Shutting down MLAPI while in an RPC.

[daniellochner]

The following error is logged when you try to invoke NetworkManager.StopClient() from within an RPC:

Invoke Test() from the server:

[ClientRpc]
public void TestClientRpc()
{
    NetworkManager.StopClient();
}

public void Test()
{
    TestClientRpc();
}

Environment:

• OS: Windows 10
• Unity Version: 2020.2.3f1
• MLAPI Version: v0.1.0

[Ratstail91]

This is likely the cause of my troubles here: #936

[NoelStephensUnity]

Hi daniellochner,
We will look into a more optimal way to handle this specific scenario.
For the time being, we would recommend setting a bool that signals the client should shutdown and make that call outside of the RPC. When you call StopClient, StopHost, or StopServer all of the systems the NetworkManager instantiates are destroyed including the RPCQueue and as such the error you are getting.

[will-mearns]

Committing this into our backlog at MTT-856

[0xFA11]

Currently CNR, PR #948 probably fixed this issue too.

More specifically this block:

com.unity.netcode.gameobjects/com.unity.netcode.gameobjects/Runtime/Core/NetworkManager.cs

Line 866 in 847068b

// make sure all messages are flushed before transport disconnect clients

Please feel free to open this issue if this bug reproduces.

[daniellochner]

Hi @MFatihMAR, I unfortunately still have this issue (however it's a new error message):

ObjectDisposedException: The Unity.Collections.NativeList`1[Unity.Netcode.MessagingSystem+ReceiveQueueItem] has been deallocated, it is not allowed to access it
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckReadAndThrowNoEarlyOut (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) (at <07c89f7520694139991332d3cf930d48>:0)
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckReadAndThrow (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) (at <07c89f7520694139991332d3cf930d48>:0)
Unity.Collections.NativeList`1[T].get_Length () (at Library/PackageCache/com.unity.collections@1.0.0-pre.5/Unity.Collections/NativeList.cs:232)
Unity.Netcode.MessagingSystem.ProcessIncomingMessageQueue () (at Library/PackageCache/com.unity.netcode.gameobjects@1.0.0-pre.3/Runtime/Messaging/MessagingSystem.cs:256)
Unity.Netcode.NetworkManager.OnNetworkEarlyUpdate () (at Library/PackageCache/com.unity.netcode.gameobjects@1.0.0-pre.3/Runtime/Core/NetworkManager.cs:1154)
Unity.Netcode.NetworkManager.NetworkUpdate (Unity.Netcode.NetworkUpdateStage updateStage) (at Library/PackageCache/com.unity.netcode.gameobjects@1.0.0-pre.3/Runtime/Core/NetworkManager.cs:1125)
Unity.Netcode.NetworkUpdateLoop.RunNetworkUpdateStage (Unity.Netcode.NetworkUpdateStage updateStage) (at Library/PackageCache/com.unity.netcode.gameobjects@1.0.0-pre.3/Runtime/Core/NetworkUpdateLoop.cs:149)
Unity.Netcode.NetworkUpdateLoop+NetworkEarlyUpdate+<>c.<CreateLoopSystem>b__0_0 () (at Library/PackageCache/com.unity.netcode.gameobjects@1.0.0-pre.3/Runtime/Core/NetworkUpdateLoop.cs:172)