feat: Add metrics for multiple objects spawned and destroyed (i.e. NetworkShow/Hide) (#935)

Make use of existing network object spawn destroy metrics individually for each network object, so that sent metrics mirror the received metrics, and to avoid allocations.

Co-authored-by: Benoit Doyon <benoit.doyon@unity3d.com>

Author: Josie Messa

com.unity.multiplayer.mlapi/Runtime/Core/NetworkObject.cs

@@ -286,23 +286,23 @@ public static void NetworkShow(List<NetworkObject> networkObjects, ulong clientI
                     throw new ArgumentNullException("All " + nameof(NetworkObject) + "s must belong to the same " + nameof(NetworkManager));
                 }
             }
-
             using (var buffer = PooledNetworkBuffer.Get())
             using (var writer = PooledNetworkWriter.Get(buffer))
             {
                 writer.WriteUInt16Packed((ushort)networkObjects.Count);
-
+                long prevLength = 0;
                 for (int i = 0; i < networkObjects.Count; i++)
                 {
                     // Send spawn call
                     networkObjects[i].Observers.Add(clientId);
 
                     networkManager.SpawnManager.WriteSpawnCallForObject(buffer, clientId, networkObjects[i], payload);
+                    networkManager.NetworkMetrics.TrackObjectSpawnSent(clientId, networkObjects[i].NetworkObjectId, networkObjects[i].name, (ulong)(buffer.Length - prevLength));
+                    prevLength = buffer.Length;
                 }
 
                 networkManager.MessageSender.Send(clientId, NetworkConstants.ADD_OBJECTS, NetworkChannel.Internal, buffer);
             }
-            // TODO: add metric for spawn objects here
         }
 
         /// <summary>
@@ -392,17 +392,20 @@ public static void NetworkHide(List<NetworkObject> networkObjects, ulong clientI
             {
                 writer.WriteUInt16Packed((ushort)networkObjects.Count);
 
+                long prevLength = 0;
+
                 for (int i = 0; i < networkObjects.Count; i++)
                 {
                     // Send destroy call
                     networkObjects[i].Observers.Remove(clientId);
 
                     writer.WriteUInt64Packed(networkObjects[i].NetworkObjectId);
+                    networkManager.NetworkMetrics.TrackObjectDestroySent(clientId, networkObjects[i].NetworkObjectId, networkObjects[i].name, (ulong)(buffer.Length - prevLength));
+                    prevLength = buffer.Length;
                 }
 
                 networkManager.MessageSender.Send(clientId, NetworkConstants.DESTROY_OBJECTS, NetworkChannel.Internal, buffer);
             }
-                // TODO: add metric for destroy objects here
         }
 
         private void OnDestroy()

com.unity.multiplayer.mlapi/Tests/Runtime/Metrics/NetworkObjects/NetworkObjectMetricsTests.cs

@@ -1,4 +1,5 @@
 using System.Collections;
+using System.Collections.Generic;
 using System.Linq;
 using MLAPI.Metrics;
 using NUnit.Framework;
@@ -144,5 +145,80 @@ public IEnumerator TrackNetworkObjectDestroyReceivedMetric()
             // Bug: Currently the object name is always "Player Clone"
             // Assert.AreEqual(m_NewNetworkObjectName, objectDestroyed.NetworkId.Name);
         }
+
+        [UnityTest]
+        public IEnumerator TrackMultipleNetworkObjectDestroySentMetric()
+        {
+            m_NewNetworkObject.Spawn();
+
+            // Spawn another network object so we can hide multiple.
+            var gameObject = new GameObject(m_NewNetworkObjectName);
+            var anotherNetworkObject = gameObject.AddComponent<NetworkObject>();
+            anotherNetworkObject.NetworkManagerOwner = m_Server;
+            anotherNetworkObject.Spawn();
+
+            var waitForMetricEvent = new WaitForMetricValues<ObjectDestroyedEvent>(m_ServerMetrics.Dispatcher, MetricNames.ObjectDestroyedSent);
+            yield return waitForMetricEvent.WaitForAFewFrames();
+
+            NetworkObject.NetworkHide(new List<NetworkObject>{m_NewNetworkObject, anotherNetworkObject}, m_Client.LocalClientId);
+
+            yield return waitForMetricEvent.Wait(60);
+
+            var objectDestroyedSentMetricValues = waitForMetricEvent.EnsureMetricValuesHaveBeenFound();
+            // As there's a client and server, this event is emitted twice.
+            Assert.AreEqual(2, objectDestroyedSentMetricValues.Count);
+
+            var networkIDFound = true;
+            var networkNameFound = true;
+            // not sure that we can guarantee the order of these so just ensure the data is in the received metrics.
+            foreach (var metricValue in objectDestroyedSentMetricValues)
+            {
+                Assert.AreEqual(m_Client.LocalClientId, metricValue.Connection.Id);
+                networkIDFound &= metricValue.NetworkId.NetworkId == m_NewNetworkObject.NetworkObjectId || metricValue.NetworkId.NetworkId == anotherNetworkObject.NetworkObjectId;
+                networkNameFound &= metricValue.NetworkId.Name == m_NewNetworkObject.name || metricValue.NetworkId.Name == anotherNetworkObject.name;
+            }
+            Assert.IsTrue(networkIDFound);
+            Assert.IsTrue(networkNameFound);
+        }
+
+        [UnityTest]
+        public IEnumerator TrackMultipleNetworkObjectSpawnSentMetric()
+        {
+            m_NewNetworkObject.Spawn();
+
+            // Spawn another network object so we can hide multiple.
+            var gameObject = new GameObject(m_NewNetworkObjectName);
+            var anotherNetworkObject = gameObject.AddComponent<NetworkObject>();
+            anotherNetworkObject.NetworkManagerOwner = m_Server;
+            anotherNetworkObject.Spawn();
+
+            var waitForMetricEvent = new WaitForMetricValues<ObjectSpawnedEvent>(m_ServerMetrics.Dispatcher, MetricNames.ObjectSpawnedSent);
+            yield return waitForMetricEvent.WaitForAFewFrames();
+
+            NetworkObject.NetworkHide(new List<NetworkObject>{m_NewNetworkObject, anotherNetworkObject}, m_Client.LocalClientId);
+
+            yield return waitForMetricEvent.WaitForAFewFrames();
+
+            NetworkObject.NetworkShow(new List<NetworkObject>{m_NewNetworkObject, anotherNetworkObject}, m_Client.LocalClientId);
+
+            yield return waitForMetricEvent.Wait(60);
+
+            var objectSpawnedSentMetricValues = waitForMetricEvent.EnsureMetricValuesHaveBeenFound();
+            // As there's a client and server, this event is emitted twice.
+            Assert.AreEqual(2, objectSpawnedSentMetricValues.Count);
+
+            var networkIDFound = true;
+            var networkNameFound = true;
+            // not sure that we can guarantee the order of these so just ensure the data is in the received metrics.
+            foreach (var metricValue in objectSpawnedSentMetricValues)
+            {
+                Assert.AreEqual(m_Client.LocalClientId, metricValue.Connection.Id);
+                networkIDFound &= metricValue.NetworkId.NetworkId == m_NewNetworkObject.NetworkObjectId || metricValue.NetworkId.NetworkId == anotherNetworkObject.NetworkObjectId;
+                networkNameFound &= metricValue.NetworkId.Name == m_NewNetworkObject.name || metricValue.NetworkId.Name == anotherNetworkObject.name;
+            }
+
+            Assert.IsTrue(networkIDFound);
+            Assert.IsTrue(networkNameFound);
+        }
     }
 }