{"t":0,"type":"start"}
4
{
  "source": "sensor-1",
  "events": [
    {
      "t": 0,
      "type": "start"
    },
    {
      "t": 1,
      "type": "tick"
    },
    {
      "t": 2,
      "type": "tick"
    },
    {
      "t": 3,
      "type": "tick"
    }
  ]
}