Communicator factory (#4965)

Author: Chris Elion

com.unity.ml-agents/Runtime/Academy.cs

@@ -422,12 +422,7 @@ void InitializeEnvironment()
             var port = ReadPortFromArgs();
             if (port > 0)
             {
-                Communicator = new RpcCommunicator(
-                    new CommunicatorInitParameters
-                    {
-                        port = port
-                    }
-                );
+                Communicator = CommunicatorFactory.Create();
             }
 
             if (Communicator != null)
@@ -438,6 +433,7 @@ void InitializeEnvironment()
                 bool initSuccessful = false;
                 var communicatorInitParams = new CommunicatorInitParameters
                 {
+                    port = port,
                     unityCommunicationVersion = k_ApiVersion,
                     unityPackageVersion = k_PackageVersion,
                     name = "AcademySingleton",

com.unity.ml-agents/Runtime/Communicator/CommunicatorFactory.cs

@@ -0,0 +1,35 @@
+namespace Unity.MLAgents
+{
+    /// <summary>
+    /// Factory class for an ICommunicator instance. This is used to the <see cref="Academy"/> at startup.
+    /// By default, on desktop platforms, an ICommunicator will be created and attempt to connect
+    /// to a trainer. This behavior can be prevented by setting <see cref="CommunicatorFactory.Enabled"/> to false
+    /// *before* the <see cref="Academy"/> is initialized.
+    /// </summary>
+    public static class CommunicatorFactory
+    {
+        static bool s_Enabled = true;
+
+        /// <summary>
+        /// Whether or not an ICommunicator instance will be created when the <see cref="Academy"/> is initialized.
+        /// Changing this has no effect after the <see cref="Academy"/> has already been initialized.
+        /// </summary>
+        public static bool Enabled
+        {
+            get => s_Enabled;
+            set => s_Enabled = value;
+        }
+
+        internal static ICommunicator Create()
+        {
+#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
+            if (s_Enabled)
+            {
+                return new RpcCommunicator();
+            }
+#endif
+            // Non-desktop or disabled
+            return null;
+        }
+    }
+}

com.unity.ml-agents/Runtime/Communicator/CommunicatorFactory.cs.meta

@@ -1,6 +1,5 @@
-# if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
+#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
 using Grpc.Core;
-#endif
 #if UNITY_EDITOR
 using UnityEditor;
 #endif
@@ -44,23 +43,17 @@ internal class RpcCommunicator : ICommunicator
         Dictionary<string, ActionSpec> m_UnsentBrainKeys = new Dictionary<string, ActionSpec>();
 
 
-#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
         /// The Unity to External client.
         UnityToExternalProto.UnityToExternalProtoClient m_Client;
-#endif
-        /// The communicator parameters sent at construction
-        CommunicatorInitParameters m_CommunicatorInitParameters;
 
         /// <summary>
         /// Initializes a new instance of the RPCCommunicator class.
         /// </summary>
-        /// <param name="communicatorInitParameters">Communicator parameters.</param>
-        public RpcCommunicator(CommunicatorInitParameters communicatorInitParameters)
+        public RpcCommunicator()
         {
-            m_CommunicatorInitParameters = communicatorInitParameters;
         }
 
-        #region Initialization
+#region Initialization
 
         internal static bool CheckCommunicationVersionsAreCompatible(
             string unityCommunicationVersion,
@@ -110,6 +103,7 @@ public bool Initialize(CommunicatorInitParameters initParameters, out UnityRLIni
             try
             {
                 initializationInput = Initialize(
+                    initParameters.port,
                     new UnityOutputProto
                     {
                         RlInitializationOutput = academyParameters
@@ -211,13 +205,10 @@ void UpdateEnvironmentWithInput(UnityRLInputProto rlInput)
             SendCommandEvent(rlInput.Command);
         }
 
-        UnityInputProto Initialize(UnityOutputProto unityOutput, out UnityInputProto unityInput)
+        UnityInputProto Initialize(int port, UnityOutputProto unityOutput, out UnityInputProto unityInput)
         {
-#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
             m_IsOpen = true;
-            var channel = new Channel(
-                "localhost:" + m_CommunicatorInitParameters.port,
-                ChannelCredentials.Insecure);
+            var channel = new Channel($"localhost:{port}", ChannelCredentials.Insecure);
 
             m_Client = new UnityToExternalProto.UnityToExternalProtoClient(channel);
             var result = m_Client.Exchange(WrapMessage(unityOutput, 200));
@@ -232,21 +223,17 @@ UnityInputProto Initialize(UnityOutputProto unityOutput, out UnityInputProto uni
                 QuitCommandReceived?.Invoke();
             }
             return result.UnityInput;
-#else
-            throw new UnityAgentsException("You cannot perform training on this platform.");
-#endif
         }
 
-        #endregion
+#endregion
 
-        #region Destruction
+#region Destruction
 
         /// <summary>
         /// Close the communicator gracefully on both sides of the communication.
         /// </summary>
         public void Dispose()
         {
-#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
             if (!m_IsOpen)
             {
                 return;
@@ -261,15 +248,11 @@ public void Dispose()
             {
                 // ignored
             }
-#else
-            throw new UnityAgentsException(
-                "You cannot perform training on this platform.");
-#endif
         }
 
-        #endregion
+#endregion
 
-        #region Sending Events
+#region Sending Events
 
         void SendCommandEvent(CommandProto command)
         {
@@ -296,9 +279,9 @@ void SendCommandEvent(CommandProto command)
             }
         }
 
-        #endregion
+#endregion
 
-        #region Sending and retreiving data
+#region Sending and retreiving data
 
         public void DecideBatch()
         {
@@ -447,7 +430,6 @@ public ActionBuffers GetActions(string behaviorName, int agentId)
         /// <param name="unityOutput">The UnityOutput to be sent.</param>
         UnityInputProto Exchange(UnityOutputProto unityOutput)
         {
-#if UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX
             if (!m_IsOpen)
             {
                 return null;
@@ -500,10 +482,6 @@ UnityInputProto Exchange(UnityOutputProto unityOutput)
                 QuitCommandReceived?.Invoke();
                 return null;
             }
-#else
-            throw new UnityAgentsException(
-                "You cannot perform training on this platform.");
-#endif
         }
 
         /// <summary>
@@ -573,7 +551,7 @@ void UpdateSentActionSpec(UnityRLInitializationOutputProto output)
             }
         }
 
-        #endregion
+#endregion
 
 #if UNITY_EDITOR
         /// <summary>
@@ -592,3 +570,4 @@ void HandleOnPlayModeChanged(PlayModeStateChange state)
 #endif
     }
 }
+#endif // UNITY_EDITOR || UNITY_STANDALONE_WIN || UNITY_STANDALONE_OSX || UNITY_STANDALONE_LINUX