JSON request:

{
    {
    "SetEaxMd": {
        "tEax": {
            "id": "Connection_Moniker!M!S!Dashboard_Moniker!DSO!Visualizer_Key"
        },
        "tArg": {
            "pattern": {
                "dataSources": "Set"
            },
            "meta": {
                "dataSources": {
                    "its": {
                        "it": [{
                            "k": 0,
                            "vis": true,
                            "cube": {
                                "obDesc": {
                                    "n": "",
                                    "i": "",
                                    "k": Visualizer_Source_Key,
                                    "c": Visualizer_Source_Key
                                }
                            }
                        }]
                    }
                }
            }
        }
    }
}

JSON response:

{
  "SetEaxMdResult":
   {
    "id":
     {
      "id": "Connection_Moniker!M!S!Dashboard_Moniker!DSO!Visualizer_Key"
     }
   }
}