Implement PeerConnection.getStats() for iOS (#161)

Author: evdokimovs

android/src/main/kotlin/com/instrumentisto/medea_flutter_webrtc/model/RtcStats.kt

@@ -28,6 +28,7 @@ data class RtcStats(
 
   /** Converts these [RtcStats] into a [Map] which can be returned to the Flutter side. */
   fun asFlutterResult(): Map<String, Any> {
-    return mapOf("id" to id, "timestampUs" to timestampUs, "kind" to kind, "type" to type)
+    var report = mapOf("id" to id, "timestampUs" to timestampUs, "type" to type)
+    return report + kind
   }
 }

example/integration_test/webrtc_test.dart

@@ -1186,10 +1186,6 @@ void main() {
   });
 
   testWidgets('Peer connection get stats.', (WidgetTester tester) async {
-    // TODO: Support stats for iOS platform.
-    if (Platform.isIOS) {
-      return;
-    }
     var pc1 = await PeerConnection.create(IceTransportType.all, []);
     var pc2 = await PeerConnection.create(IceTransportType.all, []);
 

ios/Classes/controller/PeerConnectionController.swift

@@ -139,6 +139,15 @@ class PeerConnectionController {
           self.sendResultFromTask(result, getFlutterError(error))
         }
       }
+    case "getStats":
+      Task {
+        do {
+          let report = try await self.peer.getStats()
+          self.sendResultFromTask(result, report.asFlutterResult())
+        } catch {
+          self.sendResultFromTask(result, getFlutterError(error))
+        }
+      }
     case "addTransceiver":
       let mediaType = argsMap!["mediaType"] as? Int
       let initArgs = argsMap!["init"] as? [String: Any]

ios/Classes/model/RtcStats.swift

@@ -0,0 +1,27 @@
+/// Representation of an `RTCStatisticsReport`.
+class RtcStats {
+  /// List of all RTC stats reports converted to flat `Map`.
+  var statsList: [[String: Any]] = []
+
+  /// Converts the provided `RTCStatisticsReport` into `RtcStats`.
+  init(report: RTCStatisticsReport) {
+    for (_, stats) in report.statistics {
+      var statDetails: [String: Any] = [:]
+      statDetails["id"] = stats.id
+      statDetails["type"] = stats.type
+      statDetails["timestampUs"] = Int(stats.timestamp_us)
+
+      for (statName, statValue) in stats.values {
+        statDetails[statName] = statValue
+      }
+
+      self.statsList.append(statDetails)
+    }
+  }
+
+  /// Converts these `RtcStats` into a `Map` which can be returned to the
+  /// Flutter side.
+  func asFlutterResult() -> [[String: Any]] {
+    return self.statsList
+  }
+}

ios/Classes/proxy/PeerConnectionProxy.swift

@@ -39,6 +39,19 @@ class PeerConnectionProxy {
     self.id
   }
 
+  /// Returns `RtcStats` of this `PeerConnectionProxy`.
+  func getStats() async throws -> RtcStats {
+    return try await withCheckedThrowingContinuation { continuation in
+      do {
+        try self.peer.statistics { report in
+          continuation.resume(returning: RtcStats(report: report))
+        }
+      } catch {
+        continuation.resume(throwing: error)
+      }
+    }
+  }
+
   /// Synchronizes and returns all the `RtpTransceiverProxy`s of this
   /// `PeerConnectionProxy`.
   func getTransceivers() -> [RtpTransceiverProxy] {

lib/src/model/stats.dart

@@ -54,8 +54,7 @@ class RtcStats {
 
   /// Creates [RTCStats] basing on the [Map] received from the native side.
   static RtcStats? fromMap(dynamic stats) {
-    stats['kind']['type'] = stats['type'];
-    var kind = RtcStatsType.fromMap(stats['kind']);
+    var kind = RtcStatsType.fromMap(stats);
     if (kind == null) {
       return null;
     } else {