encoding, enabled: enabled)
     }
 
+    /**
+     Returns current connection stats.
+
+     - Returns: a map containing statistics
+     */
+    public func getStats() -> [String: RTCStats] {
+        return peerConnectionManager.getStats()
+    }
+
     /**
      Changes severity level of debug logs.
 

MembraneRTC/Sources/MembraneRTC/PeerConnectionManager.swift

@@ -26,6 +26,8 @@ internal class PeerConnectionManager: NSObject, RTCPeerConnectionDelegate {
 
     private let peerConnectionListener: PeerConnectionListener
 
+    private var peerConnectionStats: [String: RTCStats] = [:]
+
     internal init(
         config: RTCConfiguration, peerConnectionFactory: PeerConnectionFactoryWrapper,
         peerConnectionListener: PeerConnectionListener
@@ -274,6 +276,57 @@ internal class PeerConnectionManager: NSObject, RTCPeerConnectionDelegate {
         sender.parameters = params
     }
 
+    private func extractRelevantStats(rp: RTCStatisticsReport) {
+        rp.statistics.forEach { it1 in
+            let it = it1.value
+            if it.type == "outbound-rtp" {
+                let duration = it.values["qualityLimitationDurations"] as? [String: Double]
+                let qualityLimitation: QualityLimitationDurations = QualityLimitationDurations(
+                    bandwidth: duration?["bandwidth"] ?? 0.0,
+                    cpu: duration?["cpu"] ?? 0.0, none: duration?["none"] ?? 0.0, other: duration?["other"] ?? 0.0)
+
+                let tmp = RTCOutboundStats(
+                    kind: it.values["kind"] as? String ?? "",
+                    rid: it.values["rid"] as? String ?? "",
+                    bytesSent: it.values["bytesSent"] as? UInt ?? 0,
+                    targetBitrate: it.values["targetBitrate"] as? Double ?? 0.0,
+                    packetsSent: it.values["packetsSent"] as? UInt ?? 0,
+                    framesEncoded: it.values["framesEncoded"] as? UInt ?? 0,
+                    framesPerSecond: it.values["framesPerSecond"] as? Double ?? 0.0,
+                    frameWidth: it.values["frameWidth"] as? UInt ?? 0,
+                    frameHeight: it.values["frameHeight"] as? UInt ?? 0,
+                    qualityLimitationDurations: qualityLimitation
+                )
+
+                peerConnectionStats[it.id as String] = tmp
+            } else if it.type == "inbound-rtp" {
+                let tmp = RTCInboundStats(
+                    kind: it.values["kind"] as? String ?? "",
+                    jitter: it.values["jitter"] as? Double ?? 0.0,
+                    packetsLost: it.values["packetsLost"] as? UInt ?? 0,
+                    packetsReceived: it.values["packetsReceived"] as? UInt ?? 0,
+                    bytesReceived: it.values["bytesReceived"] as? UInt ?? 0,
+                    framesReceived: it.values["framesReceived"] as? UInt ?? 0,
+                    frameWidth: it.values["frameWidth"] as? UInt ?? 0,
+                    frameHeight: it.values["frameHeight"] as? UInt ?? 0,
+                    framesPerSecond: it.values["framesPerSecond"] as? Double ?? 0.0,
+                    framesDropped: it.values["framesDropped"] as? UInt ?? 0
+                )
+
+                peerConnectionStats[it.id as String] = tmp
+            }
+        }
+    }
+
+    public func getStats() -> [String: RTCStats] {
+        if let connection = connection {
+            connection.statistics(completionHandler: { RTCStatisticsReport in
+                self.extractRelevantStats(rp: RTCStatisticsReport)
+            })
+        }
+        return peerConnectionStats
+    }
+
     private func applyBitrate(encodings: [RTCRtpEncodingParameters], maxBitrate: TrackBandwidthLimit) {
         switch maxBitrate {
         case .BandwidthLimit(let limit):

MembraneRTC/Sources/MembraneRTC/Types/RTCStats.swift

@@ -0,0 +1,76 @@
+public struct QualityLimitationDurations {
+    public let bandwidth: Double
+    public let cpu: Double
+    public let none: Double
+    public let other: Double
+
+    public init(bandwidth: Double, cpu: Double, none: Double, other: Double) {
+        self.bandwidth = bandwidth
+        self.cpu = cpu
+        self.none = none
+        self.other = other
+    }
+}
+
+public protocol RTCStats {}
+
+public struct RTCOutboundStats: RTCStats {
+    public let kind: String
+    public let rid: String
+    public let bytesSent: UInt
+    public let targetBitrate: Double
+    public let packetsSent: UInt
+    public let framesEncoded: UInt
+    public let framesPerSecond: Double
+    public let frameWidth: UInt
+    public let frameHeight: UInt
+    public let qualityLimitationDurations: QualityLimitationDurations?
+
+    public init(
+        kind: String = "", rid: String = "", bytesSent: UInt = 0, targetBitrate: Double = 0.0, packetsSent: UInt = 0,
+        framesEncoded: UInt = 0, framesPerSecond: Double = 0.0, frameWidth: UInt = 0, frameHeight: UInt = 0,
+        qualityLimitationDurations: QualityLimitationDurations? = nil
+    ) {
+        self.kind = kind
+        self.rid = rid
+        self.bytesSent = bytesSent
+        self.targetBitrate = targetBitrate
+        self.packetsSent = packetsSent
+        self.framesEncoded = framesEncoded
+        self.framesPerSecond = framesPerSecond
+        self.frameWidth = frameWidth
+        self.frameHeight = frameHeight
+        self.qualityLimitationDurations = qualityLimitationDurations
+    }
+}
+
+public struct RTCInboundStats: RTCStats {
+    public let kind: String
+    public let jitter: Double
+    public let packetsLost: UInt
+    public let packetsReceived: UInt
+    public let bytesReceived: UInt
+    public let framesReceived: UInt
+    public let frameWidth: UInt
+    public let frameHeight: UInt
+    public let framesPerSecond: Double
+    public let framesDropped: UInt
+
+    public init(
+        kind: String = "", jitter: Double = 0.0, packetsLost: UInt = 0, packetsReceived: UInt = 0,
+        bytesReceived: UInt = 0,
+        framesReceived: UInt = 0, frameWidth: UInt = 0, frameHeight: UInt = 0, framesPerSecond: Double = 0.0,
+        framesDropped: UInt = 0
+    ) {
+        self.kind = kind
+        self.jitter = jitter
+        self.packetsLost = packetsLost
+        self.packetsReceived = packetsReceived
+        self.bytesReceived = bytesReceived
+        self.framesReceived = framesReceived
+        self.frameWidth = frameWidth
+        self.frameHeight = frameHeight
+        self.framesPerSecond = framesPerSecond
+        self.framesDropped = framesDropped
+    }
+}