Unexpected token readed 'BeginArray' while 'BeginObject' is expected.

[Mol0ko]

Hi. I am using masgpack along with Best Http/2 in Unity project to deserialize SignalR messages. I used this guide to set it. I can't fix the following exception:

{"tid":1,"div":"WebSocketTransport","msg":"OnMessage(byte[])
","ex": [{"msg": "Unexpected token readed 'BeginArray' while 'BeginObject' is expected.", 
"stack": "  at GameDevWare.Serialization.Serializers.ObjectSerializer.Deserialize 
(GameDevWare.Serialization.IJsonReader reader) [0x00026] in ...

Here is my code for SignalR hub connection:

_connection = new HubConnection(url, new MessagePackProtocol(), options);
_connection.On<StepResponseMessage>("Step", (step) =>
{
    Debug.Log("Step.result: " + step.Result);
});

Here is response message model:

[DataContract]
public class StepResponseMessage
{
    [DataMember(Order = 0)]
    public int Turn { get; set; }
    [DataMember(Order = 1)]
    public long TimeMicroseconds { get; set; }
    [DataMember(Order = 2)]
    public IReadOnlyList<MatchCollection> Changes { get; set; }
    [DataMember(Order = 3)]
    public IReadOnlyList<AttackInfo> Player { get; set; }
    [DataMember(Order = 4)]
    public IReadOnlyList<RecoveryInfo> PlayerRecovery { get; set; }
    [DataMember(Order = 5)]
    public IReadOnlyList<AttackInfo> Enemy { get; set; }
    [DataMember(Order = 6)]
    public IReadOnlyList<RecoveryInfo> EnemyRecovery { get; set; }
    [DataMember(Order = 7)]
    public string? Result { get; set; }
    [DataMember(Order = 8)]
    public IReadOnlyList<AbilityInfo> PlayerAbilities { get; set; }
    [DataMember(Order = 9)]
    public IReadOnlyList<AbilityInfo> EnemyAbilities { get; set; }
    [DataMember(Order = 10)]
    public IReadOnlyList<GenericAbilityActionInfo> AbilityActions { get; set; }
}

Without _connection.On<StepResponseMessage> call I get the following message to message _connection.OnMessage callback:

I am sure that StepResponseMessage corresponds to the messagepack object from arguments. I am using v2.4.3 from asset store.

Could you help me with it? Am I do something wrong? Thanks.

[deniszykov]

Hi @Mol0ko! This is must be Dictionary<KeyT, ValueT> representation problem. Some serializers serialize them as arrays of [key, value] tuples, and some as arrays of { "key": xxx, "value": xxx } objects. Can you transform message.arguments[0] to JSON and review find where such Dictionary is located and how it is represented (tuples/objects etc).

 GameDevWare.Serialization.Json.SerializeToString(message.arguments[0]);

[Mol0ko]

@deniszykov thanks for your answer. Here is an example of GameDevWare.Serialization.Json.SerializeToString(message.arguments[0]);:

[
  1,
  1632823892325699,
  [
    [
      [
        [
          [3,0,1,3,1,3],
          [2,0,0,3,2,3],
          [3,2,2,0,1,0],
          [2,1,0,2,1,1],
          [3,3,2,1,3,3]
        ]
      ],
      []
    ]
  ],
  [],
  [],
  [
    [0,1,1.2,66,2664,null,null],
    [1,1,1.2,22,2642,null,null]
  ],
  [],
  null,
  [
    [0,1,false,false],
    [1,1,false,false],
    [2,1,false,false],
    [3,1,false,false],
    [4,1,false,false]
  ],
  [
    [0,1,false,false],
    [1,1,false,false],
    [2,1,false,false],
    [3,1,false,false],
    [4,1,false,false]
  ],
  []
]

[deniszykov]

He is problem, all your object are represented as tuples [a,b,c,d] instead of objects { a: x, b: x, c: x, d: x}. You need to tune server-size serializer to send object or write custom object serializer for tuples and register it in SerializationContext.SerializerFactory

[BinhNguyenPSA]

I have the same problem, I found that if I remove the attribute [DataContract] everything will work ok.

[BinhNguyenPSA]

@deniszykov could you please write the "write custom object serializer for tuples and register it in" you mention above :-)

[deniszykov]

@BinhNguyenPSA sorry I have no plans to expand this package. I gladly accept PR with new object serializer.